CU-MCA-Mobile Applications Development Second draft-converted

MASTER OF COMPUTER APPLICATIONS SEMESTER V MOBILE APPLICATION DEVELOPMENT MCA652

CHANDIGARH UNIVERSITY Institute of Distance and Online Learning Course Development Committee Prof. (Dr.) R.S.Bawa Pro Chancellor, Chandigarh University, Gharuan, Punjab Advisors Prof. (Dr.) Bharat Bhushan, Director – IGNOU Prof. (Dr.) Majulika Srivastava, Director – CIQA, IGNOU Programme Coordinators & Editing Team Master of Business Administration (MBA) Bachelor of Business Administration (BBA) Coordinator – Dr. Rupali Arora Coordinator – Dr. Simran Jewandah Master of Computer Applications (MCA) Bachelor of Computer Applications (BCA) Coordinator – Dr. Raju Kumar Coordinator – Dr. Manisha Malhotra Master of Commerce (M.Com.) Bachelor of Commerce (B.Com.) Coordinator – Dr. Aman Jindal Coordinator – Dr. Minakshi Garg Master of Arts (Psychology) Bachelor of Science (Travel &Tourism Management) Coordinator – Dr. Samerjeet Kaur Coordinator – Dr. Shikha Sharma Master of Arts (English) Bachelor of Arts (General) Coordinator – Dr. Ashita Chadha Coordinator – Ms. Neeraj Gohlan Academic and Administrative Management Prof. (Dr.) R. M. Bhagat Prof. (Dr.) S.S. Sehgal Executive Director – Sciences Registrar Prof. (Dr.) Manaswini Acharya Prof. (Dr.) Gurpreet Singh Executive Director – Liberal Arts Director – IDOL © No part of this publication should be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording and/or otherwise without the prior written permission of the authors and the publisher. SLM SPECIALLY PREPARED FOR CU IDOL STUDENTS Printed and Published by: TeamLease Edtech Limited www.teamleaseedtech.com CONTACT NO:- 01133002345 For: CHANDIGARH UNIVERSITY 2 Institute of Distance and Online Learning CU IDOL SELF LEARNING MATERIAL (SLM)

First Published in 2021 All rights reserved. No Part of this book may be reproduced or transmitted, in any form or by any means, without permission in writing from Chandigarh University. Any person who does any unauthorized act in relation to this book may be liable to criminal prosecution and civil claims for damages. This book is meant for educational and learning purpose. The authors of the book has/have taken all reasonable care to ensure that the contents of the book do not violate any existing copyright or other intellectual property rights of any person in any manner whatsoever. In the event the Authors has/ have been unable to track any source and if any copyright has been inadvertently infringed, please notify the publisher in writing for corrective action. 3 CU IDOL SELF LEARNING MATERIAL (SLM)

CONTENTS Unit - 1: Android Basic Structure ..............................................................................................5 Unit - 2: Building Blocks.........................................................................................................21 Unit - 3: Fragments ..................................................................................................................36 Unit - 4: Ui-Widgets ................................................................................................................71 Unit - 5: Ui Controls ..............................................................................................................103 Unit – 6 : Layout Manager, Adaptor......................................................................................123 Unit - 7: Android Menu .........................................................................................................141 Unit - 8: Android Alarm,Drag And Drop Activity ................................................................167 Unit - 9: Multimedia ..............................................................................................................181 Unit - 10: Device Connectivity ..............................................................................................229 Unit - 11: Data Storage-1.......................................................................................................244 Unit - 12: Data Storage-2.......................................................................................................269 Unit - 13: Android Web-Services ..........................................................................................303 Unit - 14: Deployment ...........................................................................................................314 Unit - 15: Updating Existing Deployed Application .............................................................327 4 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT - 1: ANDROID BASIC STRUCTURE Structure 1.0 Learning Objectives 1.1 Introduction 1.2 Android Platform 1.3 Android Architecture 1.4 Android Stack 1.5 Dalvik Virtual Machine 1.6 Android vs. other mobile platforms 1.7 Summary 1.8 Keywords 1.9 Learning Activity 1.10 Unit End Questions 1.11 References 1.0 LEARNING OBJECTIVES After studying this unit, you will be able to: ● Define Android and its Functions ● Get knowledge about Android Architecture ● Describe working of Android Stack ● Differentiate between Android vs. other mobile platforms ● Describe how to Link Activity to the Intents 1.1 INTRODUCTION An Operating System (OS) manages pc resources, together with a pc's hardware (together with reminiscence and methods) and its software program. Android is a fast-transferring operating system primarily based totally at the Linux kernel, which includes about 12 million code linesKotlin is the brand new and secure programming; and while the Android studio became released, it have become the authentic programming.. Android makes use of a custom-designed digital machine to optimize reminiscence and hardware sources in a mobile 5 CU IDOL SELF LEARNING MATERIAL (SLM)

environment. Like Android OS, Google additionally backs up Chrome OS. Android OS is for embedded platforms, and Chrome OS is for Cloud-primarily based totally platforms. If you're using smartphones going for walks on Android, you is probably privy to the use of all of the programs. Some of the local Android programs are e mail consumer, SMS control application, a complete PIM (personal information management) suite, a Web Kit-primarily based totally internet browser, a tune player, and a photo gallery. The third-celebration programs are games, photo, and video-associated apps. Apart from the Android cell phones, the alternative embedded gadgets together with tablets, netbooks, television, set-pinnacle boxes, and vehicles have Android Operating System. The hardware varies on every Android device. These hardware variations help in writing device-unbiased code. The benefits of android are; it adopts quickly, can reuse it, it has a Free and open-supply SDK, and it helps operations to more than one platforms. The issues related to the Android Operating machine are - Fake Applications, problems withinside the history methods, and one version of OS crashing with the alternative OS. In 2003, a start-up organization named Android, Inc. advanced Android. In 2005, Google bought Android for improvement paintings and made it to be had as loose and open-supply software program. Later in 2007, a collection of enterprise human beings shaped an Open Handset Alliance to boost up cell innovation and offer a higher person enjoy. Google efficiently driven the Android platform to the leading edge in some years. But, ever surprise how the programs are advanced. In this chapter, we're looking to search out growing cell programs. Writing programs in Android calls for Java Framework, however now no longer Java. Another beneficial device for improvement is Extensible Markup language (XML) that's used to explain information sources. Android is a vacation spot for an extensive variety of beneficial libraries and equipment to construct wealthy programs. For the third- party software developers, Google assists in lots of forms as Android Development Tool (ADT) Plug-ins for Eclipse. 1.2 ANDROID PLATFORM What is Android? Android is an open-source, Linux-primarily based totally software program stack that consists of the operating system, middleware, and a software framework for constructing programs. Many hardware producers can now personalize Android due to no constant hardware or software program configurations for his or her extensive variety of products, like Game consoles, Digital cameras, Sensors, BT. Consequently, Android advanced past its creativeness and created a platform for software developers. We can say that Android is the maximum effective working machine withinside the marketplace. Storage, connectivity, internet browser, media, flash and hardware support, 6 CU IDOL SELF LEARNING MATERIAL (SLM)

multi-tasking, tethering, multi-contact, and messaging are Android capabilities. The following listing of capabilities are precise to Android, and won't be to be had on different cellular software platforms. They are Google maps programs, history services, programs, shared information and inter-procedure communication, Wi-Fi Direct, and Android Beam. Virtual Compatibility Compatability Machines Definition Test suite Document (CDD) Software Android Linux Development operating sysytem Kit (SDK) Kernel Opensource An Libraries Application framework An User Interface Framework Figure 1.1: Parts of Android Input information for Android customers the use of touch screens. Acoustic Resistive, Capacitive, and Surface Acoustic waves are plenty of display touch techniques. All Android gadgets use resistive or capacitive technology. The programming languages used to enhance Android programs are Java and Kotlin. Google loves Kotlin due to the fact it's far the authentic language of Android improvement. Android has a fixed of API libraries, and maximum third-celebration programs are written with the equal APIs, run simultaneously. These APIs encompass hardware access, video recording, location-primarily based totally services, background services, map-primarily based totally functions, associated facts, inter- system communications, Bluetooth, NFC, and 2D and 3Dimensions. Android Application Structure Android OS is constructed just like the following images. Images are saved in solid flash reminiscence and are protected while strength drops. Bootloader: Start loading the boot image for the primary time. BootImage: Kernel & RAM. Image System: Android working machine platform and apps. Image information: User information is saved in strength cycles. Image recovery: Files used to construct or update an application. 7 CU IDOL SELF LEARNING MATERIAL (SLM)

Radio image: Radio stack files. Overview of the Android app The Android application creates Tasks, Services, Content Providers, and Objectives. Functions are elements of building a user interface (UI). We know more about jobs in recent categories. Services are short-lived and may be closed at any time. Services run behind the scenes, and Tasks operate before the scenes. Content providers share data stored on a device used by many applications. Stream recipients display messages to the user in response to the action. Android versions Figure 1.2: Different Android Versions 1.3 ANDROID ARCHITECTURE Android Operating System architecture components support mobile device needs and are categorised into five sections in four main layers: Linux kernels, Libraries, Android Runtime, Application Framework, and Applications. ● Applications Applications form the upper layer in the Android architecture. The applications you write are included in this layer. It has pre-installed applications like home, contacts, camera, gallery, etc., 8 CU IDOL SELF LEARNING MATERIAL (SLM)

● Application Framework Application Framework provides several elementary classes that are used to create an Android application by the developers. It enables hardware access and directs the user interface with application sources. Which includes different services like the activity manager, notification manager, view system, package manager etc. ● Application runtime The components of the environment are, Dalvik virtual machine (DVM ) and core libraries. With the help of the core libraries, developers write Android Apps. DVM is a virtual machine that is specially adapted for Android. It assures that a device can efficiently run. ● Libraries The code segment of Android is present in this layer. It includes various C/C++ libraries, and Java-based libraries, such as Media, Graphics, Surface Manager, OpenGL, etc., ● Media library give support to play, record audio and video formats. ● The responsibility of a surface manager is to provide access to the display. ● SGL, OpenGL are cross-language, cross-platform application program interfaces (API) used for 2D and 3D graphics. ● SQLite provides database support, and Free-Type provides font support. ● Web-Kit is a web browser engine which provides all the functionality to display web content and simplify page loading. ● SSL is a technology which build an encrypted link between a web server and web browser. ● Linux Kernel Linux Kernel handles all the available drivers required for the runtime, such as display drivers, camera drivers, Bluetooth drivers, audio drivers and memory drivers etc. The Linux Kernel acts as a layer between the hardware devices and the other Android architecture components, which is responsible for memory, power, appliances, etc. 9 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.3: Android Architecture Source:https://www.geeksforgeeks.org/android-architecture/ 1.4 ANDROID STACK Android became created withinside the open-source kernel of Linux. One predominant purpose for selecting this kernel became that it supplied validated key capabilities for enhancing the Android app. The capabilities of the Linux kernel are: 1. Security: Linux kernel manages safety among machine and machine. Memory Management: 10 CU IDOL SELF LEARNING MATERIAL (SLM)

It manages reminiscence control for that reason giving us the liberty to enhance our apps. Process Management: Manages the process well, assign sources to methods every time they want them. 4.Net Stack Network: Manages network connectivity. 5.Driver Model: Make positive the app is running. Hardware manufacturers can construct their drivers in Linux build. Libraries: Running on the pinnacle of the kernel, the Android framework is constructed with plenty of materials. It has numerous C / C ++ libraries with many open-source equipment as: 1. Android operating time: The android operating time incorporates the primary Java and ART libraries (Android Runtime). Older variations had Dalvik operating time. 2. Open GL (portraits library): This interface-language, cross-platform software application interface (API) is used to supply 2D and 3-D laptop graphics. 3. Web Kit: This open-supply browser engine gives all of the capability to show internet content material and simplify web page loading. Newsgroups: These libraries let you play and report audio and video. 5.Locket Socket Layer (SSL): These libraries are to be had for Internet safety. 1.5 DALVIK VIRTUAL MACHINE | DVM As we probable are conscious the superior JVM is advanced and offers terrific reminiscence to the executives. Be that because it may, it must be advanced for low-fuelled hand held devices additionally. The Dalvik Virtual Machine (DVM) is an android digital gadget advanced for mobileular phones. It enhancements the digital gadget for reminiscence, battery life, and execution. 11 CU IDOL SELF LEARNING MATERIAL (SLM)

Dalvik is a name of a city in Iceland. The Dalvik VM became composed via way of means of Dan Bornstein. The Dex compiler modifications over the elegance facts into the .dex record that unexpected spike in call for the Dalvik VM. Various elegance files are modified over into one dex record. We must see the incorporating and bundling degree from the source record: Let's see the compiling and packaging procedure from the source file: Figure 1.4. compiling and packaging process from the source file The javac device aggregates the java source record into the elegance report. The dx device takes all of the elegance files of your software and creates a solitary .dex report. It is a degree specific apparatus. The Android Assets Packaging Tool (aapt) handles the bundling cycle. 1.6 ANDROID VS. OTHER MOBILE PLATFORMS An superior mobileular developer can choose exclusive levels likewise but growing for Android is a part less complicated and commendable. As a designer, all people can create programs for the Android marketplace. Point is: • No confirmation is required. 12 CU IDOL SELF LEARNING MATERIAL (SLM)

• Software Development Kit (SDK) is liberated from fee and is savvy sufficient to refresh itself with few ticks. • Development weather may be Windows, Linux, or Mac OS. • Android marketplace is there for move of your programs. • No outsider endorsement is wanted for the appropriation of programs withinside the marketplace. • You want a functioning internet affiliation and preference to realise, this is it!!! • Start gaining from any location and any location, would not make any difference. Some different transportable SDK can likewise be applied for getting to know and procuring, for what purpose to choose android? Here is a part of the first rate highlights which make android critically enticing and that they are: • The programs downloaded from the marketplace and those with which the system became transported are given equal significance. • Windows may be made into your programs out of your very own telecellsmartphone's domestic display via way of means of using stay backdrops, devices, and so on • It reacts while the restrict event occurs like while a pre-determined place indicates up, the system advises the client. • Google Maps is the best hit on this situation. • Open-source degree with thousands of checks which makes expectancies soak up facts little. How approximately we find out now no longer many contrasts amongst Android and different prestigious levels, in particular, iOS, Blackberry, and Windows. ANDROID VERSUS IOS Both Android and iOS are riding elements withinside the marketplace of mobileular phones. How approximately we pen down multiple contrasts among them. • Android is the maximum extensively applied mobileular phone degree on earth and it's far used by numerous system manufacturers like LG, Samsung, HTC, and so on iOS is applied noticeably on Apple devices like iPad, iTouch, Apple TV, and so on 13 CU IDOL SELF LEARNING MATERIAL (SLM)

• Android allows the usage of devices, which display the programmed refreshed information. iOS has a column of programs on the home display. • Varieties of Android devices are available with contrasting sizes and device capacities. The consumer can choose any of them as indicated via way of means of his/her necessity and monetary plan. iOS is obtainable simply on Apple devices and they'll in wellknown be costly. • Users can go to non-android devices via GTalk. iOS would not provide the nearby speak software to non-apple clients. • Google chrome is obtainable on Android devices. They may be integrated with IOS devices. iOS has Safari as a web browser which is not available for an Android system. • Android allows far off instalments with Near subject correspondence, that's attainable via way of means of Google wallet. iOS offers a Passbook software, which messes approximately charge/card cards, but would not allow far off transportable instalments. • Android programs may be changed in C, C++, and JAVA. Anybody can down load SDK and start generating for nothing. Clients can down load a big wide variety of programs freed from charge. • Android SDK is obtainable for all levels: PC, Mac, and Linux. It is an open and loose degree. iOS SDK is obtainable for Mac because it were. It is a close degree. • Android system's battery can surely be supplanted. IOS battery cannot be supplanted, henceforth one wishes to maintain the charger organized for the module. • Android has the second one largest software shop. Applications want everyday updates which once more contrasts amongst numerous sorts of Android. iOS has the most important software shop. The equal replace is wanted for all devices. As android is tied up with Google's modern situation it's far the primary impetus in the back of maximum sizeable people converting from iPhone to Android. ANDROID VERSUS BLACKBERRY 14 CU IDOL SELF LEARNING MATERIAL (SLM)

Both android and blackberry are extreme contenders however they serve severa prerequisites. We must pen down fine variations • a complete touch show display enjoy may be delighted with android. Special system makers set their very own interface at the top of the important android layer for example Samsung has its TouchWiz, Motorola has moto blur, and so on Most blackberries do not have a hint interface apart from hurricane and torch at the same time as this article have become composed. • in the instance of customization of the residence show display, android is a victor in the marketplace. It allows severa domestic displays. Blackberry is horrible in customization. • android is a hint-primarily based totally framework and henceforth path is treated via way of means of the use of shopping for and selling, tapping, and squeezing. They likewise have a home show, again key, and so on, which shifts from one maker to another. Blackberry offers a tune cushion to the direction. More seasoned blackberries had trackball for the direction. • android is a dedicated a part of in-activity programs and exclusive cool to-do-matters programs. But Gmail, most messages want to be checked intermittently. Blackberry is devoted to a sturdy correspondence agency. At anything factor an e-mail drops withinside the inbox, the consumer is knowledgeable. • android's market is first-rate while contrasted with the blackberry save. • android programs require common updates. Blackberry is consistent. • android is an open-deliver degree so it very well may be changed or hacked with none hassle. This is the reason regular updates are introduced simply so bugs can be consistent. Blackberry uses its on worker and therefore, it's miles substantially gotten. But, on the off hazard that employee comes up short, the issue is inescapable and it might require days to healing the mistake. Blackberries are usually affordable for individuals who are insured groups and need consistent correspondence. Android offers a big patron enjoy. 15 CU IDOL SELF LEARNING MATERIAL (SLM)

Android as opposed to domestic home windows Windows have an company with Nokia. As we as a whole realise now Nokia is enabled with the useful resource of Microsoft and it surpassed the Symbian os and placed itself in the market. We have to pen down precise focuses about the two of them. • an android gadget makes use of an android working system and it's far open-deliver. Domestic home windows mobile phone uses domestic home windows strolling framework that could be an aggregate of the open and close framework. • android clients are allowed to choose any software program from the market and engineers do now no longer understand a selected affiliation the save you consumer's pinnacle fees. Say, a google map may be utilized by an understudy or a rancher to apprehend his/her vicinity. Home domestic home windows aim programs in moderate of give up patron. • android machine boots itself inner more than one moments. Home home windows telephone want to be truly booted in seconds, anyways, the set spec will now no longer be met. • sd card of an android device is replaceable. The sd card can't be supplanted. With SkyDrive, you may have allotted storage. • android applications can be a part of themselves and provide information or enables amongst degree correspondence. Window's phone permits every software to open in a sandbox so one-of-a-type quantities of the running framework are left undisturbed. • android's applications shop is noticeably widespread. They have were given the littlest but fastest developing applications to maintain. Home windows phone may be carried out if protection is the number one problem and android can be implemented on the off danger which you simply want your telephone to act savvy enough like a telephone must do. 16 CU IDOL SELF LEARNING MATERIAL (SLM)

1.7 SUMMARY • Android engineering is a product pile of parts to assist cellular telephone needs. Android programming stack carries a Linux kernel, a collection of c/c++ libraries that are exposed thru an application structure administrations, runtime, and application. Following are the most important components of android engineering the ones are a. Programs b. Android framework c. Android runtime d. Platform libraries e. Linux kernel • In those segments, the Linux kernel is the primary part in android to offer its running framework capacities to portable and Dalvik virtual device (DVM) which is answerable for walking a flexible application. • A respectable android advancement information status quo requires a comprehension of the general engineering of android. Android is finished as a product stack engineering comprising of a Linux bit, a runtime climate and evaluating libraries, a utility machine, and a bunch of uses. Packages are overwhelmingly written in java or kotlin and arranged down to bytecode layout inside the android studio fabricate weather. At the point when the application is as a result delivered on a gadget, this bytecode is organized somewhere close to the android runtime (art) to the nearby configuration utilized by the CPU. • The vital objectives of android engineering are execution and effectiveness, both in utility execution and inside the execution of reuse in the application plan. 1.8 KEYWORDS • Media library- give support to play, record audio and video formats. • Surface manager- The responsibility of a surface manager is to provide access to the display. • SQLite- SQLite provides database support, and Free-Type provides font support. • Web-Kit- is a web browser engine which provides all the functionality to display web content and simplify page loading. • SSL- SSL is a technology which build an encrypted link between a web server and web browser. 17 CU IDOL SELF LEARNING MATERIAL (SLM)

1.9 LEARNING ACTIVITY 1. Draw a comparative chart for different types of Operating System with features. ___________________________________________________________________________ ___________________________________________________________________ 2. Compare Dalvik Virtual Machine | DVM. ___________________________________________________________________________ _____________________________________________________________ 1.10 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. What is android? 2. What is the Android SDK? 3. What are the distinct variations of android os which you bear in mind? 4. Call the languages supported for android development. 5. What are the blessings of the android working device? Long Questions 1. Explain in detail Android Architecture? 2.What are the different tools available in Android development? Explain them. 3. What is Android runtime? 4. What are the advantages and disadvantages of Android? 5. How Android different from IOS? B. Multiple Choice Questions 1. Which section provides a key component called Dalvik Virtual Machine? a. Libraries b. Android Runtime c. Application Framework d. Applications 18 CU IDOL SELF LEARNING MATERIAL (SLM)

2. Which of the following libraries provides access to the application model and is the cornerstone of all Android applications? a. android.app b. android.content c. android.database d. android.widget 3. Top Layer is known as? a. Libraries b. Android Runtime c. Application Framework d. Applications 4. Bottom layer is known as? a. Libraries b. Linux kernel c. Application Framework d. Applications 5. Android operating system is a stack of software components which is roughly divided into how many layers? a. 2 b. 3 c. 4 d. 5 Answers 1-b, 2-a, 3-d, 4-d, 5-c 1.11 REFERENCES Reference Books 19 CU IDOL SELF LEARNING MATERIAL (SLM)

• Khoshafian, et al. (1990). Object orientation: Concepts, Languages, Databases. New York: John Wiley & Sons • Thornsby, J. (May 2016). Android UI Design. Packt Publishing. Morris, J. (Feb 2011). Android User Interface Development - Beginner’s Guide. UK. Packt Publishing Websites • https://enos.itcollege.ee/~jpoial/allalaadimised/reading/Android-UI-Design.pdf • https://www.techotopia.com/index.php/Understanding_Android_Views,_View_Group s_and_Layouts • https://www.tutorialspoint.com/software_architecture_design/user_interface.htm • https://www.wideskills.com/android/building-user-interface/listening-to-ui- notifications-in-android • https://developer.android.com/guide/fragments/lifecycle 20 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT - 2: BUILDING BLOCKS 21 Structure 2.0 Learning Objectives 2.1 Introduction 2.2 Activities 2.2.1 Activity Life Cycle 2.3 Services 2.3.1 Services Life Cycle 2.4 Content Providers 2.5 Broadcast Receiver 2.6 Intents 2.7 Summary 2.8 Keywords 2.9 Learning Activity 2.10 Unit End Questions 2.11 References 2.0 LEARNING OBJECTIVES After studying this unit, you will be able to: ● Learn building blocks in android ● Implement activities and its life cycle ● Describe about services and its life cycle ● Explain Content Providers ● Evaluate Broadcast Receiver ● Implement Intents CU IDOL SELF LEARNING MATERIAL (SLM)

2.1 INTRODUCTION Building blocks or application components of an Android application defines the behaviour of the application. Each Android application has four types of components; each component plays a specific role and has its own lifecycle. They are described below. 2.2 ACTIVITY Interest is a UI provided as a show display with which a patron communicates. For example, assuming you open a media participant utility, the display that helps you to play, stop, next, or past the track is an interest. An interest can each be geared up into the entire display or can skim over unique screens. An android software should have precise sports associated with every different. The absolute first interest that renders at the display withinside the wake of starting the software is known as the default interest. Movement is commonly a solitary display that the customer sees at the device at one time. Software generally has various Activities, and the patron flips backward and forward among them. Consequently, wearing sports are the maximum apparent piece of your utility. Very much like a website comprises numerous pages, so does android software program include severa Activities. Truly, like a website has a \"touchdown web page,\" an android utility has an \"essential” movement, generally, the simplest that is proven first whilst you dispatch the software program. What's more, very similar to a website wants to provide a form of course amongst particular pages, an android software wishes to do likewise. On the net, you may hop from an internet page on one internet site on-line to a web page on a few different. Additionally, in android, you could be taking a gander on the motion of one software program, but now no longer lengthy after you could begin any other movement in a completely remoted software. For instance, withinside the occasion in that you are to your contacts utility and making a decision to message an accomplice, you may dispatch the movement to form an immediately message withinside the messaging software. 2.2.1 Activity Life Cycle Dispatching a movement can be very luxurious. It'd embody making any other Linux interaction, designating memory for all the UI devices, increasing each one of the devices from XML formats, and putting in the entire display. Considering the truth that we're doing a ton of hard work to dispatch an motion, it would be a loss to truly throw it out as quickly because the consumer leaves that show. To stay farfar from this waste, the energetic life-style cycle is overseen with the resource of the interest supervisor. The motion supervisor is responsible for making, obliterating, and overseeing Activities. As an instance, whilst the patron starts off evolved a software program curiously, the hobby supervisor will make its activities and located them onto the show. Later on, whilst the 22 CU IDOL SELF LEARNING MATERIAL (SLM)

customer switches monitors, the hobby manager will glide that beyond movement to a retaining vicinity. Thusly, if the patron wishes to go back to an extra seasoned movement, it has a bent to start all of the greater rapidly. More hooked up wearing activities that the patron hasn't applied in some time may be obliterated to free extra place for the at present dynamic one. This tool is supposed to help enhance the velocity of the UI and therefore beautify the overall client revel in. Programming for Android is reasonably not quite similar to programming for some extraordinary situations. In android, you emerge as reacting greater to specific changes withinside the situation of your software program rather than using that alternate yourself. It's miles an overseen, holder-based weather-like programming for java applets or servlets. In this manner, as regards to an active life cycle, you do not will say what express the movement is in, but you've got were given a whole lot of freedoms to mention what takes area throughout the adjustments from one us of a toother. Figure 2.1 suggests the states that motion can pass thru. Figure 2.1 shows the states that action can go through. Figure 2-1. Activity life cycle Starting state When an асtivity doesn’t exist in memory, it's miles in а beginning country. While it’s starting up, the асtivity will move via а entire set of саll bасk techniques that you as а develорer have an орроrtunity tо fill оut. Eventuаlly, the асtivity will be in а running stаte. 23 CU IDOL SELF LEARNING MATERIAL (SLM)

Preserve in mind that this transition from stаrting country tо going for walks stаte is оne оf the mоst expensive орerаtiоns in terms оf соmрuting time, and this additionally at once аffeсts the bаttery life оf the tool. This is the exасt reаsоn why we dоn’t аutоmаtiсаlly destrоy асtivities thаt аre nо lоnger shоwn. The consumer might wаnt tо соme bасokay tо them, sо we keeр them аrоund fоr а even as.. Running stаte The асtivity in а Running stаte is the оne thаt is сurrently оn the sсreen аnd interасting with the person. We аlsо sаy this асtivity is in fосus, meаning thаt аll user interасtiоns—suсh аs tyрing, tоuсhing the sсreen, аnd сliсking buttоns—аre hаndled through this оne асtivity. аs suсh, there is оnly оne going for walks асtivity аt аbig apple given time. The running асtivity is the оne thаt hаs рriоrity in phrases оf getting the memоry аnd resоurсes it wishes tо run аs quiсkly аs роssible. This is beсаuse аndrоid wаnts tо mаke sure the walking асtivity is ziррy аnd resроnsive tо the consumer раused stаte When аn асtivity is nоt in fосus (i.E., nоt interасting with the person) but nonetheless visible оn the sсreen, we sаy it’s in а раused stаte. This is nоt а tyрiсаl sсenаriо, beсаuse the deviсe’s sсreen is usuаlly smаll, аnd аn асtivity is either tаking uр the whоle sсreen оr nоne аt аll. We оften see this саse with diаlоg bоxes thаt соme uр in frоnt оf аn асtivity, саusing it tо beсоme раused. аll асtivities gо thrоugh а раused stаte rоute tо being stоррed. раused асtivities nevertheless hаve excessive рriоrity in phrases оf getting memоry аnd оther resоurсes. This is beсаuse they аre visible аnd саnnоt be remоved frоm the sсreen withоut mаking it lооokay very strаnge tо the person. Stоррed stаte Whilst аn асtivity is nоt seen, but nonetheless in memоry, we sаy it’s in а stоррed stаte. Stоррed асtivity соuld be brоught bасk tо the frоnt tо beсоme а walking асtivity аgаin. оr, it соuld be destrоyed аnd remоved frоm memоry. The tool keeрs асtivities аrоund in а stоррed stаte beсаuse it is probable thаt the consumer will nevertheless wаnt tо get bасokay tо thоse асtivities sоme time sооn, аnd relaxationаrting а stоррed асtivity is fаr сheарer thаn stаrting аn асtivity frоm sсrаtсh. Thаt is beсаuse we аlreаdy hаve аll the оbjeсts lоаded in memоry аnd simрly hаve tо convey it аll uр tо the fоregrоund. Stоррed асtivities саn be remоved frоm memоry аt аny роint.. Destrоyed stаte 24 CU IDOL SELF LEARNING MATERIAL (SLM)

а destrоyed асtivity is nо lоnger in memоry. The асtivity mаnаger deсided thаt this асtivity is nо lоnger wished аnd hаs remоved it. Befоre the асtivity is destrоyed, it саn рerfоrm сertаin асtiоns, suсh аs sаve аthe huge apple unsаved infоrmаtiоn. Hоwever, there’s nо guаrаntee thаt yоur асtivity will be stоррed рriоr tо being destrоyed. It is роssible fоr а раused асtivity tо be destrоyed аs properly. Fоr thаt reаsоn, it is higher tо dо imроrtаnt wоrk, suсh аs sаving unsаved dаtа, stop rоute tо а раused stаte rаther thаn а destrоyed stаte. 2.3 SERVICES A Servive service is a software component that runs withinside the records and does now no longer want any patron interface. For instance, in case you are using a web browser and determine to down load a record, then the report might be downloaded withinside the history whilst you maintain your interplay with the net browser. This is being achieved because of an utility problem known as a service. An activity can begin a service. You can also bind an issuer to an interest to have interaction with it. 2.3.1. Service life cycle Also, the Service life cycle is greater or much less controlled through manner of the developer, and not loads thru the machine. Therefore, we as developers want to apprehend to run our services just so they don’t consume shared reasserts unnecessarily, which incorporates the CPU and battery. Figure 2.2. Service life cycle 2.4CONTENT PROVIDERS A content provider is a component that manages the utility information saved in an SQLite database, document system, on the net, or every other garage place accessed by your utility. Using the content provider different programs can get entry to or regulate the statistics of your utility. For instance, the android gadget can offer contact data to the messaging app through the content material issuer. It's also useful in handling and querying the non-public statistics of the app. 25 CU IDOL SELF LEARNING MATERIAL (SLM)

Although small quantities of records can be handed between programs through intents, content material providers are a whole lot better suitable for sharing continual information between probably massive datasets. As such, the content company API nicely adheres to the crud precept. The parent underneath illustrates how the content company’s crud interface pierces the application barriers and lets in other apps to connect to it to proportion data.. Figure 2.3 Content provider The android device uses this mechanism all the time. As an instance, a contacts company is a content material issuer that exposes all user touch facts to diverse applications. Settings company exposes device settings to diverse programs, which consist of the integrated settings software. Media hold is responsible for storing and sharing various media, inclusive of pictures and track, throughout diverse packages. The figure under illustrates how the contacts app uses contacts issuer, a completely separate software program, to retrieve data approximately users’ contacts. The contacts app itself doesn’t have any touch data, and the contacts company doesn’t have any patron interface. 26 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.4 Contacts application using Contacts Provider to get the data This separation of data garage and the real user interface software offers greater flexibility to mash up various parts of the gadget. As an example, a user could install an alternative address book software that uses equal records as the default contacts app. Or, he should set up widgets on the house display screen that permit for clean changes within the machine settings, along with turning on or off the Wifi, Bluetooth, or GPS features. Many telephone manufacturers take gain of content material carriers to feature their personal packages on top of trendy android to improve basic user revel in, which includes the experience. Content providers are pretty simple interfaces, with the standard insert(), replace(), delete(), and query() strategies. These methods look loads like general database methods, so it is pretty easy to put in force a content company as a proxy to the database. Having stated that, you are much more likely to use content material carriers than write your very own. 2.5BROADCAST RECEIVERS A published receiver is used to broadcast the bulletins to the complete device whether or not it's miles a notification to the popularity bar to alert the consumer or it's far a message to some other utility or interest. As an instance, in case you either get hold of a notification on the repute bar approximately final touch of down load or receiving a textual content message approximately the new replacement of the app, it happens due to the printed receivers. Even, a broadcast receiver can begin a carrier at the incidence of a predefined event. The machine itself publicizes occasions all the time. For instance, while an SMS arrives, a name is available in, the battery runs low, or the system gets booted, all the occasions are broadcasted, and any quantity of receivers might be prompted by means of them. 27 CU IDOL SELF LEARNING MATERIAL (SLM)

In our Twitter app instance, we need to start the replace carrier as soon as the gadget starts off evolved up. To do this, we are able to join the publication that tells us the gadget has finished booting up. You could additionally send your personal publicizes from one part of your application to another, or to a very exclusive application. Broadcast receivers themselves do not have any visible representation, nor are they actively jogging in memory. However, when triggered, they get to execute some code, along with starting an interest, a service, or something else. 2.6 INTENTS Intents are messages which is probably sent most of the important constructing blocks. They cause hobby to start up, tell an issuer to start or prevent, or are definitely proclaims. Intents are asynchronous, that means the code that sends them doesn’t have to look forward to them to be completed. Cause perhaps express or implicit. For a selected purpose, the sender sincerely spells out which precise problem have to be at the receiving quit. In an implicit intent, the sender specifies the kind of receiver. For instance, your interest should ship a reason pronouncing it truely desires someone to open up a web web page. If so, any utility that is able to setting out a web net web page should “compete” to complete this motion. If you've got competing packages, the device will ask you which of them ones you’d like to apply to finish a given movement. You can moreover set an app due to the default. This mechanism works very in addition for your laptop surroundings, for example, whilst you downloaded firefox or chrome to replace your default internet explorer or safari internet browsers. This form of messaging permits the patron to replace any app at the device with a custom one. For instance, you would possibly want to down load tremendous SMS software program or any other browser to update your modern-day ones. 28 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.5. Intents 2.7 SUMMARY App components are the important building blocks of an android app. Everything is a get entry to factor through which the tool or someone can enter your app. Some components rely upon others. There are 4 particular kinds of app components: • Activities • services • broadcast receivers • content material carriers Every kind serves an exceptional cause and has an exceptional lifecycle that defines how the thing is created and destroyedApp components are the important constructing blocks of an Android app. Each issue is an access factor thru which the gadget or a consumer can input your app. Some components rely on others. Activities An activity is the access thing for interacting with the user. It represents a unmarried show with a private interface. For example, an e-mail app would possibly have one interest that suggests a listing of new emails, each different interest to compose an e mail, and any other hobby for studying emails. Despite the truth that the sports activities work together to shape a cohesive client enjoy withinside the e mail app, anybody is unbiased of the others. As such, a one-of-a-type app can begin any character of those sports if the email app lets in it. As an example, a virtual digital digicam app can begin the interest in the e-mail app that composes new mail to allow the character to share a photograph. An interest allows the subsequent key interactions among gadget and app: • preserving in track with what the client currently cares approximately (what's on-show display) to make certain that the tool maintains strolling the process this is web website hosting the hobby. • understanding that formerly used techniques contain matters the consumer may also moreover move lower back to (stopped sports activities), and consequently greater particularly prioritize maintaining the ones procedures round. • assisting the app cope with having its method killed so the consumer can move lower back to sports with their previous country restored. 29 CU IDOL SELF LEARNING MATERIAL (SLM)

• providing a manner for apps to enforce consumer flows amongst each different, and for the tool to coordinate those flows. (the maximum conventional example proper right here being a share.) You put into effect an activity as a subclass of the Activity class Services A service is a desired purpose access factor for maintaining an app jogging withinside the historic beyond for all forms of motives. It is a part that runs in records to perform lengthy- running operations or to perform paintings for a long way-off processes. A carrier does no longer provide a private interface. As an example, a service might probable play song in the historic beyond even as the client is in a one-of-a-type app, or it would fetch data over the network without blockading user interaction with an interest. Another thing, including an hobby, can start the service and permit it to run or bind to it as a way to engage with it. There are absolutely very first rate semantics services that tell the gadget approximately a manner to control an app: began out offerings inform the gadget to hold them taking walks till their art work are completed. This can be to sync some portions of facts withinside the historic beyond or play a tune even after the person leaves the app. Syncing information withinside the historic beyond or playing tune additionally represent wonderful forms of started out offerings that alter how the tool handles them: • track playback is something the client is at once privy to, so the app tells the gadget this via way of means of pronouncing it desires to be foreground with a notification to tell the person about it; on this case, the tool is privy to that it has to strive in reality hard to preserve that carrier's way running because of the truth the client may be unhappy if it's miles going away. • an normal background carrier is not something the consumer is at once privy to running, so the gadget has greater freedom in managing its way. It can allow it to be killed (after which restarting the carrier someday later) Bound services run due to the fact some different apps (or the gadget) has stated that it desires to rent the service. This is basically the service providing an API in any other way. The gadget because of this is aware of there may be a dependency amongst those techniques, so if method a is positive to carrier in gadget b, its miles conscious that it wants to keep method b (and its carrier) strolling for a. Similarly, if the gadget a is something the character cares approximately, and then it additionally is aware of to deal with way b as something the person moreover cares about. Because in their flexibility (for better or worse), offerings have turn out to be out to be an in fact beneficial constructing block for all varieties of better- diploma gadget principles. Stay wallpapers, notification listeners, show savers, input methods, accessibility services, and lots of different centre gadget functions are all constructed as services that programs put into effect and the tool binds to when they should be running. 30 CU IDOL SELF LEARNING MATERIAL (SLM)

Broadcast receivers A broadcast receiver is part that lets in the device to deliver activities to the app out of the doorways of an ordinary character go together with the flow, permitting the app to answer to device-huge broadcast announcements. Due to the truth broadcast receivers are each different properly described get entry to into the app, the gadget can deliver pronounces even to apps that are not currently strolling. So, for example, an app can time desk an alarm to publish a notification to tell the consumer about an upcoming event... And via way of means of manner of turning in that alarm to a posted receiver of the app, there may be no want for the app to stay strolling till the alarm is going off. Many publicize originate from the device—as for example, a published saying that the show display has become off, the battery is low, or an image become capture. Apps also can provoke broadcasts—for example, to allow unique apps to apprehend that some data were downloaded to the tool and are available for them to use. Despite the truth that broadcast receivers do not show someone interface, they will create a standing bar notification to alert the character at the same time as a broadcast occasion takes location. Greater typically, although, a published receiver is handiest a gateway to different components and is supposed to do a completely minimal amount of labour. For example, it might schedule a method carrier to carry out some works based totally at the event with the mission scheduler A broadcast receiver is carried out as a subclass of the printed receiver and each broadcast is added as a purpose object. For greater data, see the broadcast receiver class. Content providers A content provider manages a shared set of app information that you could store in the record device, in an SQLite database, at the web, or on a few different continual storage location that your app can get entry to. Thru the content material material company, unique apps can query or regulate the records if the content material corporation allows it. For example, the android tool offers a content material issuer that manages the client's contact facts. As such, any app with the right permissions can query the content provider, which incorporates contacts settlement. Statistics, to take a look at and write data about a particular guy or woman. It's a long way tempting to consider a content material company as an abstraction on a database due to the fact there is lots of API and useful resource built into them for that common purpose. However, they've got a completely unique middle purpose from a gadget-format attitude. To the tool, a content material issuer is an access thing into an app for publishing named data gadgets, identified with the useful resource of a URI scheme. As a consequence, an app can determine the way it desires to map the facts it carries to a URI namespace, handing out those URI to unique entities which can, in turn, use them to get admission to the data. There are a few unique matters this lets in the gadget to do in handling an app: • assigning a URI might now no longer require that the app live taking walks, so URI can persist after their proudly owning apps have exited. The tool best needs to make certain that 31 CU IDOL SELF LEARNING MATERIAL (SLM)

an owning app is still taking walks at the same time as it has to retrieve the app's records from the corresponding URI. • those URI moreover offer an crucial satisfactory-grained protection model. As an example, an app can location the URI for an image it has at the clipboard however is going away with its content material provider locked up in order that different apps can't freely get admission to it. While a second app attempts to get admission to that URI on the clipboard, the gadget can allow that app to get proper of access to the facts via a short URI permission deliver in order that it's miles allowed to get entry to the data handiest in the back of that URI, but not anything else withinside the second app. Content vendors are useful for studying and writing facts this is private to your app and no longer shared. 2.8 KEYWORDS • Activity-An activity is a class that represents a single screen • View-A view is the UI element such as button, label, text field etc. Anything that you see is a view • Intent-Intent is used to invoke components • Service-Service is a background process that can run for a long time. • Content Provider-Content Providers are used to share data between the applications 2.9LEARNING ACTIVITY 1. Create an activity life cycle that displaces a proper message in log cat. ___________________________________________________________________________ _____________________________________________________________ 2. Why do you manage the logic component and the design component one by one? Which kind of files incorporates the common-sense element and design component? ___________________________________________________________________________ _____________________________________________________________ 3. What's an. Apk report? What are the ingredients of it? How is it created? Provide an explanation for. ___________________________________________________________________________ _____________________________________________________________ 4. Discover and explain the contents of the “res” folder. ___________________________________________________________________________ ___________________________________________________________ 32 CU IDOL SELF LEARNING MATERIAL (SLM)

2.10 UNIT END QUESTIONS 33 A. Descriptive Questions Short Questions 1. What is Activity? 2. What is Broadcast receiver? 3. What are Intents? 4. What are the Services? 5. What are the Content Provider? Long Questions 1. What is the core building blocks of Android? 2. What is an Activity in Android? What is its lifecycle? 3. Whatare the need of AndroidManifest.xml in Android? 4. What are a Services in Android? What is its lifecycle? 5. What are Intents? Explain them? B. Multiple Choice Questions 1. What is Pending Intent in android? a. It is a kind of an intent b. It is used to pass the data between activities c. It will fire at a future point of time. d. None of these 2. What are the layouts available in android? a. Linear Layout b. Frame Layout c. Table Layout d. Relative Layout e. All of these 3. How to stop the services in android? a. finish() CU IDOL SELF LEARNING MATERIAL (SLM)

b. system.exit(). c. By manually d. stopSelf() and stopService() 4. How many applications are there in a given task in android? a. Two b. One c. Many d. Zero 5. What are the wake locks available in android? a. PARTIAL_WAKE_LOCK b. SCREEN_DIM_WAKE_LOCK c. SCREEN_BRIGHT_WAKE_LOCK d. FULL_WAKE_LOCK e. FULL_WAKE_LOCK Answers: 1-c, 2-e, 3-d, 4-c, 5-e 2.11 REFERENCES Reference Books • Khoshafian, et al. (1990). Object orientation: Concepts, Languages, Databases. New York: John Wiley & Sons • Thornsby, J. (May 2016). Android UI Design. Packt Publishing. Morris, J. (Feb 2011). Android User Interface Development - Beginner’s Guide. UK. Packt Publishing Websites • https://enos.itcollege.ee/~jpoial/allalaadimised/reading/Android-UI-Design.pdf • https://www.techotopia.com/index.php/Understanding_Android_Views,_View_Group s_and_Layouts • https://www.tutorialspoint.com/software_architecture_design/user_interface.htm 34 CU IDOL SELF LEARNING MATERIAL (SLM)

• https://www.wideskills.com/android/building-user-interface/listening-to-ui- notifications-in-android • https://developer.android.com/guide/fragments/lifecycle 35 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT - 3: FRAGMENTS Structure 3.0 Learning Objectives 3.1 Introduction 3.2 Types of fragments 3.3 Fragment Life Cycle 3.4 Summary 3.5 Keywords 3.6 Learning Activity 3.7 Unit End Questions 3.8 References 3.0 LEARNING OBJECTIVES After studying this unit, you will be able to: • Implement Fragments • Describe the types of fragments • Understand Fragment Life Cycle • Brief working with fragments • Know importance of fragments 3.1 INTRODUCTION Fragment components encapsulate an individual segment of the user interface. They may be crucial whilst the developer has to build or optimize a software person interface for multiple display sizes or devices A fragment is a reusable magnificence imposing a part of an activity. A fraction generally defines part of a user interface. Fragments ought to be embedded in activities; they cannot run independently of activities. 36 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 3.1. Fragment’s activities Understanding Fragments Here are the crucial matters to apprehend approximately fragments: • a fragment is a mixture of an XML format report and a java class similar to a hobby. • using the assist library, fragments are supported returned to all applicable android variations. • fragments encapsulate perspectives and good judgment in order that its miles less difficult to reuse within activities. • fragments are standalone additives that can contain perspectives, occasions, and logic. • Inside a fragment-oriented structure, sports become navigational containers which are typically accountable for navigation to different activities, imparting fragments, and passing records. Importance of Fragments There are numerous use cases for fragments but the most not unusual use instances include: • reusing view and good judgment components - fragments allow re-use of components of your display screen along with perspectives and event good judgment again and again in exceptional approaches throughout many disparate activities. For instance, the use of the identical listing throughout distinctive facts sources inside an app. 37 CU IDOL SELF LEARNING MATERIAL (SLM)

• tablet support - regularly inside apps, the pill model of activity has an extensively different layout from the cellphone version which is different from the television version. Fragments enable tool-unique activities to reuse shared factors whilst also having variations. • display screen orientation - frequently inside apps, the portrait model of activity has a notable one-of-a-kind layout from the landscape model. Fragments permit both orientations to reuse shared factors whilst additionally having differences. Organizing your Code Inside a fraction-heavy app, we need to recall to arrange our code according to architectural pleasant practices. Interior of an app that makes use of fragments significantly, we need to keep in mind that the position of pastime shifts. Activities are navigation controllers broadly speaking responsible for: • navigation to different activities via intents. • supplying navigational components which include the navigation drawer or the view pager. • hiding and displaying relevant fragments the use of the fragment supervisor. • receiving records from intents and passing records between fragments. • Fragments are content controllers and include maximum perspectives, layouts, and occasion good judgment such as: • layouts and perspectives displaying relevant app content. • occasion coping with good judgment related to relevant views. • view state control common sense such as visibility or mistakes coping with. • triggering of network requests thru a purchaser object. • retrieval and storage of information from patience thru model gadgets. To reiterate, in a fragment-primarily based structure, the sports are for navigation and the fragments are for perspectives and common sense. Usage Defining a Fragment A fragment, like an activity, has an XML report and a java class that represents the fragment controller. The xml document is much like another report, and can be named fragment_oof.Xml. Consider them as a partial (re-usable) activity: <?Xmlns version= \" 1.0 \" encoding= \" utf-8 \"?> <LinearLayout xmlns: android= \" http://schemas.Android.Com/apk/res/android\" Android: layout_width=\"match_parent\" android: layout_height=\"match_parent\" 38 CU IDOL SELF LEARNING MATERIAL (SLM)

Android: orientation=\"vertical\" > <TextView Android:id=\"@+id/textView1\" Android: layout_width=\"wrap_content\" Android: layout_height=\"wrap_content\" Android: text=\"TextView\" /> <Button Android:id=\"@+id/button1\" Android: layout_width=\"wrap_content\" Android: layout_height=\"wrap_content\" Android: text=\"Button\" /> </LinearLayout> The java controller for a fraction looks as if: Import android.Fragment.App.Fragment; Public magnificence fragment extends fragment @override Public view oncreateview (layoutinflater inflater, viewgroup determine, bundle savedinstancestate) // defines the xml report for the fragment Return inflater.Inflate(r.format.Fragment_oof, parent,false); // any view setup have to occur right here. @override Public void onviewcreated (view view, package deal savedinstancestate) // setup any handles to view objects here // edittexteto = (edittext) view. Findviewbyid(r.Identity.Eto); Embedding a Fragment in an Activity There are two approaches to add a fraction to an activity: dynamically the usage of java and statically using XML. Earlier than embedding a \"guide\" fragment in interest make certain the interest is modified to extend from fragment activity or appcompatactivity which adds help for the fragment 39 CU IDOL SELF LEARNING MATERIAL (SLM)

supervisor to all android version. Any activity the use of fragments should make sure to increase from fragment acitivity or appcompatactivity: Import android. appcompat.App.Appcompatactivity; Public magnificence MainActivity extends appcompatactivity // ... Statically To feature the fragment statically, definitely embed the fragment within the interest's xml layout document: <?Xml version= \"1.0\" encoding= \"utf-8\"?> <LinearLayout xmlns: android=\"http://schemas.Android.Com/apk/res/android\" Android: layout_width=\"match_parent\" Android: layout_height=\"match_parent\" Android: orientation=\"vertical\" > <fragment Android: name=\"com. Example1.Android. OFragment\" Android:id=\"@+id/oFragment\" Android: layout_width=\"match_parent\" Android: layout_height=\"match_parent\" /> </LinearLayout> Dynamically The second manner is via adding the fragment dynamically in java the use of the fragment manager. The fragment manager and the fragment transaction assist you to upload, put off and replace fragments within the format of your activity at runtime. In this example, you need to add a \"placeholder\" container (generally a body layout) to your interest wherein the fragment is inserted at runtime: <?XML version= \"1.0\" 40 CU IDOL SELF LEARNING MATERIAL (SLM)

encoding= \"utf-8\"?> <LinearLayoutxmlns: android=\"http://schemas.android.com/apk/res/android\" android: layout_width=\"match_parent\" android: layout_height=\"match_parent\" android: orientation=\"vertical\" > <FrameLayout android:id=\"@+id/your_placeholder\" android: layout_width=\"match_parent\" android: layout_height=\"match_parent\"> </FrameLayout> </LinearLayout> and then you can use the Fragment Manager to create a Fragment Transaction which allows us to add fragments to the FrameLayout at runtime: // Begin the transaction FragmentTransaction ft1 =getSupportFragmentManager(). beginTransaction(); // Replace the contents of the container with the new fragment ft1.replace(R.id.our_placeholdr,new oFragment()); // or ft1.add(R.id.our_placeholdr, new oFragment()); // Complete the changes added above ft1.commit(); If the fragment should always be within the activity, use XML to statically add the fragment but in more complex cases be sure to use the Java-based approach. 3.2TYPES OF FRAGMENTS Basically, fragments are divided as three stages as shown below. 1. Single frame fragments – Single frame fragment is designed for small screen devices such as handheld devices(mobiles) and it should be above the android 3.0 version. Example This example will explain to you how to create your own Fragments. Here we will create two fragments and one of them will be used when the device is in landscape mode and another fragment will be used in the case of portrait mode. So, let's follow the following steps to similar to what we followed while creating Hello World Example − 41 CU IDOL SELF LEARNING MATERIAL (SLM)

Step Description 1 You will use Android Studio IDE to create an Android application and name it as MyFragments under a package com.example1.myfragments, with blank Activity. 2 Modify main activity file MainActivity.java as shown below in the code. Here we will check orientation of the device and accordingly we will switch between different fragments. 3 Create a two java files PM_Fragment.java and LM_Fragement.java under the package com.example1.myfragments to define your fragments and associated methods. 4 Create layouts files res/layout/lm_fragment.xml and res/layout/pm_fragment.xml and define your layouts for both the fragments. 5 Modify the default content of res/layout/activity_main.xml file to include both the fragments. 6 Define required constants in res/values/strings.xml file 7 Run the application to launch Android emulator and verify the result of the changes done in the application. Following is the content of the modified main activity file MainActivity.java − 42 package com.example1.myfragments; import android.app.Activity; import android.app.FragmentManager; import android.app.FragmentTransaction; import android.content.res.Configuration; import android.os.Bundle; public class MainActivity extends Activity { CU IDOL SELF LEARNING MATERIAL (SLM)

/** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Configuration config = getResources().getConfiguration(); FragmentManager fragmentManager = getFragmentManager(); 43 FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); /** * Check the device orientation and act accordingly */ if (config.orientation == Configuration.ORIENTATION_LANDSCAPE) { /** * Landscape mode of the device */ LM_Fragementls_fragment = new LM_Fragement(); fragmentTransaction.replace(android.R.id.content, ls_fragment); }else{ /** * Portrait mode of the device */ PM_Fragementpm_fragment = new PM_Fragement(); fragmentTransaction.replace(android.R.id.content, pm_fragment); } fragmentTransaction.commit(); } } Create two fragment files LM_Fragement.java and PM_Fragment.java Following is the content of LM_Fragement.java file − package com.example1.myfragments; CU IDOL SELF LEARNING MATERIAL (SLM)

import android.app.Fragment; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; public class LM_Fragement extends Fragment { @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { /** * Inflate the layout for this fragment */ return inflater.inflate(R.layout.lm_fragment, container, false); } } Following is the content of the PM_Fragement.java file − package com.example1.myfragments; import android.app.Fragment; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; public class PM_Fragement extends Fragment { 44 @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { /** CU IDOL SELF LEARNING MATERIAL (SLM)

* Inflate the layout for this fragment */ return inflater.inflate(R.layout.pm_fragment, container, false); } } Create two layout files lm_fragement.xml and pm_fragment.xml under res/layout directory. Following is the content of lm_fragement.xml file − <?xml version=\"1.0\" encoding=\"utf-8\"?> <LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\" android:orientation=\"vertical\" android:layout_width=\"fill_parent\" android:layout_height=\"fill_parent\" android:background=\"#7bae16\"> <TextView android:layout_width=\"fill_parent\" android:layout_height=\"wrap_content\" android:text=\"@string/landscape_message\" android:textColor=\"#000000\" android:textSize=\"20px\" /> <!-- More GUI components go here --> </LinearLayout> 45 Following is the content of pm_fragment.xml file − <?xml version=\"1.0\" encoding=\"utf-8\"?> <LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\" android:orientation=\"horizontal\" CU IDOL SELF LEARNING MATERIAL (SLM)

android:layout_width=\"fill_parent\" android:layout_height=\"fill_parent\" android:background=\"#666666\"> <TextView android:layout_width=\"fill_parent\" android:layout_height=\"wrap_content\" android:text=\"@string/portrait_message\" android:textColor=\"#000000\" android:textSize=\"20px\" /> <!-- More GUI components go here --> </LinearLayout> Following will be the content of res/layout/activity_main.xml file which includes your fragments − <?xml version=\"1.0\" encoding=\"utf-8\"?> <LinearLayoutxmlns:android=\"http://schemas.android.com/apk/res/android\" xmlns:tools=\"http://schemas.android.com/tools\" android:layout_width=\"fill_parent\" android:layout_height=\"fill_parent\" android:orientation=\"horizontal\"> <fragment android:name=\"com.example1.fragments\" android:id=\"@+id/lm_fragment\" android:layout_weight=\"1\" android:layout_width=\"0dp\" android:layout_height=\"match_parent\" /> <fragment android:name=\"com.example1.fragments\" android:id=\"@+id/pm_fragment\" android:layout_weight=\"2\" 46 CU IDOL SELF LEARNING MATERIAL (SLM)

android:layout_width=\"0dp\" android:layout_height=\"match_parent\" /> </LinearLayout> Make sure you have following content of res/values/strings.xml file − <?xml version=\"1.0\" encoding=\"utf-8\"?> <resources> <string name=\"app_name\">My Application</string> <string name=\"landscape_message\">This is Landscape mode fragment</string> <string name=\"portrait_message\">This is Portrait mode fragment></string> </resources> List fragments − framework's ListFragment is supported by Static library version prior to Android 3.0. The basic implementation of list fragment is for creating list of items in fragments Figure 3.2. List in Fragments Example This example will explain you how to create your own list fragment based on arrayAdapter. So let's follow the following steps to similar to what we followed while creating Hello World Example − 47 CU IDOL SELF LEARNING MATERIAL (SLM)

Step Description 1 You will use Android Studio to create an Android application and name it as SimpleListFragment under a package com.example1.ts7.myapplication, with blank Activity. 2 Modify the string file, which has placed at res/values/string.xml to add new string constants 3 Create a layout called list_fragment.xml under the directory res/layout to define your list fragments. and add fragment tag(<fragment>) to your activity_main.xml 4 Create a List_Fragment .java, which is placed at java/List_Fragment .java and it contained onCreateView(),onActivityCreated() and OnItemClickListener() 5 Run the application to launch Android emulator and verify the result of the changes done in the application. Before coding we will initialize the string constants in 48 string.xml file <?xml version=\"1.0\" encoding=\"utf-8\"?> <resources> <string name=\"app_name\">List_Fragment_Demo</string> <string name=\"action_settings\">Settings</string> <string name=\"hello_world\">Hello world!</string> <string name=\"img_desc\">imgdesc</string> <string-array name=\"Planets\"> <item>Sun</item> <item>Mercury</item> <item>Venus</item> CU IDOL SELF LEARNING MATERIAL (SLM)

<item>Earth</item> <item>Mars</item> <item>Jupiter</item> <item>Saturn</item> <item>Uranus</item> <item>Neptune</item> </string-array> </resources> Following will be the content of res/layout/activity_main.xml file. Containing linear layout and fragment tag. <?xml version=\"1.0\" encoding=\"utf-8\"?> <LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\" android:layout_width=\"match_parent\" android:layout_height=\"match_parent\" android:orientation=\"vertical\" > <fragment android:id=\"@+id/fragment1\" android:name=\"com.example1.ts7.myapplication.List_Fragment \" android:layout_width=\"match_parent\" android:layout_height=\"match_parent\" /> </LinearLayout> Following will be the content of res/layout/list_fragment.xml file. it contained linear layout,list view and text view <?xml version=\"1.0\" encoding=\"utf-8\"?> <LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\" 49 CU IDOL SELF LEARNING MATERIAL (SLM)

android:layout_width=\"match_parent\" android:layout_height=\"match_parent\" android:orientation=\"vertical\" > <ListView android:id=\"@android:id/list\" android:layout_width=\"match_parent\" android:layout_height=\"wrap_content\" > </ListView> <TextView android:id=\"@android:id/empty\" android:layout_width=\"match_parent\" android:layout_height=\"wrap_content\" > </TextView> </LinearLayout> the following will be the content of the src/main/java/List_Fragment .java file. before writing to code, need to follow few steps as shown below • Create a class List_Fragment and extend it to ListFragment. • Inside the onCreateView() method, inflate the view with the above-defined list_fragment XML layout. • Inside the onActivityCreated() method, create an arrayadapter from resource ie using String array R.array.planet which you can find inside the string.xml and set this adapter to listview and also set the onItem click Listener. • Inside the OnItemClickListener() method, display a toast message with the Item name which is being clicked. package com.example1.ts7.myapplication; 50 import android.annotation.SuppressLint; import android.app.ListFragment; import android.os.Bundle; CU IDOL SELF LEARNING MATERIAL (SLM)