Software Engineering Large Practical: Android Development

Transcription

1 Software Engineering Large Practical: Android Development School of Informatics September 25th, 2013

2 Getting the Android SDK

3 Getting the Android SDK

4 Getting the Android SDK

5 Getting the Android SDK

6 Getting the Android SDK

7 Getting the Android SDK

8 Getting the Android SDK

9 Getting the Android SDK

10 Creating a new Android project

11 Naming your project

12 Specifying the platform

13 Market share of Android versions ng

14 Creating an Android Virtual Device An Android Virtual Device (AVD) is an emulator configuration which allows the developer to replicate the effect of having an actual Android device such as a phone or a tablet. The AVD allows you to specify hardware and software settings which will be emulated by the Android Emulator. When creating a new AVD you specify the target API (i.e. a particular version of Android).

15 Creating an emulator

16 Android Virtual Device (AVD) manager

17 Create a new AVD (Click New...)

18 Create new Android Virtual Device png

19 Starting the emulator Having defined the type of AVD that we are interested in, we can start one running and investigate the functions of our virtual device.

20 Start the new AVD png

21 Launch Options png

22 Emulator launches png

23 Emulator home page is displayed png

24 Click to display options png

25 Functions of the phone png

26 Looking at samples

27 A project is created

28 Configuring an Android application

29 Run configurations

30 Setting the DNS server

31 Running an Android application

32 Starting the activity on the emulator

33 The emulator running ng

34 Searching the dictionary ng

35 Autocompletion is used ng

36 The application in the launchpad ng

37 Managing apps on the phone ng

38 Selecting an app for deletion ng

39 Forcing apps to stop ng

40 Forcing apps to stop ng

41 Uninstalling an app ng

42 Uninstalling an app ng

43 Uninstalling an app ng

44 Developer tools There are some tools on the device which are specifically there to help developers (API Demos and Dev Tools). The developer tools allow us to see (for example) processes which are running on the phone.

45 Useful functions png

46 Developer Tools png

47 Running processes png

48 API demos There are some tools on the device which are specifically there to help developers (API Demos and Dev Tools). Using these we can learn about the Android API features such as auto-completion.

49 Useful functions png

50 API demos png

51 API demos png

52 API demos png

53 Auto-complete contacts png

54 Seeding a NullPointerException (NPE)

55 Try to run the application

56 User view of a NullPointerException ng

57 Change the Eclipse perspective

58 Dalvik Debug and Monitor Service

59 DDMS perspective with LogCat ng

60 Developer view of a NPE

61 Tracking the error back to the code

62 Error found, warning visible

63 Bug removed, Java Problem disappears

64 Eclipse DDMS perspective The Dalvik Debug Monitor Server (DDMS) is a debugging tool for Android. It provides port-forwarding services and screen capture on the device. It provides information about process, threads and heap usage. It contains the logcat console which allows us to see diagnostic error messages. It allows the developer to simulate the effect of an incoming call or SMS, or to simulate setting the phone s location.

65 DDMS perspective in Eclipse

66 Set your location

67 LogCat a log of events on the phone

68 File Explorer see files on the phone png

69 Devices see processes in the emulator png

70 Allocation tracker png

71 Graphical view of XML in editor

72 Source code view of XML in editor

73 Outline view of XML in editor

74 The editor (and themes)

75 Changing the theme (Holo light)

76 Changing the theme (Theme Light)

77 Adding widgets with drag and drop

78 The graphical layout is updated

79 XML source automatically updated too

80 Undo changes in the editor

81 Errors in XML code ng

82 Errors in XML can be subtle ng

83 Android Eclipse issues Working with hand-crafted and automatically-generated Java files can be confusing. In particular we focus on errors involving the automatically-generated R.java file.

84 Oh no, Java problems...

85 Layout cannot be resolved...

86 R.java is generated so clean the project?

87 No good. Delete R.java and try again?

88 R.java is regenerated but errors remain

89 Refresh the view?

90 No good. What now?

91 Close the project and reopen it?

92 Reopening the project. Praying...

93 Didn t work :-( but look at this...

94 Moving the folder fixes the problem :-)

95 Moving the folder fixes the problem :-)

96 Manifest files Every Android application must have an AndroidManifest.xml file (with precisely that name) in its root directory. The manifest presents essential information about the application to the Android system, including information about intents which are messages sent to activities, services and broadcast receivers. The manifest also specifies permissions which the application requests (such as the permission to connect to paired Bluetooth devices) and libraries that it needs.

97 Manifest files

98 The manifest editor

99 Adding extras ng

100 Labels and icons

101 Application nodes and intents ng

102 Attributes for an action

103 Add permissions

104 Add instrumentation

105 Source code view

106 Source code tab.png

107 Resources and strings An Android application may need resources such as image files and strings. A string resource provides text strings for the application with optional text styling and formatting.

108 Resources and strings

109 A String resource, app name

110 Managing string resources

111 Drawable resources

112 Managing drawable resources

113 Contents of app notes.png

114 The icon in the launcher view

115 Editing string resources String resources can be edited using the Android Resources editor.

116 Application nodes

117 Browsing

118 Editing strings

119 Updating a string

120 Text in the XML view

121 Updating a string in the Resources view

122 The XML text is updated automatically

123 Getting it wrong: editing the XML

124 The bug shows up in the resources view

125 Oh dear