Lecture about some advanced themes in Android development. Faculty of Informatics, Masaryk University, 2014

1. Android Development
201
Tomáš Kypta

2. Android Wear

3. Android Wear
• extension to Android platform
• wearable devices

7. Android Wear
• UI core functions
• Suggest
• Demand

8. Android Wear
• Suggest: The Context Stream

9. Android Wear
• Demand: The Cue Card

10. Android Wear
• Developer Preview
• Notifications
• Voice input from a notification
• Notifications with additional pages

11. Design Patterns

12. ActionBar
• dedicated piece of UI at the top of each screen
• consistent navigation
• important actions
• app identity

13. ActionBar
• navigation up the hierarchy

14. ActionBar
• can have up to 3 parts
• main action bar
• top bar (tab bar)
• bottom bar
• layout differs for portrait and
landscape

15. Navigation Drawer
• panel that transitions from the left edge of the
screen
• displays the app’s main navigation options

16. Multi-pane layouts
• many different screen sizes and types of devices
• provide balanced and aesthetically pleasing layout

17. Multi-pane layouts
• do not forget different orientations
• strategies
• stretch/compress
• adjust the left column width
!
!
• stack
• rearrange the panels

18. Multi-pane layouts
• strategies
• expand/collapse
• show only the most important
information in the left panel
!
!
• show/hide
• in portrait behave like phone

19. Swipe views

20. Swipe views
• allow efficient navigation between items
• swiping between detail views
• swiping between tabs

21. Swipe-to-dismiss
• dismiss list item by swiping left or right

22. Swipe-to-dismiss with Undo

23. Pull-to-refresh
• refresh list by pulling down
• different on Android and iOS

24. Selection
(contextual action bar)
• use long press gesture to select data
• contextual action bar is a temporary action bar

25. Libraries for Android
Development

26. Libraries
• saves time and work
• it might be painful without libraries
• back-porting new API to older Android versions
• simplifying API

27. Libraries
• The ideal library?
• “perform one task and perform it well”
• open-source

28. ActionBar
• ActionBarSherlock
• ActionBarCompat
• support-v7

29. Dialogs
• Why do we need a library for dialogs?

30. Dialogs

31. Dialogs
• Let’s simplify
• android-styled-dialogs

32. Dialogs
• android-styled-dialogs
• backports dialogs in Holo theme
• makes styling and using dialogs a piece of cake

33. Dialogs

34. Pull-to-refresh
• ActionBar-PullToRefresh

35. Navigation Drawer
• DrawerLayour
• support-v4
• SlidingMenu
• android-menudrawer

36. Swipe views
• ViewPager
• support-v4

37. Swipe-to-dismiss
• Android-SwipeToDismiss
• SwipeToDismissNOA
• backport to Android 2.x
• SwipeToDismissUndoList
• with undo

38. Networking
• OkHttp
• SPDY support
• Volley
• easier and faster networking

39. REST API
• retrofit
• simple REST client for Android and Java

40. Image loaders
• displaying images from web

41. Image loaders
• Volley
• NetworkImageView
• Picasso
• easy to use
• Android-Universal-Image-Loader
• powerful and flexible library

42. View injection
• getting rid of boilerplate code
• TextView title = (TextView)
findViewById(R.id.title);!
• Butter Knife
• @InjectView(R.id.title) TextView title;!
• can’t be used in libraries

43. Dependency injection
• Dagger

44. Event bus
• Otto
• Guava based event bus

45. IntelliJ IDEA plugins
• android-selector-chapek
• generates drawable selectors from appropriately
named Android resources
• android-butterknife-zelezny
• allows one-click creation of Butterknife view
injections

46. UI debugging
• android-grid-wichterle
• app that shows grid overlay
• helps to verify app design

47. UI debugging
• Scalpel
• debugging tool to uncover
the layers under our app

48. UI niceties
• NineOldAndroids
• backports animation API introduced in Android
3.0
• ViewPagerIndicator
• paging indicator widgets for ViewPager

49. UI niceties
• PagerSlidingTabStrip

50. Unit testing
• Roboelectric
• fest-android
• FEST assertions geared toward testing Android

51. Other
• Guava

52. Developing Libraries

53. Developing Libraries
• jar
• apklib
• aar

54. Developing Libraries
• How to publish?

55. Maven

56. Maven
• project management tool
• dependency management

57. Maven
• repositories
• The Central Repository
• local repository

58. Maven
• Configuration file
• pom.xml

59. Maven
• lifecycle phases
• validate
• compile
• test
• package
• install
• deploy

60. Maven
• android-maven-plugin
• mvn clean package android:deploy android:run

61. Gradle

62. Gradle
• new build system introduced by Google
• DSL
• dependency management through Maven and/or
Apache Ivy

63. ListView & EmptyView

64. ListView & EmptyView
• How to effectively manage list loading and empty
views?

65. ProGuard

66. ProGuard
• shrinking
• obfuscation
• optimizing
• repackaging

67. ProGuard
• build time
• reflection

68. ProGuard
• Configuration file
• proguard.cfg

69. ProGuard
• output files
• dump.txt
• mapping.txt
• seeds.txt
• usage.txt

70. ProGuard
• Decoding Obfuscated Stack Traces
• ReTrace

71. ProGuard
• Decoding Obfuscated Stack Traces
• retrace.sh -verbose mapping.txt
obfuscated_stacktrace.txt

72. Android Lint

73. Android Lint
• static code analysis tool

74. Android Lint
• Correctness
• Security
• Performance
• Usability
• Accessibility
• I18n

75. Android Lint
• lint path_to_my_project!
• IntelliJ IDEA / Android Studio
• Analyze > Inspect Code …

76. Android Lint
• lint --check HardcodedText path_to_my_project!
• lint —html lint-report.html path_to_my_project

77. Android Lint
• Disabling lint checking
• @SupressLint!
• tools:ignore

78. Android Lint
• Config file
• lint.xml

79. Android Lint
• custom lint rules

80. StrictMode

81. StrictMode
• developer tool for detecting accidental wrong
implementation
• detection on current thread
• detection on ony thread

82. Tools Attributes

83. Tools Attributes
• tools:ignore!
• @SuppressLint

84. Tools Attributes
• tools:targetApi!
• @TargetApi

85. Tools Attributes
• Designtime Layout Attributes
• tools:text!
• tools:visibility!
• etc.

86. Tools Attributes
• tools:locale

87. Tools Attributes
• tools:context

88. Tools Attributes
• tools:layout

89. Tools Attributes
• tools:listitem!
• tools:listheader!
• tools:listfooter

90. Traceview

91. Context

92. Context
• interface to global information about an application
environment

93. Context
• Types
• Application
• Activity/Service
• BroadcastReceiver
• ContentProvider

94. Context & Singletons
• Use only application context for singletons

95. Context & UI
• Use only activity context

96. THE END