This document summarizes the key features of Honeycomb, the tablet-optimized version of Android. It introduces the new Holo theme and action bar UI. It describes how to enable these features and add items to the action bar. It explains the new fragment architecture which allows content to dynamically scale for different screen sizes. It covers how to create, display, and manage fragments. It also summarizes new features for app widgets, notifications, animations, and more in Honeycomb.

1. Introducing
Honeycomb

2. Elements of the HC Look & Feel
● Status Bar
– At the bottom now
– Soft keys for HOME, BACK, etc.
● Action Bar
– Combination toolbar, options menu, context
menu, and title bar
● Holographic Theme

3. Enabling the HC Look & Feel
● <uses-sdk android:targetSdkVersion=“11” />
– Gives your widgets the Holographic theme,
unless you overrode it
– Replaces a MENU button in status bar with your
options menu in the action bar

5. Adding to the Action Bar
● android:showAsAction
– ifRoom or always
– withText for text+icon vs. just icon
● android:actionLayout
– Layout resource to inflate into the action bar
instead of a toolbar button

8. Fragments: What and Why
● What: Layer Between Activity and View
– Designed to create internally-reusable facets of
your UI, to be combined based upon screen size
– Can animate on/off, have own BACK stack
● Why: Future Honeycomb-on-Phones
– Tries to simplify having single UI definition that
scales up for larger screens

9. Fragments: User Experience
● Lists With Selection
– Normally, touch mode is an action
● Lists Plus Detail Simultaneously
– ...on tablets
– Phones will have as separate activities due to
limited screen space
● Intra-Activity BACK Operation

10. Fragments: The Mechanics
● Create Fragment Classes
– Extend Fragment, ListFragment, etc.
– Override onCreateView() to define content
● E.g., inflated layout
– Lifecycle Methods
● onActivityCreated()
● onSaveInstanceState()
● Etc.

11. Fragments: The Mechanics
● Displaying Fragments
– Embed in activity layouts via <fragment>
● Large/xlarge layouts have multiple fragments
● Small/normal layouts have single fragment
– Add dynamically via FragmentManager
– FragmentTransaction
● Add, replace, remove, etc.
● Configure if “transaction” can be reversed via BACK

12. Fragments: The Mechanics
● Problem: Backwards Compatibility
– Fragments firmly in API Level 11
– Backwards-compatible fragment
implementation in the works
● Android library project
● Wrapper API that uses Honeycomb if available or
internal implementation if not
● Not available at the time of this writing

13. App Widgets in Honeycomb
● Adapter-Driven Widget Contents
– ListView, GridView, StackView,
AdapterViewFlipper
– RemoteViewsService
● Preview Images
– Shown to user before app widget is added to
screen

14. Notifications in Honeycomb
● What We Gain
– Control over Growl-style large pop-ups
● What We Lose
– number
● What Users Lose
– Single clear button – now individual close
buttons per Notification

15. Animations in Honeycomb
● Animate Arbitrary Properties
– E.g, change colors
– ValueAnimator and ObjectAnimator
– New view properties for rotation, pivot, scale,
etc.
– Can generally replace much of classic animation
framework (translation, rotation, etc.)

16. The Rest of the HC Story
● android:hardwareAccelerated="true"
– Speeds things up, but false by default for
compatibility
● Rich Clipboard Contents
● Drag-and-Drop
– For moving data, not widgets
– Same engine as new clipboard contents

17. The Rest of the HC Story
● Loaders for asynchronous loading of data
– Particularly for use with content providers
● New widgets: CalendarView, SearchView,
NumberPicker, etc.
● Renderscript for 3D work
● Touch events across widgets
● And on, and on, and on...

18. Ice Cream Sandwich
● Current Working Theory
– Android 3.1
– Summer 2011
– Honeycomb UI, other Android 3.0 goodness
brought to phones
● Not everything, due to screen size or lower hardware
requirements