The document discusses several new features and APIs in Android 3.0 (Honeycomb) for tablets, including fragments which allow recomposing UI based on factors like screen size, loaders for asynchronously fetching content, an enhanced action bar for navigation and menus, hardware accelerated graphics, and the new holographic UI design. It also questions what some aspects of Android 3.0 may mean for future phone releases and how to detect "tablet-y" systems.

1. Robert Cooper
Reach Health

2.  Tablet-specific version of Android
 New UI Metaphors
 New LaF (Holographic)
 New/Improved APIs.
 Old APIs made optional (telephony, etc)
 New Technologies
 Basis for future releases
 3.1 seems to be on-deck
 Merged with phone branch?

3.  Hopefully everything, at least briefly.
 Detailed discussion of the things I just you
are most likely to care about as a
developer :P

4.  ActionBar
 Used for “App Global” Tabs
 Special MenuItems or SubMenus
 App Icon with a “Logical Home” operation
 No Hard Buttons
 NotificationBar now includes “Back”, “Home”
and “Tasks”
 Long-Touch context menus deprecated as
a model

6.  Holographic look and feel added
 Make it more TRON-ish…
 … but not too TRON-ish
 Lots of glows, varied depth line
markers, 3D transitions
 Improved text ops mechanics

10.  Fragments
 Sub-Activities
 Loaders
 Async-Friendly Content Fetchers
 ActionBar
 New Menuing and Nav System.
 Enhanced Interaction for Widgets and
Notifications
 Drag and Drop

11.  Fragments
 Fragments are Sub-Activities that can be
recomposed based on UI factors (screen
size, orientation, etc)
 Part of 3.0, but available as a build-in backport
as far back as 1.6 with the “Android
Compatibility Package” (Available in the
SDK/AVD Manager)

12.  Fragments mimic Activity lifecycle:
 onCreate()
 onStart()
 onCreateView()*
 onPause()
 onStop()

13.  Fragments laid out as part of Layouts
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment android:name="com.example.news.ArticleListFragment"
android:id="@+id/list"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="match_parent" />
<fragment
android:name="com.example.news.ArticleReaderFragment"
android:id="@+id/viewer"
android:layout_weight="2"
android:layout_width="0dp"
android:layout_height="match_parent" />
</LinearLayout>

14.  Each Fragment becomes unique in the
application
 Can move between Activities with different
combinations of Fragments by passing
Fragment model/URI information using
the FragmentManager API.
 FragmentTransaction can be used to
manipulate fragment state and “back”
behavior

15.  FragmentTransaction
Fragment newFragment = new ExampleFragment();
FragmentTransaction transaction =
getFragmentManager().beginTransaction();
transaction.replace(R.id.fragment_container, newFragmen
t);
transaction.addToBackStack(null);
transaction.commit();

16.  Loaders provide a standard way to load
data for Fragments
 AsyncTaskLoader provides API for loading
data asynchronously
 CursorLoader loads a paged dataset
asynchronously – this is likely what you
want to read, for example, an Atom Pub
Proto data source remotely.

17.  Moving MenuItems to the ActionBar
<?xml version="1.0" encoding="utf-8"?>
<menu
xmlns:android="http://schemas.android.com/apk/res/android"
>
<item android:id="@+id/menu_add"
android:icon="@drawable/ic_menu_save"
android:title="@string/menu_save"
android:showAsAction="ifRoom|withText" />
</menu>

18.  Custom Views in ActionBar
<?xml version="1.0" encoding="utf-8"?>
<menu
xmlns:android="http://schemas.android.com/apk/res/andro
id">
<item android:id="@+id/menu_search"
android:title="Search"
android:icon="@drawable/ic_menu_search"
android:showAsAction="ifRoom"
android:actionLayout="@layout/searchview"
android:actionViewClass="android.widget.SearchView"
/>
</menu>

19.  Custom Views in ActionBar (cont)
SearchView searchView = (SearchView)
menu.findItem(R.id.menu_search).getActionView
();

20.  Navigation
 Big win over iOS!
 Implicit “Home” widget (vs iOS Nav Bar)
 App Global Tabs (vs iOS Tool Bar)
 App List Navigation

21.  Getting the “Home” icon view
View home = a.findViewById(android.R.id.home);
home.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
a.finish();
}
});
 Adding “Up” marker
ActionBar actionBar = this.getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);

22.  ActionBar Tabs
final ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(
ActionBar.NAVIGATION_MODE_TABS);
// remove the activity title to make space for tabs
actionBar.setDisplayShowTitleEnabled(false);
Fragment artistsFragment = new ArtistsFragment();
actionBar.addTab(actionBar.newTab()
.setText(R.string.tab_artists)
.setTabListener(new TabListener(artistsFragment)));
Fragment albumsFragment = new AlbumsFragment();
actionBar.addTab(actionBar.newTab()
.setText(R.string.tab_albums)
.setTabListener(new TabListener(albumsFragment)));

23.  ActionBar List (Spinner) Navigation
ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(
ActionBar.NAVIGATION_MODE_LIST);
actionBar.setListNavigationCallbacks(
new SpinnerAdapter(){
public View getDropDownView(int position,
View convertView, View Group parent){
// …
}
}, new OnNavigationListener(){
public boolean onNavigationItemSelected(
int itemPosition, long itemId){
//…
}
});

24.  Notifications can now use RemoteViews to
allow interaction with the popup notification,
rather than just launch an intent.
RemoteViews layout = new RemoteViews(
getPackageName(), R.layout.notification);
notification.contentView = layout;
layout.setOnClickPendingIntent(
R.id.my_button,
getDialogPendingIntent(
"You pressed it!"));

25. PendingIntent getDialogPendingIntent(
String dialogText) {
return PendingIntent.getActivity(
this, // send back to the creating Act.
dialogText.hashCode(),
new Intent(ACTION_DIALOG)
.putExtra(Intent.EXTRA_TEXT,
dialogText)
.addFlags(
Intent.FLAG_ACTIVITY_NEW_TASK),
0);
}

26. Handling the PendingIntent:
if (ACTION_DIALOG.equals(intent.getAction())) {
showDialog(
intent.getStringExtra(
Intent.EXTRA_TEXT))
}
PendingIntent then becomes an invisible
call back into your Activity.

27.  Any View can now be dragged about the
screen.
 To begin a drag action call:
myView.startDrag(
dragData, dragShadowBuilder, localData,
 0 /*unused int flags */);
 Can be called from you
OnClick/OnLongClick listeners…
 localData is just any Object that will be
sent with each DragEvent.

28.  dragData: is a ClipData object. This
contains the data representation of what is
being dragged:
ClipData.Item item =
new ClipData.Item(v.getTag());
ClipData dragData = new ClipData(v.getTag(),
ClipData.MIMETYPE_TEXT_PLAIN,item);
Be sure to use the “tag” property for your
model data!

29.  Create the DrawShadowBuilder. This returns the
view that is dragged about under the pointer.
 This class takes a View as an argument and
looks a lot like the stock View paint lifecycle.
@Override
public void onProvideShadowMetrics (Point
size, Point touch)
@Override
public void onDrawShadow(Canvas canvas)
 The first method sets the bounds, the second
paints to the canvas.
 You can use the View’s existing draw() method
then mutate it

30.  DragEvents
 onDragEvent(DragEvent) or
View.OnDragListener on any view (These are
really for Drop Targets)
 DragEvent.getAction() returns one of the
possible event action types.

31.  ACTION_DRAG_STARTED
 Sent to all active Views – check here for drop target
validity!
 ACTION_DRAG_ENTERED
 Sent when the touch enters the box of the View
 ACTION_DRAG_LOCATION
 Sent on each move while in the box of the View
 ACTION_DRAG_EXITED
 Sent when the touch leaves the box.
 ACTION_DROP
 Sent on drop event *ONLY* when the View/Listener
returned “true” from the ACTION_DRAG_STARTED
event.

32.  Support for Hardware Accelerated Graphics
 Applies to stock animations and drawing APIs
 Comes damned near for free but…
 … if you haven’t tested it, it doesn’t work.
 Romain Guy eats his words! :P
 Property animation
 RenderScript
 A C99-ish script for doing OpenGL ops
 Should be like falling off a log for people with
OpenCL experience (read: not me)

33.  Activation/Deactivation
 Step 1: Add…
android:hardwareAccelerated="true|false“
…to your <application> or <activity>
 Step 2: Profit!

34.  Looks a whole lot like every other
reflective animator (Swing-X, Gwittir, Moo
Tools, etc)
 Lots of possible options, but easily
summarized:
ObjectAnimator anim = ObjectAnimator.ofFloat(
someObject, “someProperty", startValue, endValue);
anim.setInterpolater( someInterpolater );
anim.setDuration(1000);
anim.start();

35.  Lots of stock interpolators (mutation
strategies)
 AccelerateDecelerateInterpolator : Sinoidal
 AccelerateInterpolator : Geometric
 AnticipateInterpolator : Start backwards, then fling
forward
 BounceInterpolator : Bounces around the end
value
 Linear Interpolator : Even steps
 “And many, many more!”

36.  Not even going to get into this. Example from Google:
#pragma version(1)
#pragma rs java_package_name(com.android.example.hellocompute)
rs_allocation gIn;
rs_allocation gOut;
rs_script gScript;
const static float3 gMonoMult = {0.299f, 0.587f, 0.114f};
void root(const uchar4 *v_in, uchar4 *v_out, const void
*usrData, uint32_t x, uint32_t y) {
float4 f4 = rsUnpackColor8888(*v_in);
float3 mono = dot(f4.rgb, gMonoMult);
*v_out = rsPackColorTo8888(mono);
}
void filter() {
rsForEach(gScript, gIn, gOut, 0);
}

37.  DownloadManager API is VASTLY
improved over the Gingerbread version!
 It is actually usable now!
 HTTP Live Streaming support
 Improved SIP API over Gingerbread.
 Accessibility improvements

38.  Still questions about what API 12 will mean
 ActionBar/New Notifications on Phones? Is that a
good idea?
 Keeping phones with the current menu strategy?
 How to detect “Tablet-y” systems?
 Google TV?
 Lots and Lots of “Reflectively constructed
strategies” – I it is manageable, but getting
harder to support older devices