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A user can exit an Android Wear activity by swiping from left to right. If the app has horizontal scrolling (e.g., the type of scrolling available in an app containing maps), a user exits by navigating to the edge of the content and then swiping from left to right.
Pressing the power button returns the user to the watch face.
The Swipe-To-Dismiss Gesture
Users swipe from left to right to close the current screen. Therefore, it is recommended that you utilize the following:
It also is recommended that your app does not contain horizontal swiping gestures.
Dismissal of an activity
An activity automatically supports swipe-to-dismiss. Swiping an activity from left to right results in dismissal of the activity, and the app navigates down the back stack.
Fragments
You can wrap a fragment-containing view in the
SwipeDismissFrameLayout class, as follows:
public class SwipeDismissFragment extends Fragment {
private final Callback mCallback =
new Callback() {
@Override
public void onSwipeStart() {
// optional
}
@Override
public void onSwipeCancelled() {
// optional
}
@Override
public void onDismissed(SwipeDismissFrameLayout layout) {
// Code here for custom behavior such as going up the
// back stack and destroying the fragment but staying in the app.
}
};
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
SwipeDismissFrameLayout swipeLayout = new SwipeDismissFrameLayout(getActivity());
// If the fragment should fill the screen (optional), then in the layout file,
// in the android.support.wearable.view.SwipeDismissFrameLayout element,
// set the android:layout_width and android:layout_height attributes
// to "match_parent".
View inflatedView = inflater.inflate(R.layout.swipe_dismiss_frame_layout, swipeLayout, false);
swipeLayout.addView(inflatedView);
swipeLayout.addCallback(mCallback);
return swipeLayout;
}
}
Horizontal scrollable views
In some cases, such as in a view containing a map that supports panning, the user interface would not prevent horizontal swiping. In this scenario, there are two choices:
- If the back stack is short, the user can dismiss the app and return to the home screen (watch face) by pressing the power button.
- If you want the user to go down the back stack, you can wrap the view
in a
SwipeDismissFrameLayoutobject, which supports edge swipe. Edge swipe is enabled when the view or its children returnstruefrom acanScrollHorizontally()call. Edge swipe enables the user to dismiss the view by swiping from the leftmost side of the screen (currently set to 10% of the screen width) and not just anywhere in the view.
To wrap a view in a SwipeDismissFrameLayout object, review
the following examples:
XML for a layout file
<android.support.wearable.view.SwipeDismissFrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/swipe_dismiss_root" >
<TextView
android:id="@+id/test_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:text="Swipe me to dismiss me." />
</android.support.wearable.view.SwipeDismissFrameLayout>
Code snippet
SwipeDismissFrameLayout testLayout =
(SwipeDismissFrameLayout) activity.findViewById(R.id.swipe_dismiss_root);
testLayout.addCallback(new SwipeDismissFrameLayout.Callback() {
@Override
public void onDismissed(SwipeDismissFrameLayout layout) {
layout.setVisibility(View.GONE);
}
}
);
Generally not recommended: Disabling swipe-to-dismiss
Disabling swipe-to-dismiss generally is not recommended because the user
expects to dismiss any screen with a swipe. In an exceptional case,
you can extend the default theme
(in a
style resource)
and set the android:windowSwipeToDismiss attribute
to false:
<resources>
<style name="AppTheme" parent="@android:style/Theme.DeviceDefault">
<item name="android:windowSwipeToDismiss">false</item>
</style>
</resources>
You can then inform users (on their first use of your app) that they can exit the app by pressing the power button.
Dismissal behavior before Wear 2.0
Before Wear 2.0, the DismissOverlayView class was
used to implement the long-press for a user to dismiss an app.
The DismissOverlayView class no longer should be used.
Additionally, long-pressing to dismiss an app is no longer suggested. Do not implement the long-press for dismissing full screen activities (panning or immersive activities such as Google Maps).
Dismissal via the Power Button
A press of the power (hardware) button sends a power key event. Therefore, you cannot use the power button as a back button or for navigation in general.
When pressed, the power button returns the user to the home screen (watch face). There are two exceptions:
- If the user is in an IME (an Input Method Editor, e.g. a handwriting recognition screen), pressing the button closes the IME and returns the user to the app.
- If the user is at the watch face, pressing the hardware button opens the app launcher.
Note that when the power button is pressed, the
isFinishing() method of the Activity class does
not return true (nor can you intercept the key event).