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Sample Apps
The swipe-to-refresh user interface pattern is implemented entirely within
the SwipeRefreshLayout
widget, which
detects the vertical swipe, displays a distinctive progress bar, and triggers
callback methods in your app. You enable this behavior
by adding the widget to your layout file as the parent of a ListView
or GridView
, and implementing
the refresh behavior that gets invoked when the user swipes.
This lesson shows you how to add the widget to an existing layout. It also shows you how to add a refresh action to the action bar overflow area, so that users who may be unable to use the swipe gesture can trigger a manual update with an external device.
Add the SwipeRefreshLayout Widget
To add the swipe to refresh widget to an existing app, add SwipeRefreshLayout
as the parent
of a single ListView
or GridView
. Remember that SwipeRefreshLayout
only supports a single ListView
or GridView
child.
The following example demonstrates how to add the SwipeRefreshLayout
widget to an existing layout
file containing a ListView
:
<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/swiperefresh" android:layout_width="match_parent" android:layout_height="match_parent"> <ListView android:id="@android:id/list" android:layout_width="match_parent" android:layout_height="match_parent" /> </android.support.v4.widget.SwipeRefreshLayout>
You can also use the SwipeRefreshLayout
widget with a ListFragment
. If the layout
contains a ListView
with the ID
"@android:id/list"
, the swipe-to-refresh functionality is
automatically supported. However, explicitly declaring the ListView
in this way supersedes the default ListFragment
view structure. If you want to use the
default view structure, you will have to override parts of the SwipeRefreshLayout
and ListFragment
behavior. For an example of how to do
this, see the SwipeRefreshListFragment
sample app.
Add a Refresh Action to the Action Bar
You should add a refresh action to your app's action bar to ensure that users who may not be able to perform a swipe gesture can still trigger a manual update. For example, users with accessibility issues can trigger action bar actions using external devices, such as keyboards and D-pads.
You should add the refresh action as a menu item,
rather than as a button, by setting the attribute
android:showAsAction=never
. If you display the action as a
button, users may assume that the refresh button action is different from the
swipe-to-refresh action. By making the refresh action less conspicuous in the
action bar, you can encourage users to perform manual updates with the swipe
gesture while still maintaining the accessible option in a place where D-pad
users would look for it.
The following code demonstrates how to add the swipe-to-refresh action to the overflow area:
<menu xmlns:android="http://schemas.android.com/apk/res/android" > <item android:id="@+id/menu_refresh" android:showAsAction="never" android:title="@string/menu_refresh"/> </menu>