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WindowManager

public final class WindowManager
extends Object

java.lang.Object
   ↳ androidx.window.WindowManager


Main interaction point with the WindowManager library. An instance of this class allows polling the current state of the device and display, and registering callbacks for changes in the corresponding states.

Summary

Public constructors

WindowManager(Context context)

Gets an instance of the class initialized with and connected to the provided Context.

WindowManager(Context context, WindowBackend windowBackend)

Gets an instance of the class initialized with and connected to the provided Context.

Public methods

WindowMetrics getCurrentWindowMetrics()

Returns the WindowMetrics according to the current system state.

WindowMetrics getMaximumWindowMetrics()

Returns the largest WindowMetrics an app may expect in the current system state.

void registerLayoutChangeCallback(Executor executor, Consumer<WindowLayoutInfo> callback)

Registers a callback for layout changes of the window of the current visual Context.

void unregisterLayoutChangeCallback(Consumer<WindowLayoutInfo> callback)

Unregisters a callback for window layout changes of the window.

Inherited methods

Public constructors

WindowManager

public WindowManager (Context context)

Gets an instance of the class initialized with and connected to the provided Context. All methods of this class will return information that is associated with this visual context.

Parameters
context Context: A visual context, such as an Activity or a ContextWrapper around one, to use for initialization.

WindowManager

public WindowManager (Context context, 
                WindowBackend windowBackend)

Gets an instance of the class initialized with and connected to the provided Context. All methods of this class will return information that is associated with this visual context.

Parameters
context Context: A visual context, such as an Activity or a ContextWrapper around one, to use for initialization.

windowBackend WindowBackend: Backing server class that will provide information for this instance. Pass a custom WindowBackend implementation for testing.

Public methods

getCurrentWindowMetrics

public WindowMetrics getCurrentWindowMetrics ()

Returns the WindowMetrics according to the current system state.

The metrics describe the size of the area the window would occupy with MATCH_PARENT width and height and any combination of flags that would allow the window to extend behind display cutouts.

The value of this is based on the current windowing state of the system. For example, for activities in multi-window mode, the metrics returned are based on the current bounds that the user has selected for the Activity's window.

Returns
WindowMetrics

getMaximumWindowMetrics

public WindowMetrics getMaximumWindowMetrics ()

Returns the largest WindowMetrics an app may expect in the current system state.

The metrics describe the size of the largest potential area the window might occupy with MATCH_PARENT width and height and any combination of flags that would allow the window to extend behind display cutouts.

The value of this is based on the largest potential windowing state of the system. For example, for activities in multi-window mode the metrics returned are based on what the bounds would be if the user expanded the window to cover the entire screen.

Note that this might still be smaller than the size of the physical display if certain areas of the display are not available to windows created for the associated Context. For example, devices with foldable displays that wrap around the enclosure may split the physical display into different regions, one for the front and one for the back, each acting as different logical displays. In this case getMaximumWindowMetrics() would return the region describing the side of the device the associated context's window is placed.

Returns
WindowMetrics

registerLayoutChangeCallback

public void registerLayoutChangeCallback (Executor executor, 
                Consumer<WindowLayoutInfo> callback)

Registers a callback for layout changes of the window of the current visual Context. Must be called only after the it is attached to the window.

Parameters
executor Executor

callback Consumer

unregisterLayoutChangeCallback

public void unregisterLayoutChangeCallback (Consumer<WindowLayoutInfo> callback)

Unregisters a callback for window layout changes of the window.

Parameters
callback Consumer