SurfaceCallback.java
/*
* Copyright 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.car.app;
import android.graphics.Rect;
import androidx.annotation.NonNull;
/** A callback for changes on the {@link SurfaceContainer} and its attributes. */
public interface SurfaceCallback {
/**
* Provides a {@link SurfaceContainer} from the host which is ready for drawing.
*
* <p>This method may be called multiple times if the surface changes characteristics. For
* instance, the size or DPI may change without the underlying surface being destroyed.
*
* <p>This method is guaranteed to be called before any other methods on this listener.
*
* @param surfaceContainer The {@link SurfaceContainer} that is ready for drawing
*/
void onSurfaceAvailable(@NonNull SurfaceContainer surfaceContainer);
/**
* Indicates that the visible area provided by the host has changed.
*
* <p>The visible area may be occluded for several reasons including status bar changes,
* overlays from other apps or dynamic UI within a template. The inset is the area currently
* guaranteed to not be occluded by any other UI. If the app needs to show critical data, it
* should be within the inset area.
*
* @param visibleArea The rectangle set to the surface area guaranteed to be visible. If {@link
* Rect#isEmpty()} returns {@code true} for the visible area, then it is
* currently unknown
*/
void onVisibleAreaChanged(@NonNull Rect visibleArea);
/**
* Indicates that the stable area provided by the host has changed.
*
* <p>The visible area (see {@link #onVisibleAreaChanged} can be occluded for several reasons
* including status bar changes, overlays from other apps or dynamic UI within the template. The
* stable area is the visual area which will not be occluded by known dynamic content. The area
* may change at any time, but every effort is made to keep it constant.
*
* @param stableArea Inset rectangle of the surface space designated as stable. If {@link
* Rect#isEmpty()} returns {@code true} for the stable area, then it is
* currently unknown
*/
void onStableAreaChanged(@NonNull Rect stableArea);
/**
* Indicates that the {@link SurfaceContainer} provided by the host will be destroyed after this
* callback.
*
* @param surfaceContainer the {@link SurfaceContainer} being destroyed
*/
void onSurfaceDestroyed(@NonNull SurfaceContainer surfaceContainer);
}