FixedSizeTextureViewImplementation.java
/*
* Copyright 2019 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.camera.view;
import static androidx.camera.view.ScaleTypeTransform.transformCenterCrop;
import android.content.Context;
import android.graphics.Matrix;
import android.graphics.SurfaceTexture;
import android.view.Display;
import android.view.Surface;
import android.view.TextureView;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.FrameLayout;
import androidx.annotation.NonNull;
import androidx.camera.core.Preview;
import androidx.camera.core.impl.utils.executor.CameraXExecutors;
import androidx.camera.core.impl.utils.futures.Futures;
import androidx.core.util.Preconditions;
/**
* A {@link TextureView} implementation for {@link PreviewView} that uses a FixedSizeSurfaceTexture.
* TODO: This is a temporary fix for the distorted preview seen on both PreviewViewFragment and
* CameraViewFragment after onPause/onResume (b/146048690), and will be removed after
* the TextureView's view parameters are modified instead of applying a transform matrix on it.
*/
public class FixedSizeTextureViewImplementation implements PreviewView.Implementation {
private TextureView mTextureView;
private SurfaceTextureReleaseBlockingListener mSurfaceTextureListener;
@Override
public void init(@NonNull final FrameLayout parent) {
mTextureView = new TextureView(parent.getContext());
mTextureView.setLayoutParams(
new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
FrameLayout.LayoutParams.MATCH_PARENT));
// Access the setting of the SurfaceTexture safely through the listener instead of
// directly on the TextureView
mSurfaceTextureListener = new SurfaceTextureReleaseBlockingListener(mTextureView);
parent.addView(mTextureView);
}
@NonNull
@Override
public Preview.PreviewSurfaceProvider getPreviewSurfaceProvider() {
return (resolution, surfaceReleaseFuture) -> {
// Create the SurfaceTexture. Using a FixedSizeSurfaceTexture, because the
// TextureView might try to change the size of the SurfaceTexture if layout has not
// yet completed.
final SurfaceTexture surfaceTexture = new FixedSizeSurfaceTexture(0, resolution);
surfaceTexture.detachFromGLContext();
final Surface surface = new Surface(surfaceTexture);
final WindowManager windowManager =
(WindowManager) mTextureView.getContext().getSystemService(
Context.WINDOW_SERVICE);
Preconditions.checkNotNull(windowManager);
final Display display = windowManager.getDefaultDisplay();
// Setup the TextureView for the correct transformation
final Matrix matrix = transformCenterCrop(resolution, mTextureView,
display.getRotation());
mTextureView.setTransform(matrix);
final ViewGroup parent = (ViewGroup) mTextureView.getParent();
parent.removeView(mTextureView);
parent.addView(mTextureView);
// Set the SurfaceTexture safely instead of directly calling
// mTextureView.setSurfaceTexture(surfaceTexture);
mSurfaceTextureListener.setSurfaceTextureSafely(surfaceTexture, surfaceReleaseFuture);
surfaceReleaseFuture.addListener(surface::release, CameraXExecutors.directExecutor());
return Futures.immediateFuture(surface);
};
}
}