A TextureView can be used to display a content stream. Such a content - * stream can for instance be a video or an OpenGL scene. The content stream + *
A TextureView can be used to display a content stream, such as that + * coming from a camera preview, a video, or an OpenGL scene. The content stream * can come from the application's process as well as a remote process.
* *TextureView can only be used in a hardware accelerated window. When @@ -43,56 +43,81 @@ import android.util.Log; * *
Unlike {@link SurfaceView}, TextureView does not create a separate
* window but behaves as a regular View. This key difference allows a
- * TextureView to be moved, transformed, animated, etc. For instance, you
- * can make a TextureView semi-translucent by calling
- * myView.setAlpha(0.5f).
myView.setAlpha(0.5f).
+ *
+ * One implication of this integration of TextureView into the view + * hierarchy is that it may have slower performance than + * SurfaceView. TextureView contents must be copied, internally, from the + * underlying surface into the view displaying those contents. For + * that reason, SurfaceView is recommended as a more general solution + * to problems requiring rendering to surfaces.
* *Using a TextureView is simple: all you need to do is get its * {@link SurfaceTexture}. The {@link SurfaceTexture} can then be used to - * render content. The following example demonstrates how to render the - * camera preview into a TextureView:
+ * render content. The following example demonstrates how to render a video + * into a TextureView: * *
- * public class LiveCameraActivity extends Activity implements TextureView.SurfaceTextureListener {
- * private Camera mCamera;
+ * public class MyActivity extends Activity implements TextureView.SurfaceTextureListener {
+ * private MediaPlayer mMediaPlayer;
* private TextureView mTextureView;
*
* protected void onCreate(Bundle savedInstanceState) {
* super.onCreate(savedInstanceState);
*
+ * mMediaPlayer = new MediaPlayer();
+ *
* mTextureView = new TextureView(this);
* mTextureView.setSurfaceTextureListener(this);
- *
* setContentView(mTextureView);
* }
*
- * public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
- * mCamera = Camera.open();
- *
- * try {
- * mCamera.setPreviewTexture(surface);
- * mCamera.startPreview();
- * } catch (IOException ioe) {
- * // Something bad happened
- * }
+ * public void onSurfaceTextureAvailable(@NonNull SurfaceTexture surfaceTexture,
+ * int width, int height) {
+ * AssetFileDescriptor fileDescriptor = // get file descriptor
+ * mMediaPlayer.setDataSource(fileDescriptor);
+ * mMediaPlayer.setSurface(new Surface(surfaceTexture));
+ * mMediaPlayer.prepareAsync();
+ * mMediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
+ * @Override
+ * public void onPrepared(MediaPlayer mp) {
+ * mMediaPlayer.start();
+ * }
+ * });
+ * } catch (IOException e) {
+ * e.printStackTrace();
+ * }
* }
*
- * public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
- * // Ignored, Camera does all the work for us
- * }
+ * @Override
+ * public void onSurfaceTextureSizeChanged(@NonNull SurfaceTexture surfaceTexture,
+ * int width, int height) {
+ * // Handle size change depending on media needs
+ * }
*
- * public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
- * mCamera.stopPreview();
- * mCamera.release();
- * return true;
- * }
+ * @Override
+ * public boolean onSurfaceTextureDestroyed(@NonNull SurfaceTexture surfaceTexture) {
+ * // Release unneeded resources
+ * mMediaPlayer.stop();
+ * mMediaPlayer.release();
+ * return true;
+ * }
+ *
+ * @Override
+ * public void onSurfaceTextureUpdated(@NonNull SurfaceTexture surfaceTexture) {
+ * // Invoked every time there's a new video frame
+ * }
*
- * public void onSurfaceTextureUpdated(SurfaceTexture surface) {
- * // Invoked every time there's a new Camera preview frame
- * }
* }
*
*
+ * Similarly, TextureView can supply the surface needed for GL rendering or + * camera previews. Camera2 APIs require the surface created by TextureView, + * although developers are recommended to use the CameraX APIs instead, for which + * PreviewView creates its own TextureView or SurfaceView internally.
+ * *A TextureView's SurfaceTexture can be obtained either by invoking * {@link #getSurfaceTexture()} or by using a {@link SurfaceTextureListener}. * It is important to know that a SurfaceTexture is available only after the