我正在尝试编写适用于相机的Android应用程序。 我在textureview中显示了相机的预览，这是有效的。如果按一个按钮，相机将拍摄照片并将其显示在屏幕后半部分的图像视图中。 但每次我按下按钮我的应用程序停止工作，它告诉我错误
android.view.ViewRootImpl $ CalledFromWrongThreadException：只有 创建视图层次结构的原始线程可以触及其视图。
所以我查了一下，似乎在我尝试时我无法改变imageview的图像。但我不知道如何解决我的问题。你能给我一些建议吗？这是我的代码：图像在＆＃34; ImageReader.OnImageAvailableListener＆＃34;中更改。在方法takePicture（）。
public class MainActivityOld extends Activity {
private TextureView mTextureView;
private ImageView mImageView;
private CameraDevice mCameraDevice;
private Size mPreviewSize;
private CaptureRequest.Builder mPreviewBuilder;
private CameraCaptureSession mPreviewSession;
private Button mBtnShot;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//no titlebar
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
mTextureView = (TextureView) findViewById(R.id.texture);
mTextureView.setSurfaceTextureListener(mSurfaceListener);
mImageView = (ImageView) findViewById(R.id.lastPicture);
mBtnShot = (Button) findViewById(R.id.btn_takepicture);
mBtnShot.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
takePicture();
}
});
}
private void takePicture() {
Log.e("MyTag", "Take picture");
CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
try {
CameraCharacteristics characteristics = manager.getCameraCharacteristics(mCameraDevice.getId());
Size[] jpegSizes = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP).getOutputSizes(ImageFormat.JPEG);
int width = jpegSizes[0].getWidth();
int height = jpegSizes[0].getHeight();
ImageReader reader = ImageReader.newInstance(width, height, ImageFormat.JPEG, 1);
List<Surface> outputSurfaces = new ArrayList<Surface>(2);
outputSurfaces.add(reader.getSurface());
outputSurfaces.add(new Surface(mTextureView.getSurfaceTexture()));
final CaptureRequest.Builder captureBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(reader.getSurface());
captureBuilder.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO);
ImageReader.OnImageAvailableListener readerListener = new ImageReader.OnImageAvailableListener(){
@Override
public void onImageAvailable(ImageReader reader) {
Image image = reader.acquireLatestImage();
ByteBuffer buffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.capacity()];
buffer.get(bytes);
Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
mImageView.setImageBitmap(bitmap);
}
};
HandlerThread thread = new HandlerThread("CameraPicture");
thread.start();
final Handler backgroundHandler = new Handler(thread.getLooper());
reader.setOnImageAvailableListener(readerListener,backgroundHandler);
final CameraCaptureSession.CaptureCallback captureListener = new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, TotalCaptureResult result) {
super.onCaptureCompleted(session, request, result);
startPreview();
}
};
mCameraDevice.createCaptureSession(outputSurfaces, new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(CameraCaptureSession session) {
try {
session.capture(captureBuilder.build(), captureListener, backgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onConfigureFailed(CameraCaptureSession session) {
}
}, backgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void openCamera() {
CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
try {
String cameraId = manager.getCameraIdList()[0];
CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId);
StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
mPreviewSize = map.getOutputSizes(SurfaceTexture.class)[0];
manager.openCamera(cameraId, mStateCallback, null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
Log.e("MyTag", "openCamera");
}
private TextureView.SurfaceTextureListener mSurfaceListener = new TextureView.SurfaceTextureListener() {
@Override
public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
Log.e("myLog", "onSurfaceTextureAvailable, width=" + width + ",height=" + height);
openCamera();
}
@Override
public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
}
@Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
return false;
}
@Override
public void onSurfaceTextureUpdated(SurfaceTexture surface) {
}
};
private CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() {
@Override
public void onOpened(CameraDevice camera) {
Log.e("myTag", "onOpened");
mCameraDevice = camera;
startPreview();
}
@Override
public void onDisconnected(CameraDevice camera) {
Log.e("myTag", "onDisconnected");
}
@Override
public void onError(CameraDevice camera, int error) {
Log.e("myTag", "onDisconnected");
}
};
protected void startPreview() {
if (mCameraDevice == null || mTextureView.isAvailable() || mPreviewSize == null) {
Log.e("MyTag", "startPreview failed, still working, so just ignore it");
// return;
}
SurfaceTexture texture = mTextureView.getSurfaceTexture();
texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());
Surface surface = new Surface(texture);
try {
mPreviewBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
} catch (CameraAccessException e) {
e.printStackTrace();
}
mPreviewBuilder.addTarget(surface);
try {
mCameraDevice.createCaptureSession(Arrays.asList(surface), new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(CameraCaptureSession session) {
mPreviewSession = session;
updatePreview();
}
@Override
public void onConfigureFailed(CameraCaptureSession session) {
Toast.makeText(MainActivityOld.this, "onConfigureFailed", Toast.LENGTH_LONG).show();
}
}, null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
protected void updatePreview() {
mPreviewBuilder.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO);
HandlerThread thread = new HandlerThread("CameraPreview");
thread.start();
Handler backgroundHandler = new Handler(thread.getLooper());
try {
mPreviewSession.setRepeatingRequest(mPreviewBuilder.build(), null, backgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
}
答案 0 :(得分：2)
正如100644 b16bd8d4e57de7705a5a388d045fed7376a1b175 1 MyProject.userprefs
100644 ef238f895ca1b80f10cfcd45349d82df925ff482 3 MyProject.userprefs
说Exception，您的CalledFromWrongThreadException正在处理另一个主题，您无法更改自己的观点。
将您的代码更改为：
readerListener答案 1 :(得分：1)