嗨，我在我的android项目中使用camera 2 api，我关注了这个项目 https://github.com/pinhassi/android-Camera2Basic.git 在哪里使用相机捕获图像并将其保存在存储器中。
我想做的是
在takePicture上，我想停止相机预览并显示捕获的图像。我该怎么做。
应如何安排回调以在takePicture上停止预览。
谢谢 R
@Override
public void onResume() {
super.onResume();
startBackgroundThread();
// When the screen is turned off and turned back on, the SurfaceTexture is already
// available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open
// a camera and start preview from here (otherwise, we wait until the surface is ready in
// the SurfaceTextureListener).
if (mTextureView.isAvailable()) {
openCamera(mTextureView.getWidth(), mTextureView.getHeight());
} else {
mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);
}
if(null != takenPictureBytes && takenPictureBytes.length > 0){
switchPanels(true);
}else{
switchPanels(false);
}
}
private final TextureView.SurfaceTextureListener mSurfaceTextureListener
= new TextureView.SurfaceTextureListener() {
@Override
public void onSurfaceTextureAvailable(SurfaceTexture texture, int width, int height) {
openCamera(width, height);
}
@Override
public void onSurfaceTextureSizeChanged(SurfaceTexture texture, int width, int height) {
configureTransform(width, height);
}
@Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture texture) {
return true;
}
@Override
public void onSurfaceTextureUpdated(SurfaceTexture texture) {
}
};
private void openCamera(int width, int height) {
if (ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.CAMERA)
!= PackageManager.PERMISSION_GRANTED) {
requestCameraPermission();
return;
}
setUpCameraOutputs(width, height);
configureTransform(width, height);
Activity activity = getActivity();
CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE);
try {
if (!mCameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) {
throw new RuntimeException("Time out waiting to lock camera opening.");
}
manager.openCamera(mCameraId, mStateCallback, mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
} catch (InterruptedException e) {
throw new RuntimeException("Interrupted while trying to lock camera opening.", e);
}
}
@OnClick(R.id.take_picture_button)
public void takePictureClick() {
takePictureButton.setEnabled(false);
EventsTracker.photoCaptureClicked(getContext());
EventsTracker.photoCaptureClicked(getContext());
Log.d(TAG, "take picture clicked");
progress.setVisibility(View.VISIBLE);
stopMultipleClicks();
takePicture();
}
private void takePicture() {
lockFocus();
}
private void lockFocus() {
try {
// This is how to tell the camera to lock focus.
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, CameraMetadata.CONTROL_AF_TRIGGER_START);
CaptureRequest captureRequest = mPreviewRequestBuilder.build();
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, null); // prevent CONTROL_AF_TRIGGER_START from calling over and over again
mState = STATE_WAITING_LOCK;
mCaptureSession.capture(captureRequest, mCaptureCallback, mBackgroundHandler);
// Tell #mCaptureCallback to wait for the lock.
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void unlockFocus() {
try {
// Reset the auto-focus trigger
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_TRIGGER_CANCEL);
setAutoFlash(mPreviewRequestBuilder);
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mBackgroundHandler);
// After this, the camera will go back to the normal state of preview.
mState = STATE_PREVIEW;
mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void runPrecaptureSequence() {
try {
// This is how to tell the camera to trigger.
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER,
CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_START);
// Tell #mCaptureCallback to wait for the precapture sequence to be set.
mState = STATE_WAITING_PRECAPTURE;
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private CameraCaptureSession.CaptureCallback mCaptureCallback
= new CameraCaptureSession.CaptureCallback() {
private void process(CaptureResult result) {
switch (mState) {
case STATE_PREVIEW: {
// We have nothing to do when the camera preview is working normally.
// TODO: handle auto focus
Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
if (afState != null && !afState.equals(mLastAfState)) {
switch (afState) {
case CaptureResult.CONTROL_AF_STATE_INACTIVE:
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_INACTIVE");
lockAutoFocus();
break;
case CaptureResult.CONTROL_AF_STATE_ACTIVE_SCAN:
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_ACTIVE_SCAN");
break;
case CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED:
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED");
mUiHandler.removeCallbacks(mLockAutoFocusRunnable);
mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_FOCUSED);
break;
case CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED:
mUiHandler.removeCallbacks(mLockAutoFocusRunnable);
mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_UNFOCUSED);
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED");
break;
case CaptureResult.CONTROL_AF_STATE_PASSIVE_UNFOCUSED:
mUiHandler.removeCallbacks(mLockAutoFocusRunnable);
//mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_UNFOCUSED);
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_PASSIVE_UNFOCUSED");
break;
case CaptureResult.CONTROL_AF_STATE_PASSIVE_SCAN:
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_PASSIVE_SCAN");
break;
case CaptureResult.CONTROL_AF_STATE_PASSIVE_FOCUSED:
mUiHandler.removeCallbacks(mLockAutoFocusRunnable);
//mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_FOCUSED);
Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_PASSIVE_FOCUSED");
break;
}
}
mLastAfState = afState;
break;
}
case STATE_WAITING_LOCK: {
Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
if (afState == null) {
captureStillPicture();
} else if (CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState ||
//CaptureResult.CONTROL_AF_STATE_PASSIVE_FOCUSED == afState || CaptureResult.CONTROL_AF_STATE_PASSIVE_UNFOCUSED == afState ||
CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) {
mState = STATE_PICTURE_TAKEN;
captureStillPicture();
} else {
runPrecaptureSequence();
}
}
break;
}
case STATE_WAITING_PRECAPTURE: {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE ||
aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED) {
mState = STATE_WAITING_NON_PRECAPTURE;
}
break;
}
case STATE_WAITING_NON_PRECAPTURE: {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) {
mState = STATE_PICTURE_TAKEN;
captureStillPicture();
}
break;
}
}
}
private void captureStillPicture() {
try {
final Activity activity = getActivity();
if (null == activity || null == mCameraDevice) {
return;
}
// This is the CaptureRequest.Builder that we use to take a picture.
final CaptureRequest.Builder captureBuilder =
mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(mImageReader.getSurface());
// Use the same AE and AF modes as the preview.
if (isAutoFocusSupported())
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_AUTO);
else
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
setAutoFlash(captureBuilder);
// Orientation
int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, getOrientation(rotation));
CameraCaptureSession.CaptureCallback CaptureCallback
= new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(@NonNull CameraCaptureSession session,
@NonNull CaptureRequest request,
@NonNull TotalCaptureResult result) {
Log.d(TAG, "takePicture - camera capture session");
switchPanels(true);
unlockFocus();
progress.setVisibility(View.GONE);
}
};
mCaptureSession.stopRepeating();
mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onCaptureProgressed(@NonNull CameraCaptureSession session,
@NonNull CaptureRequest request,
@NonNull CaptureResult partialResult) {
process(partialResult);
}
@Override
public void onCaptureCompleted(@NonNull CameraCaptureSession session,
@NonNull CaptureRequest request,
@NonNull TotalCaptureResult result) {
//process(result);
switchPanels(true);
unlockFocus();
progress.setVisibility(View.GONE);
}
};