在我的代码中，我在单击按钮时进行了摄像头预览和视频录制，因此我的代码可以很好地进行录制和预览。
但是当我按下后退按钮时，在调用 surfaceview destroy 方法之后调用 surfaceview 创建和 surface view change 方法，所以我必须再次按下 back 按钮，此时它直接调用 surface destroy(第二次 surface create 和 surface change不被调用)
这是我的代码，任何人都可以帮助我吗？
public class VideoCapture extends Activity implements SurfaceHolder.Callback {
public static final String LOGTAG = "VIDEOCAPTURE";
private static final int SELECT_PHOTO = 100;
private MediaRecorder recorder;
private SurfaceHolder holder;
private CamcorderProfile camcorderProfile;
private Camera camera;
boolean recording = false;
boolean usecamera = true;
boolean previewRunning = false;
Button recorderButton,selectVideo;
long init,now,time;
Handler handler;
Runnable updater;
SimpleDateFormat df;
Camera.Parameters parameters;
String timeString, timeStamp,selectedVideoPath;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
setContentView(R.layout.main);
handler = new Handler();
df = new SimpleDateFormat("mm:ss");
camcorderProfile = CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH);
recorderButton = (Button)findViewById(R.id.button);
selectVideo = (Button)findViewById(R.id.videoselect);
final TextView timerText = (TextView)findViewById(R.id.time);
File dir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_DCIM), "/Filme");
if (!dir.exists()) {
dir.mkdirs();
}
// Animation for blinking red dot while recording
SurfaceView cameraView = (SurfaceView) findViewById(R.id.CameraView);
holder = cameraView.getHolder();
holder.addCallback(this);
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
cameraView.setClickable(true);
cameraView.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View v) {
camera.autoFocus(new AutoFocusCallback(){
@Override
public void onAutoFocus(boolean arg0, Camera arg1) {
//camera.takePicture(shutterCallback, rawCallback, jpegCallback);
}
});
}
});
selectVideo.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("video/*");
startActivityForResult(photoPickerIntent, SELECT_PHOTO);
}
});
recorderButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (recording) {
recorderButton.setBackgroundResource(R.drawable.recordbutton_background_selector);
recorder.stop();
handler.removeCallbacks(updater); // stop handler
// to refresh media scan on storage
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse
("file://" + Environment.getExternalStorageDirectory())));
String filepath =Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM)+File.separator+"Filme"+File.separator+"Filme_"+timeStamp+".mp4";
Intent i = new Intent(getBaseContext(),VideoCutActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.putExtra("path", filepath);
getBaseContext().startActivity(i);
finish();
/*
if (usecamera) {
try {
camera.reconnect();
} catch (IOException e) {
e.printStackTrace();
}
}
*/
recording = false;
Log.v(LOGTAG, "Recording Stopped");
// Let's prepareRecorder so we can record again
// prepareRecorder();
} else {
recorderButton.setBackgroundResource(R.drawable.stopbutton_background_selector);
recording = true;
prepareRecorder();
// recorder.start();
Log.v(LOGTAG, "Recording Started");
}
}
});
// Recording timmer
updater = new Runnable() {
@Override
public void run() {
now=System.currentTimeMillis();
time=now-init;
timeString = df.format(new Date(time));
timerText.setText(timeString);
handler.postDelayed(this, 30);
}
};
}
@Override
protected void onResume() {
super.onResume();
Log.e("onresume", "on resume");
// Open the default i.e. the first rear facing camera.
}
@Override
protected void onPause() {
super.onPause();
// Because the Camera object is a shared resource, it's very
// important to release it when the activity is paused.
if (recording) {
recorder.stop();
recording = false;
recorder.release();
camera.stopPreview();
camera.setPreviewCallback(null);
camera.release();
camera = null;
}
else
{
if (camera != null) {
previewRunning = false;
camera.release();
camera = null;
}
}}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent imageReturnedIntent) {
super.onActivityResult(requestCode, resultCode, imageReturnedIntent);
switch(requestCode) {
case SELECT_PHOTO:
if(resultCode == RESULT_OK){
Uri selectedImage = imageReturnedIntent.getData();
selectedVideoPath = getPath(selectedImage);
Intent i = new Intent(getBaseContext(),VideoCutActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.putExtra("path", selectedVideoPath);
VideoCapture.this.startActivity(i);
finish();
}
}
}
public String getPath(Uri uri) {
String[] proj = { MediaStore.Images.Media.DATA };
CursorLoader loader = new CursorLoader(getBaseContext(), uri, proj, null, null, null);
Cursor cursor = loader.loadInBackground();
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
private void prepareRecorder() {
recorder = new MediaRecorder();
recorder.setPreviewDisplay(holder.getSurface());
if (usecamera) {
camera.unlock();
recorder.setCamera(camera);
}
recorder.setAudioSource(MediaRecorder.AudioSource.DEFAULT);
recorder.setVideoSource(MediaRecorder.VideoSource.DEFAULT);
recorder.setProfile(camcorderProfile);
timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
recorder.setOutputFile(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM)+File.separator+"Filme"+File.separator+"Filme_"+timeStamp+".mp4");
Log.v(LOGTAG, "camcorderProfile");
try {
recorder.prepare();
recorder.start();
init = System.currentTimeMillis();
handler.post(updater);
} catch (IllegalStateException e) {
e.printStackTrace();
finish();
} catch (IOException e) {
e.printStackTrace();
finish();
}
}
public void surfaceCreated(SurfaceHolder holder) {
Log.v(LOGTAG, "surfaceCreated");
if (usecamera) {
camera = Camera.open();
parameters = camera.getParameters();
try {
Log.i("Capture","surface created");
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
camera.setParameters(parameters);
camera.setPreviewDisplay(holder);
camera.startPreview();
previewRunning = true;
}
catch (IOException e) {
Log.e(LOGTAG,e.getMessage());
e.printStackTrace();
}
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Log.v(LOGTAG, "surfaceChanged");
if (!recording && usecamera) {
if (previewRunning){
Log.e("Capture","preview is running");
camera.stopPreview();
}
try {
Log.e("Capture","inside try of surface changed");
parameters = camera.getParameters();
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
parameters.setPreviewSize(camcorderProfile.videoFrameWidth, camcorderProfile.videoFrameHeight);
parameters.setPreviewFrameRate(camcorderProfile.videoFrameRate);
camera.setParameters(parameters);
camera.setPreviewDisplay(holder);
camera.startPreview();
previewRunning = true;
}
catch (IOException e) {
Log.e(LOGTAG,e.getMessage());
e.printStackTrace();
}
// prepareRecorder();
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
Log.v(LOGTAG, "surfaceDestroyed");
if (camera != null) {
camera.stopPreview();
}
if (recording) {
try{
Log.e("Capture","inside recording of surface destory");
recorder.stop();
recording = false;
recorder.release();
camera.stopPreview();
camera.setPreviewCallback(null);
camera.release();
camera = null;
}
catch (RuntimeException e) {
Log.d("surface destroyed", "Problem in surfaceDestroyed");
e.printStackTrace();
}
}
最佳答案
基于调试/聊天讨论:
第一次返回时，现有的 Camera Activity 被销毁并创建了另一个。使用以下内容跟踪返回堆栈中的更改:
adb shell dumpsys Activity | grep -i 运行
不需要新的任务，所以这是无用的: i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
显然，使用 i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP) 有帮助!
但我不确定为什么这会有所帮助。 (特别是，因为 IIUC，使用 *CLEAR_TOP，将使用堆栈上 Activity 的现有实例(使用 onNewIntent)，但在这里(根据 dumpsys 的输出，创建了一个新 Activity :|)。但它适用于爱可视。
关于当我在 jellybean 上的 archos 平板电脑上按下后退按钮时，Android Camera 表面 View 相机重新创建，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/19629591/