当我在jellybean上的archos平板上按后退按钮时，Android相机的表面视图重新创建了。

Question

在我的代码中，我有相机预览和视频录制按钮点击，所以我的代码很好地记录和预览。

但是当我按下后退按钮时，就会在表面视图破坏方法调用之后调用表面视图创建和表面视图更改方法，所以我不得不再次按下后退按钮，此时它直接调用曲面破坏(第二次曲面创建和曲面更改没有调用)。

这是我的密码有人能帮我吗？

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();
            } 
        }

Answer 1

基于对聊天的调试/讨论：

• 第一次回击时，现有的相机活动被破坏，另一个被创建。使用以下方法跟踪后台堆栈中的更改： 亚洲开发银行shell虚拟活动\ 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)是有帮助的！

我不知道这到底有什么用。(特别是，由于IIUC，对于*CLEAR_TOP，堆栈上的活动的现有实例将被使用(与onNewIntent一起使用)，但是在这里(根据来自虚拟库的输出，将创建一个新的活动:x)。但它适用于archos。