ScheduledExecutorService chỉ chạy một lần bên trong Dịch vụ

Question

Tôi đang chạy ScheduledExecutorService bên trong dịch vụ của tôi có hình ảnh ở chế độ nền. ScheduledExecutorService chỉ chạy một lần có nghĩa là chỉ chụp một ảnh sau khi khoảng thời gian được truyền trong hàm. Không hiển thị lỗi nào cả. Sau đây là mã của tôi Service

package com.anawaz.spy; 

import java.io.File; 
import java.io.FileNotFoundException; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.util.concurrent.Executors; 
import java.util.concurrent.ScheduledExecutorService; 
import java.util.concurrent.ScheduledFuture; 
import java.util.concurrent.TimeUnit; 

import android.app.Service; 
import android.content.Intent; 
import android.hardware.Camera; 
import android.hardware.Camera.PictureCallback; 
import android.hardware.Camera.ShutterCallback; 
import android.os.IBinder; 
import android.util.Log; 

public class CamService extends Service { 

    private static final String TAG = "TAG"; 

    private final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1); 

    Camera camera; 
    ScheduledFuture beeperHandle; 

    /* Service Life cycle Overrides */ 
    @Override 
    public void onCreate() { 
     super.onCreate(); 
     camera = Camera.open(); 
     try { 
      camera.setPreviewDisplay(null); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
     //takePicsPeriodically(MainActivity.getSpInt(MainActivity.SP_Period)); 
     takePicsPeriodically(5); 
    } 

    @Override 
    public void onDestroy() { 
     stopPics(); 
     super.onDestroy(); 
    } 

    @Override 
    public IBinder onBind(Intent intent) { 
     // TODO Auto-generated method stub 
     return null; 
    } 

    // @Override 
    // public IBinder onBind(Intent arg0) { 
    // return myRemoteServiceStub; 
    // } 
    // /* ----------------------------------- */ 
    // 
    // private IMyRemoteService.Stub myRemoteServiceStub = new 
    // IMyRemoteService.Stub() { 
    // 
    // /* Basic Service Methods */ 
    // public boolean isCollecting() { 
    // return (beeperHandle != null); 
    // } 
    // /* ------------------------- */ 
    // }; 

    public void takePicsPeriodically(long period) { 
     final Runnable beeper = new Runnable() { 
      public void run() { 
       Log.d("TAG", "New Picture Taken"); 
       camera.takePicture(shutterCallback, rawCallback, jpegCallback); 
      } 
     }; 
     camera.startPreview(); 
     beeperHandle = scheduler.scheduleAtFixedRate(beeper, period, period,TimeUnit.SECONDS); 
    } 

    public void stopPics() { 
     beeperHandle.cancel(true); 
     beeperHandle = null; 
     camera.stopPreview(); 
     camera.release(); 
     camera = null; 
    } 

    /* Camera Call backs */ 
    ShutterCallback shutterCallback = new ShutterCallback() { 
     public void onShutter() { 
      Log.d(TAG, "onShutter'd"); 
     } 
    }; 

    /** Handles data for raw picture */ 
    PictureCallback rawCallback = new PictureCallback() { 
     public void onPictureTaken(byte[] data, Camera camera) { 
      Log.d(TAG, "onPictureTaken - raw"); 
     } 
    }; 

    /** Handles data for j peg picture */ 
    PictureCallback jpegCallback = new PictureCallback() { 
     public void onPictureTaken(byte[] data, Camera camera) { 
      FileOutputStream outStream = null; 
      try { 
       // write to local sand box file system 
       // outStream = 
       // CameraDemo.this.openFileOutput(String.format("%d.jpg", 
       // System.currentTimeMillis()), 0); 
       // Or write to s d card 
       File mFolder; 
       mFolder = new File("/sdcard/Spy/"); 
       if (!mFolder.exists()) { 
        mFolder.mkdir(); 
       } 
       outStream = new FileOutputStream(String.format(
         "/sdcard/Spy/Image_%d.jpg", System.currentTimeMillis())); 
       outStream.write(data); 
       outStream.close(); 
       Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length); 
      } catch (FileNotFoundException e) { 
       e.printStackTrace(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } finally { 
      } 
      Log.d(TAG, "onPictureTaken - jpeg"); 
     } 
    }; 

} 

Không có Logcat vì không nhận được bất kỳ lỗi nào. Dịch vụ cũng chạy sau khi chụp ảnh. Tôi đang làm gì sai?

Answer 1

Sau khi đọc bài đăng này http://code.nomad-labs.com/2011/12/09/mother-fk-the-scheduledexecutorservice/ Tôi đã thử khối try catch. Và thấy rằng camera.takePicture(shutterCallback, rawCallback, jpegCallback); đã ném ngoại lệ. Đó là vì sai lầm của tôi Tôi không bắt đầu xem trước sau khi chụp ảnh đầu tiên. Tham khảo câu trả lời này. https://stackoverflow.com/a/21728454/1770916

Sau đây là mã Làm việc được cập nhật của dịch vụ của tôi.

package com.anawaz.spy; 

import java.io.File; 
import java.io.FileNotFoundException; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.util.concurrent.Executors; 
import java.util.concurrent.ScheduledExecutorService; 
import java.util.concurrent.ScheduledFuture; 
import java.util.concurrent.TimeUnit; 

import android.app.Service; 
import android.content.Intent; 
import android.hardware.Camera; 
import android.hardware.Camera.PictureCallback; 
import android.hardware.Camera.ShutterCallback; 
import android.os.IBinder; 
import android.util.Log; 

public class CamService extends Service { 

    private static final String TAG = "TAG"; 

    private final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1); 

    Camera camera; 
    ScheduledFuture beeperHandle; 

    /* Service Life cycle Overrides */ 
    @Override 
    public void onCreate() { 
     super.onCreate(); 
     camera = Camera.open(); 
     try { 
      camera.setPreviewDisplay(null); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
     File mFolder = new File("/sdcard/Spy/"); 
     if (!mFolder.exists()) { 
      mFolder.mkdir(); 
     } 
     takePicsPeriodically(MainActivity.getSpInt(MainActivity.SP_Period)); 
     //takePicsPeriodically(5); 
    } 

    @Override 
    public void onDestroy() { 
     stopPics(); 
     super.onDestroy(); 
    } 

    @Override 
    public IBinder onBind(Intent intent) { 
     // TODO Auto-generated method stub 
     return null; 
    } 

    public void takePicsPeriodically(long period) { 
     camera.startPreview(); 
     beeperHandle = scheduler.scheduleAtFixedRate(beeper,period, period,TimeUnit.SECONDS); 
    } 

    final Runnable beeper = new Runnable() { 
     public void run() { 
      Log.d("TAG", "New Picture Taken"); 
      try { 
       camera.startPreview(); 
       camera.takePicture(shutterCallback, rawCallback, jpegCallback); 
      }catch (Exception e) { 
       Log.e("TAG","error in executing: It will no longer be run!: "+e.getMessage()); 
       e.printStackTrace(); 
      } 
     } 
    }; 
    public void stopPics() { 
     beeperHandle.cancel(true); 
     beeperHandle = null; 
     camera.stopPreview(); 
     camera.release(); 
     camera = null; 
    } 

    /* Camera Call backs */ 
    final ShutterCallback shutterCallback = new ShutterCallback() { 
     public void onShutter() { 
      Log.d(TAG, "onShutter'd"); 
     } 
    }; 

    /** Handles data for raw picture */ 
    final PictureCallback rawCallback = new PictureCallback() { 
     public void onPictureTaken(byte[] data, Camera camera) { 
      Log.d(TAG, "onPictureTaken - raw"); 
     } 
    }; 

    /** Handles data for j peg picture */ 
    final PictureCallback jpegCallback = new PictureCallback() { 
     public void onPictureTaken(byte[] data, Camera camera) { 
      FileOutputStream outStream = null; 
      try { 
       // write to local sand box file system 
       // outStream = 
       // CameraDemo.this.openFileOutput(String.format("%d.jpg", 
       // System.currentTimeMillis()), 0); 
       // Or write to s d card 

       outStream = new FileOutputStream(String.format(
         "/sdcard/Spy/Image_%d.jpg", System.currentTimeMillis())); 
       outStream.write(data); 
       outStream.close(); 
       Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length); 
      } catch (FileNotFoundException e) { 
       e.printStackTrace(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } finally { 
      } 
      Log.d(TAG, "onPictureTaken - jpeg"); 
     } 
    }; 

}