Android realizes the function of silently taking pictures by opening the service in the background

In this paper, we share the specific code of Android background opening service silently for your reference. The specific contents are as follows

Recent project reasons, need to write 1 background running procedures, in a given time interval to take photos, the key technologies are: 1, open the service; 2. Take pictures without previewing. 3. Use AlarmManager for timing operation.

The list of resources is as follows:

<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
 package="com.yang.testservice" 
 android:versionCode="1" 
 android:versionName="1.0" > 
 
 <uses-feature android:name="android.hardware.camera" /> 
 <uses-feature android:name="android.hardware.camera.autofocus" /> 
 
 <uses-permission android:name="android.permission.CAMERA" /> 
 <uses-permission android:name="android.permission.FLASHLIGHT" /> 
 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 
 
 <uses-feature android:name="android.hardware.camera.any" /> 
 
 <uses-sdk 
  android:minSdkVersion="13" 
  android:targetSdkVersion="15" /> 
 
 <application 
  android:icon="@drawable/ic_launcher" 
  android:label="@string/app_name" 
  android:theme="@style/AppTheme" > 
  <activity 
   android:name=".MainActivity" 
   android:label="@string/title_activity_main" > 
   <intent-filter> 
    <action android:name="android.intent.action.MAIN" /> 
 
    <category android:name="android.intent.category.LAUNCHER" /> 
   </intent-filter> 
  </activity> 
 
  <service android:name="com.yang.service.LocalService" /> 
 </application> 
 
</manifest> 

The service code is as follows:

package com.yang.service; 
 
import java.io.IOException; 
 
import android.app.AlarmManager; 
import android.app.Notification; 
import android.app.NotificationManager; 
import android.app.PendingIntent; 
import android.app.Service; 
import android.content.BroadcastReceiver; 
import android.content.Context; 
import android.content.Intent; 
import android.content.IntentFilter; 
import android.hardware.Camera; 
import android.os.Binder; 
import android.os.IBinder; 
import android.util.Log; 
import android.view.SurfaceView; 
import android.widget.Toast; 
 
import com.yang.handle.PhotoHandler; 
import com.yang.testservice.MainActivity; 
import com.yang.testservice.R; 
 
public class LocalService extends Service { 
 
 private AlarmManager am = null; 
 private Camera camera; 
 
 private final IBinder mBinder = new LocalBinder(); 
 
 private NotificationManager mNM; 
 
 private int NOTIFICATION = R.string.local_service_started; 
 
 /** 
  * Class for clients to access. Because we know this service always runs in 
  * the same process as its clients, we don't need to deal with IPC. 
  */ 
 public class LocalBinder extends Binder { 
  public LocalService getService() { 
   return LocalService.this; 
  } 
 
 } 
 
 @Override 
 public void onCreate() { 
  mNM = (NotificationManager) getSystemService(NOTIFICATION_SERVICE); 
  showNotification(); 
  init(); 
 } 
 
 private void init() { 
  am = (AlarmManager) getSystemService(ALARM_SERVICE); 
 
  camera = openFacingBackCamera(); 
 
  //  Registered broadcast  
  IntentFilter filter = new IntentFilter(); 
  filter.addAction("com.vegetables_source.alarm"); 
  registerReceiver(alarmReceiver, filter); 
 
  Intent intent = new Intent(); 
  intent.setAction("com.vegetables_source.alarm"); 
  PendingIntent pi = PendingIntent.getBroadcast(this, 0, intent, 0); 
 
  am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), 
    1000 * 10, pi);//  Start right away, every 1 Minute trigger 1 Times  
 } 
 
 @Override 
 public int onStartCommand(Intent intent, int flags, int startId) { 
  Log.i("LocalService", "Received start id " + startId + ": " + intent); 
 
  return START_STICKY; 
 } 
 
 @Override 
 public void onDestroy() { 
  mNM.cancel(NOTIFICATION); 
 
  cancelAlertManager(); 
 
  if (camera != null) { 
   camera.release(); 
   camera = null; 
  } 
 
  Toast.makeText(this, R.string.local_service_stopped, Toast.LENGTH_SHORT) 
    .show(); 
 } 
 
 @Override 
 public IBinder onBind(Intent intent) { 
  return mBinder; 
 } 
 
 /** 
  * Show a notification while this service is running. 
  */ 
 private void showNotification() { 
  CharSequence text = getText(R.string.local_service_started); 
 
  Notification notification = new Notification(R.drawable.stat_running, 
    text, System.currentTimeMillis()); 
 
  PendingIntent contentIntent = PendingIntent.getActivity(this, 0, 
    new Intent(this, MainActivity.class), 0); 
 
  notification.setLatestEventInfo(this, 
    getText(R.string.local_service_label), text, contentIntent); 
 
  mNM.notify(NOTIFICATION, notification); 
 } 
 
 private void cancelAlertManager() { 
  Intent intent = new Intent(); 
  intent.setAction("com.vegetables_source.alarm"); 
  PendingIntent pi = PendingIntent.getBroadcast(this, 0, intent, 0); 
  am.cancel(pi); 
 
  //  Cancel a broadcast  
  unregisterReceiver(alarmReceiver); 
 } 
 
 BroadcastReceiver alarmReceiver = new BroadcastReceiver() { 
 
  @Override 
  public void onReceive(Context context, Intent intent) { 
   if ("com.vegetables_source.alarm".equals(intent.getAction())) { 
 
    if (camera != null) { 
     SurfaceView dummy = new SurfaceView(getBaseContext()); 
     try { 
      camera.setPreviewDisplay(dummy.getHolder()); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
     camera.startPreview(); 
 
     camera.takePicture(null, null, new PhotoHandler( 
       getApplicationContext())); 
    } 
 
   } 
 
  } 
 }; 
 
 private Camera openFacingBackCamera() { 
  Camera cam = null; 
  Camera.CameraInfo cameraInfo = new Camera.CameraInfo(); 
  ; 
  for (int camIdx = 0, cameraCount = Camera.getNumberOfCameras(); camIdx < cameraCount; camIdx++) { 
   Camera.getCameraInfo(camIdx, cameraInfo); 
   if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) { 
    try { 
     cam = Camera.open(camIdx); 
    } catch (RuntimeException e) { 
     e.printStackTrace(); 
    } 
   } 
  } 
 
  return cam; 
 } 
} 

The operation code for photo storage is as follows:

package com.yang.handle; 
 
import java.io.File; 
import java.io.FileOutputStream; 
import java.text.SimpleDateFormat; 
import java.util.Date; 
 
import android.content.Context; 
import android.hardware.Camera; 
import android.hardware.Camera.PictureCallback; 
import android.os.Environment; 
import android.widget.Toast; 
 
public class PhotoHandler implements PictureCallback { 
 
 private final Context context; 
 
 public PhotoHandler(Context context) { 
  this.context = context; 
 } 
 
 @Override 
 public void onPictureTaken(byte[] data, Camera camera) { 
 
  File pictureFileDir = getDir(); 
 
  if (!pictureFileDir.exists() && !pictureFileDir.mkdirs()) { 
 
   Toast.makeText(context, "Can't create directory to save image.", 
     Toast.LENGTH_LONG).show(); 
   return; 
 
  } 
 
  SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss"); 
  String date = dateFormat.format(new Date()); 
  String photoFile = "Picture_" + date + ".jpg"; 
 
  String filename = pictureFileDir.getPath() + File.separator + photoFile; 
 
  File pictureFile = new File(filename); 
  System.out.println("filename is "+ filename); 
 
  try { 
   FileOutputStream fos = new FileOutputStream(pictureFile); 
   fos.write(data); 
   fos.close(); 
   Toast.makeText(context, "New Image saved:" + photoFile, 
     Toast.LENGTH_LONG).show(); 
  } catch (Exception error) { 
   Toast.makeText(context, "Image could not be saved.", 
     Toast.LENGTH_LONG).show(); 
  } 
 } 
 
 private File getDir() { 
  File sdDir = Environment 
   .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES); 
  return new File(sdDir, "ServiceCamera"); 
 } 
} 

The project code is as follows:

Android background open service silently take pictures