Screenshot mit OverlayService Knopf

Question

Einnahme habe ich Overlay Service button.when I Overlay klicken, genommen Snapshot wird jedoch eine Ausnahme

android.view.Window.getDecorView geworfen wird()‘auf ein Null-Objekt Referenz

-Code als

Hauptaktivität

public class MainActivity extends Activity 

    public View v2; 

    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     isStoragePermissionGranted(); 


     DisplayMetrics displaymetrics = new DisplayMetrics(); 
     getWindowManager().getDefaultDisplay().getMetrics(displaymetrics); 
     int widthContentView = displaymetrics.widthPixels; 
     int heightContentView = displaymetrics.heightPixels; 
     Log.e("dis", widthContentView + " " + heightContentView); 


     v2 = getWindow().getDecorView().getRootView(); 
     Log.e("main", v2.toString()); 
     Intent svc = new Intent(this, OverlayShowingService.class); 
     startService(svc); 
     finish(); 
    } 

    public boolean isStoragePermissionGranted() { 
     if (Build.VERSION.SDK_INT >= 23) { 
      if (checkSelfPermission(android.Manifest.permission.WRITE_EXTERNAL_STORAGE) 
        == PackageManager.PERMISSION_GRANTED) { 
       Log.v(TAG, "Permission is granted"); 
       return true; 
      } else { 

       Log.v(TAG, "Permission is revoked"); 
       ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1); 
       return false; 
      } 
     } else { //permission is automatically granted on sdk<23 upon installation 
      Log.v(TAG, "Permission is granted"); 
      return true; 
     } 
    } 

    public void takeScreenshot(View v) { 

     Date now = new Date(); 
     android.text.format.DateFormat.format("yyyy-MM-dd_hh:mm:ss", now); 

     try { 

      Log.e("line", "155"); 
      String mPath = Environment.getExternalStorageDirectory().toString() + "/" + now + ".jpg"; 
      Log.e("line", mPath); 
      MainActivity mainActivity = new MainActivity(); 
      Bitmap bitmap; 
      DisplayMetrics displaymetrics = new DisplayMetrics(); 
      int widthContentView = displaymetrics.widthPixels; 
      int heightContentView = displaymetrics.heightPixels; 
      Log.e("dis", widthContentView + " " + heightContentView); 
      View v1 = getWindow().getDecorView().getRootView(); 
      Log.e("ser", v1.toString()); 
      v1.setDrawingCacheEnabled(true); 
      bitmap = Bitmap.createBitmap(v1.getDrawingCache()); 
      v1.setDrawingCacheEnabled(false); 
      Log.e("line", "163"); 
      Log.e("line", "166"); 
      File imageFile = new File(mPath); 
      Log.e("line", "174"); 
      FileOutputStream outputStream = new FileOutputStream(imageFile); 
      Log.e("line", "176"); 
      int quality = 100; 
      bitmap.compress(Bitmap.CompressFormat.JPEG, quality, outputStream); 
      Log.e("line", "179"); 
      outputStream.flush(); 
      outputStream.close(); 


     } catch (Exception e) { 

      e.printStackTrace(); 
     } 

    } 

folgt

OverlayShowingService

public class OverlayShowingService extends Service implements OnTouchListener, OnClickListener 

    private View topLeftView; 

    private Button overlayedButton; 
    private float offsetX; 
    private float offsetY; 
    private int originalXPos; 
    private int originalYPos; 
    private boolean moving; 
    private WindowManager wm; 

    @Override 
    public IBinder onBind(Intent intent) { 
     return null; 
    } 

    @Override 
    public void onCreate() { 
     super.onCreate(); 
     wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE); 

     overlayedButton = new Button(this); 
     overlayedButton.setText("Overlay"); 

     overlayedButton.setOnTouchListener(this); 
     // overlayedButton.setAlpha(0.0f); 
     overlayedButton.setBackgroundColor(Color.BLACK); 
     // overlayedButton.setBackgroundColor(0x55fe4444); 
     overlayedButton.setOnClickListener(this); 

     WindowManager.LayoutParams params = new WindowManager.LayoutParams(WindowManager.LayoutParams.WRAP_CONTENT, WindowManager.LayoutParams.WRAP_CONTENT, WindowManager.LayoutParams.TYPE_SYSTEM_ALERT, WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL, PixelFormat.TRANSLUCENT); 
     params.gravity = Gravity.LEFT | Gravity.TOP; 
     params.x = 0; 
     params.y = 0; 
     wm.addView(overlayedButton, params); 
     topLeftView = new View(this); 
     WindowManager.LayoutParams topLeftParams = new WindowManager.LayoutParams(WindowManager.LayoutParams.WRAP_CONTENT, WindowManager.LayoutParams.WRAP_CONTENT, WindowManager.LayoutParams.TYPE_SYSTEM_ALERT, WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL, PixelFormat.TRANSLUCENT); 
     topLeftParams.gravity = Gravity.LEFT | Gravity.TOP; 
     topLeftParams.x = 0; 
     topLeftParams.y = 0; 
     topLeftParams.width = 0; 
     topLeftParams.height = 0; 
     wm.addView(topLeftView, topLeftParams); 

    } 

    @Override 
    public void onDestroy() { 
     super.onDestroy(); 
     if (overlayedButton != null) { 
      wm.removeView(overlayedButton); 
      wm.removeView(topLeftView); 
      overlayedButton = null; 
      topLeftView = null; 
     } 
    } 

    @Override 
    public boolean onTouch(View v, MotionEvent event) { 

     if (event.getAction() == MotionEvent.ACTION_DOWN) { 
      float x = event.getRawX(); 
      float y = event.getRawY(); 

      moving = false; 

      int[] location = new int[2]; 
      overlayedButton.getLocationOnScreen(location); 

      originalXPos = location[0]; 
      originalYPos = location[1]; 

      offsetX = originalXPos - x; 
      offsetY = originalYPos - y; 

     } else if (event.getAction() == MotionEvent.ACTION_MOVE) { 
      int[] topLeftLocationOnScreen = new int[2]; 
      topLeftView.getLocationOnScreen(topLeftLocationOnScreen); 

      System.out.println("topLeftY=" + topLeftLocationOnScreen[1]); 
      System.out.println("originalY=" + originalYPos); 

      float x = event.getRawX(); 
      float y = event.getRawY(); 

      WindowManager.LayoutParams params = (LayoutParams) overlayedButton.getLayoutParams(); 

      int newX = (int) (offsetX + x); 
      int newY = (int) (offsetY + y); 

      if (Math.abs(newX - originalXPos) < 1 && Math.abs(newY - originalYPos) < 1 && !moving) { 
       return false; 
      } 

      params.x = newX - (topLeftLocationOnScreen[0]); 
      params.y = newY - (topLeftLocationOnScreen[1]); 

      wm.updateViewLayout(overlayedButton, params); 
      moving = true; 
     } else if (event.getAction() == MotionEvent.ACTION_UP) { 
      if (moving) { 
       return true; 
      } 
     } 

     return false; 
    } 

    @Override 
    public void onClick(View v) { 
     Toast.makeText(this, "hai....", Toast.LENGTH_SHORT).show(); 
     MainActivity mainActivity=new MainActivity(); 
     mainActivity.takeScreenshot(v); 

    } 

I gleiche Klasse in der Aktivität verwendet habe ich diese Zeit keinen Fehler bekam. Ich drucke Ansicht com.android.internal.policy.PhoneWindow $ DecorView {f1da4b9 VE ..... R ....... 0,0-720,1212} aber in meiner Service-Klasse drucke ich Ansicht com.android.internal.policy.PhoneWindow $ DecorView {40bf076 VE ..... R ..... ID 0,0-0,0}

for ref exception

Answer 1

ich glaube, Sie vergessen um Erlaubnis hinzuzufügen.

<manifest .....> 

     <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/> 
     <application 

      .............. 
      .............> 
      <service 
        android:name=".services.OverlayShowingService" 
        android:enabled="true" 
        android:exported="false"> 

       </service> 


      </application> 
</manifest> 

Source