在android中单击一个活动的屏幕截图

Question

我想截取一个活动的屏幕截图并在按钮单击的下一个活动中显示它。 我正在使用下面的代码，但它不工作。
请让我知道，如果有人知道了答案：

choose.setOnClickListener(new View.OnClickListener() { 
       public void onClick(View v) { 
        mainlayout.setDrawingCacheEnabled(true); 
        mainlayout.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED), 
          View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED)); 
        mainlayout.layout(0, 0, mainlayout.getMeasuredWidth(), mainlayout.getMeasuredHeight()); 
        mainlayout.buildDrawingCache(true); 
        Bitmap b = Bitmap.createBitmap(mainlayout.getDrawingCache()); 
        mainlayout.setDrawingCacheEnabled(false); // clear drawing cache 
        Intent i4=new Intent(Screen3.this,Screen4.class); 
        i4.putExtra("BitmapImage", b); 
        startActivity(i4); 
       }//onclick 
      }); 

Answer 1

public static Bitmap captureScreen(View v){ 

     Bitmap bitmap = null; 

     try { 
      if(v!=null) 
      { 
       int width = v.getWidth(); 
       int height = v.getHeight(); 

       Bitmap screenshot = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565); 
       v.draw(new Canvas(screenshot)); 
       } 
      } 
     catch (Exception e){ 

      Log.d("captureScreen", "Failed"); 
     } 

    return bitmap; 
    } 

v是什么被捕获（任何布局）