/** 
* 设置添加屏幕的背景透明度 
* @param bgAlpha 
*/ 
public void backgroundAlpha(float bgAlpha) 
{ 
  WindowManager.LayoutParams lp = getWindow().getAttributes(); 
  　　　　lp.alpha = bgAlpha; //0.0-1.0 
    getWindow().setAttributes(lp); 
} 

recomPopup = new RecomPopup(mContext); 
      recomPopup.setShowListener(new RecomPopup.ShowListener() { 
        @Override 
        public void show() { 
          backgroundAlpha(0.6f); 
        } 
      }); 
      recomPopup.setDismissListener(new RecomPopup.DismissListener() { 
        @Override 
        public void dismiss() { 
          backgroundAlpha(1f); 
        } 
      }); 
      recomPopup.showAtLocation(include_bottom, Gravity.NO_GRAVITY, 0, DevicesInfoUtils.getScreenHeight(mContext) - recomPopup.getHeight()); 

private ShowListener showListener; 
private DismissListener dismissListener; 
 
  @Override 
  public void showAtLocation(View parent, int gravity, int x, int y) { 
    super.showAtLocation(parent, gravity, x, y); 
    if (showListener != null){ 
      showListener.show(); 
    } 
  } 
 
  @Override 
  public void dismiss() { 
    super.dismiss(); 
    if (dismissListener != null){ 
      dismissListener.dismiss(); 
    } 
  } 
 
  public void setShowListener(ShowListener showListener) { 
    this.showListener = showListener; 
  } 
 
  public void setDismissListener(DismissListener dismissListener) { 
    this.dismissListener = dismissListener; 
  } 
 
  public interface ShowListener{ 
    void show(); 
  } 
 
  public interface DismissListener{ 
    void dismiss(); 
  }