android 把activity的view转换为bitmap

 public Bitmap getActivityBitmap(Activity activity) {
// 获取windows中最顶层的view
        View view = activity.getWindow().getDecorView();
        view.buildDrawingCache();
// 获取状态栏高度
        Rect rect = new Rect();
        view.getWindowVisibleDisplayFrame(rect);
        int statusBarHeights = rect.top;
        Display display = activity.getWindowManager().getDefaultDisplay();
// 获取屏幕宽和高
        int widths = display.getWidth();
        int heights = display.getHeight();
// 允许当前窗口保存缓存信息
        view.setDrawingCacheEnabled(true);
// 去掉状态栏
        Bitmap bmp = Bitmap.createBitmap(view.getDrawingCache(), 0,
                statusBarHeights, widths, heights - statusBarHeights);
// 销毁缓存信息
        view.destroyDrawingCache();
        return bmp;
    }


 public Bitmap getViewBitmap(View  view) {
        view.setDrawingCacheEnabled(true);
        view.buildDrawingCache();  //启用DrawingCache并创建位图
        Bitmap bitmap = Bitmap.createBitmap(view.getDrawingCache()); //创建一个DrawingCache的拷贝，因为DrawingCache得到的位图在禁用后会被回收
        view.setDrawingCacheEnabled(false);  //禁用DrawingCahce否则会影响性能

        return bitmap;
    }