android 怎样用代码设立墙纸

                String imageUrl = ImageList.get(currentIndex);                String imagePath = drawableManager.getImagePath(imageUrl);                try {//                    getApplicationContext().setWallpaper(getWrapperBitmap(new BitmapDrawable(BitmapFactory.decodeFile(imagePath))));//                    getApplicationContext().setWallpaper(drawableManager.getFixBitmap(width * 2, height, imagePath));//                    Bitmap bitmap = BitmapFactory.decodeFile(imagePath);                    WallpaperManager instance = WallpaperManager.getInstance(this);                    int desiredMinimumWidth = instance.getDesiredMinimumWidth();                    int desiredMinimumHeight = instance.getDesiredMinimumHeight();                    instance.setBitmap(drawableManager.getFixBitmap(desiredMinimumWidth, desiredMinimumHeight, imagePath));                    Toast.makeText(this, "墙纸设置成功！", Toast.LENGTH_SHORT).show();                } catch (IOException e) {                    e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.                    Toast.makeText(this, "墙纸设置失败！", Toast.LENGTH_SHORT).show();                }