Android把view的画面转换为bitmap

ImageView iv = (ImageView) findViewById(R.id.ImageView01);
ImageView iv2 = (ImageView) findViewById(R.id.ImageView02);
ImageView iv3 = (ImageView) findViewById(R.id.ImageView03);
 
//draw的方式对整屏截取，但信息栏为黑色
View cv = getWindow().getDecorView();  
Bitmap b = Bitmap.createBitmap(200, 200, Bitmap.Config.RGB_565);  
cv.draw(new Canvas(b));
iv.setImageBitmap(b);
 
//对隐藏的未画过的对象，截出的是黑色
Bitmap image = Bitmap.createBitmap(200, 200, Bitmap.Config.RGB_565);
bt3.draw(new Canvas(image));
iv2.setImageBitmap(image);
 
//get drawable cache , bitmap to drawable
bt4.setDrawingCacheEnabled(true);
Bitmap bitmap = bt4.getDrawingCache();
Drawable drawable = (Drawable) new BitmapDrawable(bitmap);
iv3.setBackgroundDrawable(drawable);