android bitmap drawable canvas

转换方法：1）Bitmap 转化为 byteByteArrayOutputStream out = new ByteArrayOutputStream();bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);byte[] array= out.toByteArray();2）byte转化为bitmapfinal ContentResolver contentResolver = context.getContentResolver();final PackageManager manager = context.getPackageManager();final Cursor c = contentResolver.query(uri, null, null, null, null);final int icon3DIndex = c.getColumnIndexOrThrow(ColumnName);byte[] data = c.getBlob(icon3DIndex);Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);3）bitmap 转换 drawableBitmap bitmap = new Bitmap(...); Drawable drawable = new BitmapDrawable(bitmap);//Drawable drawable = new FastBitmapDrawable(bitmap);4）Drawable to Bitmap a. BitmapDrawable, FastBitmapDrawable直接用getBitmap b. 其他类型的Drawable用Canvas画到一个bitmap上

public static Bitmap drawableToBitmap (Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable)drawable).getBitmap();
}

Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);

return bitmap;
}