Android中Bitmap, Drawable, Byte,ID之间的转化

Android中Bitmap, Drawable, Byte,ID之间的转化
博客分类： Android

1.  Bitmap 转化为 byte
ByteArrayOutputStream out = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
byte[] array= out.toByteArray();

2. byte转化为bitmap
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);

3. bitmap转化为Drawable
Drawable drawable = new FastBitmapDrawable(bitmap);
/ Bitmap → Drawable
public static Drawable convertBitmap2Drawable(Bitmap bitmap) {
BitmapDrawable bd = new BitmapDrawable(bitmap);
// 因为BtimapDrawable是Drawable的子类，最终直接使用bd对象即可。
return bd;
}

4. Drawable转化为bitmap
a. BitmapDrawable, FastBitmapDrawable直接用getBitmap
b. 其他类型的Drawable用Canvas画到一个bitmap上
Canvas canvas = new Canvas(bitmap)
drawable.draw(canvas)

5.id转化graphic.drawable

Drawable drawable = activity.getResources().getDrawable(R.drawable.icon);

6.id转化成Bitmap

Bitmap bitmap = BitmapFactory. decodeResource (Resources   res, int id)

转：http://xiechengfa.iteye.com/blog/1117611