Drawable和Bitmap转换

一、Bitmap转Drawable


Bitmap bm=xxx; //xxx根据你的情况获取

BitmapDrawable bd=new BitmapDrawable(bm);
因为BtimapDrawable是Drawable的子类，最终直接使用bd对象即可。

二、 Drawable转Bitmap

转成Bitmap对象后，可以将Drawable对象通过Android的SK库存成一个字节输出流，最终还可以保存成为jpg和png的文件。
Drawable d=xxx; //xxx根据自己的情况获取drawable

BitmapDrawable bd = (BitmapDrawable) d;

Bitmap bm = bd.getBitmap();
最终bm就是我们需要的Bitmap对象了。



// 从资源中获取Bitmap
public static Bitmap getBitmapFromResources(Activity act, int resId) {
Resources res = act.getResources();
return BitmapFactory.decodeResource(res, resId);
}

// byte[] → Bitmap
public static Bitmap convertBytes2Bimap(byte[] b) {
if (b.length == 0) {
return null;
}
return BitmapFactory.decodeByteArray(b, 0, b.length);
}

// Bitmap → byte[]
public static byte[] convertBitmap2Bytes(Bitmap bm) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
return baos.toByteArray();
}

// 1)Drawable → Bitmap
public static Bitmap convertDrawable2BitmapBy Canvas(Drawable drawable) {
Bitmap bitmap = Bitmap
.createBitmap(
drawable.getIntrinsicWidth(),
drawable.getIntrinsicHeight(),
drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
: Bitmap.Config.RGB_565);
Canvas canvas = new Canvas(bitmap);
// canvas.setBitmap(bitmap);
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(),
drawable.getIntrinsicHeight());
drawable.draw(canvas);
return bitmap;
}

// 2)Drawable → Bitmap
public static Bitmap convertDrawable2BitmapSi mple(Drawable drawable){
BitmapDrawable bd = (BitmapDrawable) drawable;
return bd.getBitmap();
}

// Bitmap → Drawable
public static Drawable convertBitmap2Drawable(Bitmap bitmap) {
BitmapDrawable bd = new BitmapDrawable(bitmap);
//