Bitmap 创建、转换、圆角、设置透明度

指定一个色值生成bitmap

　　 public Bitmap getBackGroundBitmap(int color) {

Paint p = new Paint();

p.setColor(Color.RED);

Bitmap bitmap = Bitmap.createBitmap(190, 110, Bitmap.Config.ARGB_8888);

Canvas canvas = new Canvas(bitmap);

canvas.drawColor(android.R.color.transparent);

canvas.drawColor(color);

return bitmap;

}

设置bitmap的透明度

　　 public static Bitmap getAlplaBitmap(Bitmap sourceImg, int number) {

　　int[] argb = new int[sourceImg.getWidth() * sourceImg.getHeight()];

　　sourceImg.getPixels(argb, 0, sourceImg.getWidth(), 0, 0, sourceImg.getWidth(), sourceImg.getHeight());

　　number = number * 255 / 100;

　　for (int i = 0; i < argb.length; i++) {

　　argb[i] = (number << 24) | (argb[i] & 0x00FFFFFF)；

　　}

　　sourceImg = Bitmap.createBitmap(argb, sourceImg.getWidth(), sourceImg.getHeight(), Config.ARGB_8888);

return sourceImg;

　　 }

drawable转换成bitmap

　　 public static Bitmap drawableToBitmap(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);

　　 drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());

　　 drawable.draw(canvas);

　　 return bitmap；

　　 }

bitmap圆角　 

 　　public static Bitmap getRoundedCornerBitmap(Bitmap bitmap) {

　　  Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),

bitmap.getHeight(), Config.ARGB_8888);

　　 Canvas canvas = new Canvas(output);

　　 final int color = Color.RED;

　　 final Paint paint = new Paint();

　　 final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());

　　 final RectF rectF = new RectF(rect);

　　 final float roundPx = 6；

　　paint.setAntiAlias(true);

　　canvas.drawARGB(0, 0, 0, 0);

　　paint.setColor(color);

　　canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

　　paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));

　　canvas.drawBitmap(bitmap, rect, rect, paint);

　　 return output;

　　 }