/*** 转换图片成圆形* * @param bitmap* 传入Bitmap对象* @return*/public Bitmap toRoundBitmap(Bitmap bitmap) {int width = bitmap.getWidth();int height = bitmap.getHeight();float roundPx;float left, top, right, bottom, dst_left, dst_top, dst_right, dst_bottom;if (width <= height) {roundPx = width / 2;left = 0;top = 0;right = width;bottom = width;height = width;dst_left = 0;dst_top = 0;dst_right = width;dst_bottom = width;} else {roundPx = height / 2;float clip = (width - height) / 2;left = clip;right = width - clip;top = 0;bottom = height;width = height;dst_left = 0;dst_top = 0;dst_right = height;dst_bottom = height;}Bitmap output = Bitmap.createBitmap(width, height, Config.ARGB_8888);Canvas canvas = new Canvas(output);final int color = 0xff424242;final Paint paint = new Paint();final Rect src = new Rect((int) left, (int) top, (int) right, (int) bottom);final Rect dst = new Rect((int) dst_left, (int) dst_top, (int) dst_right, (int) dst_bottom);final RectF rectF = new RectF(dst);paint.setAntiAlias(true);// 设置画笔无锯齿canvas.drawARGB(0, 0, 0, 0); // 填充整个Canvaspaint.setColor(color);// 以下有两种方法画圆,drawRounRect和drawCircle// canvas.drawRoundRect(rectF, roundPx, roundPx, paint);// 画圆角矩形，第一个参数为图形显示区域，第二个参数和第三个参数分别是水平圆角半径和垂直圆角半径。canvas.drawCircle(roundPx, roundPx, roundPx, paint);paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));// 设置两张图片相交时的模式,参考/blog/1189452canvas.drawBitmap(bitmap, src, dst, paint); //以Mode.SRC_IN模式合并bitmap和已经draw了的Circlereturn output;}
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