自从iOS系统引入了Blur效果，也就是所谓的毛玻璃、模糊化效果。磨砂效果。各大系统就開始竞相模仿，这是如何的一个效果呢，我们先来看一下，如以下的图片：

效果我们知道了，怎样在Android中实现呢。说白了就是对图片进行模糊化处理，小编先给大家讲一下Android高级模糊技术的原理，例如以下：

·首先我创建了一个空的bitmap，把背景的一部分复制进去。之后我会对这个bitmap进行模糊处理并设置为TextView的背景。

·通过这个bitmap保存Canvas的状态；

·在父布局文件里把Canvas移动到TextView的位置。

·把ImageView的内容绘到bitmap中；

·此时，我们就有了一个和TextView一样大小的bitmap。它包括了ImageView的一部分内容，也就是TextView背后一层布局的内容。

·创建一个Renderscript的实例。

·把bitmap复制一份到Renderscript须要的数据片中；

·创建Renderscript模糊处理的实例；

·设置输入，半径范围然后进行模糊处理；

·把处理后的结果复制回之前的bitmap中。

·好了，我们已经把bitmap惊醒模糊处理了，能够将它设置为TextView背景了。

我近期在做一款App，当中有一个功能须要对图片处理实现毛玻璃的特效，经过一番研究，找到了3中实现方案，当中各有优缺点，假设系统的api在16以上，能够使用系统提供的方法直接处理图片，可是小编觉得下边的解决方式是实现效果最好的。

代码例如以下：

public Bitmap fastblur(Context context, Bitmap sentBitmap, int radius) {

		Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);

		if (radius < 1) {

			return (null);

		}

		int w = bitmap.getWidth();

		int h = bitmap.getHeight();

		int[] pix = new int[w * h];

		bitmap.getPixels(pix, 0, w, 0, 0, w, h);

		int wm = w - 1;

		int hm = h - 1;

		int wh = w * h;

		int div = radius + radius + 1;

		int r[] = new int[wh];

		int g[] = new int[wh];

		int b[] = new int[wh];

		int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;

		int vmin[] = new int[Math.max(w, h)];

		int divsum = (div + 1) >> 1;

		divsum *= divsum;

		int temp = 256 * divsum;

		int dv[] = new int[temp];

		for (i = 0; i < temp; i++) {

			dv[i] = (i / divsum);

		}

		yw = yi = 0;

		int[][] stack = new int[div][3];

		int stackpointer;

		int stackstart;

		int[] sir;

		int rbs;

		int r1 = radius + 1;

		int routsum, goutsum, boutsum;

		int rinsum, ginsum, binsum;

		for (y = 0; y < h; y++) {

			rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;

			for (i = -radius; i <= radius; i++) {

				p = pix[yi + Math.min(wm, Math.max(i, 0))];

				sir = stack[i + radius];

				sir[0] = (p & 0xff0000) >> 16;

				sir[1] = (p & 0x00ff00) >> 8;

				sir[2] = (p & 0x0000ff);

				rbs = r1 - Math.abs(i);

				rsum += sir[0] * rbs;

				gsum += sir[1] * rbs;

				bsum += sir[2] * rbs;

				if (i > 0) {

					rinsum += sir[0];

					ginsum += sir[1];

					binsum += sir[2];

				} else {

					routsum += sir[0];

					goutsum += sir[1];

					boutsum += sir[2];

				}

			}

			stackpointer = radius;

			for (x = 0; x < w; x++) {

				r[yi] = dv[rsum];

				g[yi] = dv[gsum];

				b[yi] = dv[bsum];

				rsum -= routsum;

				gsum -= goutsum;

				bsum -= boutsum;

				stackstart = stackpointer - radius + div;

				sir = stack[stackstart % div];

				routsum -= sir[0];

				goutsum -= sir[1];

				boutsum -= sir[2];

				if (y == 0) {

					vmin[x] = Math.min(x + radius + 1, wm);

				}

				p = pix[yw + vmin[x]];

				sir[0] = (p & 0xff0000) >> 16;

				sir[1] = (p & 0x00ff00) >> 8;

				sir[2] = (p & 0x0000ff);

				rinsum += sir[0];

				ginsum += sir[1];

				binsum += sir[2];

				rsum += rinsum;

				gsum += ginsum;

				bsum += binsum;

				stackpointer = (stackpointer + 1) % div;

				sir = stack[(stackpointer) % div];

				routsum += sir[0];

				goutsum += sir[1];

				boutsum += sir[2];

				rinsum -= sir[0];

				ginsum -= sir[1];

				binsum -= sir[2];

				yi++;

			}

			yw += w;

		}

		for (x = 0; x < w; x++) {

			rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;

			yp = -radius * w;

			for (i = -radius; i <= radius; i++) {

				yi = Math.max(0, yp) + x;

				sir = stack[i + radius];

				sir[0] = r[yi];

				sir[1] = g[yi];

				sir[2] = b[yi];

				rbs = r1 - Math.abs(i);

				rsum += r[yi] * rbs;

				gsum += g[yi] * rbs;

				bsum += b[yi] * rbs;

				if (i > 0) {

					rinsum += sir[0];

					ginsum += sir[1];

					binsum += sir[2];

				} else {

					routsum += sir[0];

					goutsum += sir[1];

					boutsum += sir[2];

				}

				if (i < hm) {

					yp += w;

				}

			}

			yi = x;

			stackpointer = radius;

			for (y = 0; y < h; y++) {

				pix[yi] = (0xff000000 & pix[yi]) | (dv[rsum] << 16)

						| (dv[gsum] << 8) | dv[bsum];

				rsum -= routsum;

				gsum -= goutsum;

				bsum -= boutsum;

				stackstart = stackpointer - radius + div;

				sir = stack[stackstart % div];

				routsum -= sir[0];

				goutsum -= sir[1];

				boutsum -= sir[2];

				if (x == 0) {

					vmin[y] = Math.min(y + r1, hm) * w;

				}

				p = x + vmin[y];

				sir[0] = r[p];

				sir[1] = g[p];

				sir[2] = b[p];

				rinsum += sir[0];

				ginsum += sir[1];

				binsum += sir[2];

				rsum += rinsum;

				gsum += ginsum;

				bsum += binsum;

				stackpointer = (stackpointer + 1) % div;

				sir = stack[stackpointer];

				routsum += sir[0];

				goutsum += sir[1];

				boutsum += sir[2];

				rinsum -= sir[0];

				ginsum -= sir[1];

				binsum -= sir[2];

				yi += w;

			}

		}

		bitmap.setPixels(pix, 0, w, 0, 0, w, h);

		return (bitmap);

	}