Android毛玻璃效果

通常实现android毛玻璃效果，根据api等级有两种实现的方式：

1.api大于16的

2.api小于等于16的

   在公司项目中用到毛玻璃效果，因为要适配4.0一下的机型，所以只能用第二中，只看了第二种怎么实现。

下面展示一个实例：

 有两个activity ，一个MyActivity.java， 一个MainActivity

import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;public class MyActivity extends Activity implements OnClickListener{public static MyActivity instance = null;  @Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.test);findViewById(R.id.btn1).setOnClickListener(this);instance = this;}@Overridepublic void onClick(View v) {if(v.getId() == R.id.btn1){Intent intent = new Intent(this, MainActivity.class);startActivity(intent);}}}

import android.app.Activity;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.Rect;import android.graphics.drawable.BitmapDrawable;import android.os.Bundle;import android.util.DisplayMetrics;import android.view.View;import android.widget.Button;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.TextView;public class MainActivity extends Activity {private ImageView mImageView;private LinearLayout layout;private int mWidth;private int mHeight;private TextView textView;private Button btn1;private int statusBarHeight;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);layout = (LinearLayout) findViewById(R.id.ll);DisplayMetrics metrics = new DisplayMetrics();this.getWindowManager().getDefaultDisplay().getMetrics(metrics);mWidth = metrics.widthPixels;mHeight = metrics.heightPixels;Rect frame = new Rect();MyActivity.instance.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);statusBarHeight = frame.top;blur1(layout);}private void blur1(final LinearLayout ll) {int radius = 10;float scaleFactor = 8;View view = MyActivity.instance.getWindow().getDecorView();view.setDrawingCacheEnabled(true);Bitmap mBitmap = view.getDrawingCache();if (mBitmap == null) {return;}int width = mBitmap.getWidth();int height = mBitmap.getHeight();Bitmap overlay = Bitmap.createBitmap((int) (width / scaleFactor),(int) (height / scaleFactor), Bitmap.Config.ARGB_8888); //对上一个activity的截图进行处理，要不然加载会很慢Canvas canvas = new Canvas(overlay);canvas.scale(1 / scaleFactor, 1 / scaleFactor);Paint paint = new Paint();paint.setFlags(Paint.FILTER_BITMAP_FLAG);canvas.drawBitmap(mBitmap, 0, 0, paint);view.setDrawingCacheEnabled(false);final Bitmap blurBitmap = FastBlur.fastblur(this, overlay, radius);ll.post(new Runnable() {@Overridepublic void run() {ll.setBackgroundDrawable(new BitmapDrawable(blurBitmap));}});}}

下面是xml文件：activity_main.xml 和 test.xml 

test.xml 

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.androidtest12.MainActivity" >    <Button        android:id="@+id/btn1"        android:layout_width="fill_parent"        android:layout_height="50dp"        android:text="11111111" /></RelativeLayout>

activity_main.xml

<?xml version="1.0" encoding="utf-8"?><FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:id="@+id/ll"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:background="#d9101016"    android:orientation="vertical" ></FrameLayout>

还有一个实现毛玻璃效果的文件FastBlur.java

import android.content.Context;import android.graphics.Bitmap;public class FastBlur {public static 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];//        Log.e("pix", w + " " + h + " " + pix.length);        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++) {                // Preserve alpha channel: ( 0xff000000 & pix[yi] )                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;            }        }//        Log.e("pix", w + " " + h + " " + pix.length);        bitmap.setPixels(pix, 0, w, 0, 0, w, h);        return (bitmap);    }}