毛玻璃背景效果

Posted wlwqnj

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在正常的开发中,经常会遇到打开一个界面,只打开的一半,这种情况,背景怎么去处理?

其实使用毛玻璃虚化是最方便的处理方法。

这个首先就需要获取到,这个时候背景图片的截图。可以通过DrawCache来获取。

view.setDrawingCacheEnabled(true);//设置能否缓存图片信息(drawing cache
view.buildDrawingCache();//如果能够缓存图片,则创建图片缓存
Bitmap bitmap = view.getDrawingCache();//如果图片已经缓存,返回一个bitmap
Bitmap bitmap1 = FastBlurUtils.toBlur(bitmap, 5);    //这个方法就是把得到的bitmap缓存,转换为毛玻璃的效果,具体方法直接上代码,拿去就可以使用。  参数 5 增大,可以得到更高程度的虚化,不过会导致CPU更加intensive
iv.setImageBitmap(bitmap1);
mChatListView.destroyDrawingCache();//使用完之后,释放缓存占用的资源

Glide通过transform也可以转化为毛玻璃效果,但是试了几次都没有成功。
 .bitmapTransform(new CropCircleTransformation(this))    //这个是转换为圆形。   添加下面这个依赖库,  可以进行很多的图片转换
.bitmapTransform(new BlurTransformation(context, 25), new CropCircleTransformation(context))    //对图片进行虚化和圆形裁剪,两个效果一起加上,就这样使用,用“,”隔开就可以了
 
compile ‘jp.wasabeef:glide-transformations:2.0.2‘


这个类可以直接拿去使用
public class FastBlurUtils {
/**
* 根据imagepath获取bitmap
*/
/**
* 得到本地或者网络上的bitmap url - 网络或者本地图片的绝对路径,比如:
* <p>
* A.网络路径: url="http://blog.foreverlove.us/girl2.png" ;
* <p>
* B.本地路径:url="file://mnt/sdcard/photo/image.png";
* <p>
* C.支持的图片格式 ,png, jpg,bmp,gif等等
*
* @param url
* @return
*/
public static int IO_BUFFER_SIZE = 2 * 1024;

public static Bitmap GetUrlBitmap(String url, int scaleRatio) {
int blurRadius = 8;//通常设置为8就行。
if (scaleRatio <= 0) {
scaleRatio = 10;
}

Bitmap originBitmap = null;
InputStream in = null;
BufferedOutputStream out = null;
try {
in = new BufferedInputStream(new URL(url).openStream(), IO_BUFFER_SIZE);
final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
copy(in, out);
out.flush();
byte[] data = dataStream.toByteArray();
originBitmap = BitmapFactory.decodeByteArray(data, 0, data.length);

Bitmap scaledBitmap = Bitmap.createScaledBitmap(originBitmap,
originBitmap.getWidth() / scaleRatio,
originBitmap.getHeight() / scaleRatio,
false);
Bitmap blurBitmap = doBlur(scaledBitmap, blurRadius, true);
return blurBitmap;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}

private static void copy(InputStream in, OutputStream out)
throws IOException {
byte[] b = new byte[IO_BUFFER_SIZE];
int read;
while ((read = in.read(b)) != -1) {
out.write(b, 0, read);
}
}

// 把本地图片毛玻璃化
public static Bitmap toBlur(Bitmap originBitmap, int scaleRatio) {
// int scaleRatio = 10;
// 增大scaleRatio缩放比,使用一样更小的bitmap去虚化可以到更好的得模糊效果,而且有利于占用内存的减小;
int blurRadius = 5;//通常设置为8就行。
//增大blurRadius,可以得到更高程度的虚化,不过会导致CPU更加intensive


/* 其中前三个参数很明显,其中宽高我们可以选择为原图尺寸的1/10
第四个filter是指缩放的效果,filtertrue则会得到一个边缘平滑的bitmap
反之,则会得到边缘锯齿、pixelrelatedbitmap
这里我们要对缩放的图片进行虚化,所以无所谓边缘效果,filter=false*/
if (scaleRatio <= 0) {
scaleRatio = 10;
}
Bitmap scaledBitmap = Bitmap.createScaledBitmap(originBitmap,
originBitmap.getWidth() / scaleRatio,
originBitmap.getHeight() / scaleRatio,
false);
Bitmap blurBitmap = doBlur(scaledBitmap, blurRadius, true);
return blurBitmap;
}

public static Bitmap doBlur(Bitmap sentBitmap, int radius, boolean canReuseInBitmap) {
Bitmap bitmap;
if (canReuseInBitmap) {
bitmap = sentBitmap;
} else {
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 dv[] = new int[256 * divsum];
for (i = 0; i < 256 * divsum; 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;
}
}
bitmap.setPixels(pix, 0, w, 0, 0, w, h);
return (bitmap);
}
}

 

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