Android中几种图像特效处理的集锦!!

大家好,这一节给大家分享的是Android中几种图像特效处理的小技巧,比如圆角,倒影,还有就是图片缩放,Drawable转化为Bitmap,Bitmap转化为Drawable等等.

废话少说了,直接讲解今天的实例,本例主要是先获取壁纸(getWallpaper()),然后对当前壁纸的一些特效处理.大家按步骤一步一步来:

第一步:新建一个Android工程命名为ImageDemo,工程结构如下:

第二步:新建一个.java文件,命名为ImageUtil.java,在里面定义一些图片处理方法,代码如下:

packagecom.android.tutor;
importandroid.graphics.Bitmap;
importandroid.graphics.Canvas;
importandroid.graphics.LinearGradient;
importandroid.graphics.Matrix;
importandroid.graphics.Paint;
importandroid.graphics.PixelFormat;
importandroid.graphics.PorterDuffXfermode;
importandroid.graphics.Rect;
importandroid.graphics.RectF;
importandroid.graphics.Bitmap.Config;
importandroid.graphics.PorterDuff.Mode;
importandroid.graphics.Shader.TileMode;
importandroid.graphics.drawable.Drawable;
publicclassImageUtil{

//放大缩小图片
publicstaticBitmapzoomBitmap(Bitmapbitmap,intw,inth){
intwidth=bitmap.getWidth();
intheight=bitmap.getHeight();
Matrixmatrix=newMatrix();
floatscaleWidht=((float)w/width);
floatscaleHeight=((float)h/height);
matrix.postScale(scaleWidht,scaleHeight);
Bitmapnewbmp=Bitmap.createBitmap(bitmap,0,0,width,height,matrix,true);
returnnewbmp;
}
//将Drawable转化为Bitmap
publicstaticBitmapdrawableToBitmap(Drawabledrawable){
intwidth=drawable.getIntrinsicWidth();
intheight=drawable.getIntrinsicHeight();
Bitmapbitmap=Bitmap.createBitmap(width,height,
drawable.getOpacity()!=PixelFormat.OPAQUE?Bitmap.Config.ARGB_8888
:Bitmap.Config.RGB_565);
Canvascanvas=newCanvas(bitmap);
drawable.setBounds(0,0,width,height);
drawable.draw(canvas);
returnbitmap;

}

//获得圆角图片的方法
publicstaticBitmapgetRoundedCornerBitmap(Bitmapbitmap,floatroundPx){

Bitmapoutput=Bitmap.createBitmap(bitmap.getWidth(),bitmap
.getHeight(),Config.ARGB_8888);
Canvascanvas=newCanvas(output);

finalintcolor=0xff424242;
finalPaintpaint=newPaint();
finalRectrect=newRect(0,0,bitmap.getWidth(),bitmap.getHeight());
finalRectFrectF=newRectF(rect);

paint.setAntiAlias(true);
canvas.drawARGB(0,0,0,0);
paint.setColor(color);
canvas.drawRoundRect(rectF,roundPx,roundPx,paint);

paint.setXfermode(newPorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(bitmap,rect,rect,paint);

returnoutput;
}
//获得带倒影的图片方法
publicstaticBitmapcreateReflectionImageWithOrigin(Bitmapbitmap){
finalintreflectionGap=4;
intwidth=bitmap.getWidth();
intheight=bitmap.getHeight();

Matrixmatrix=newMatrix();
matrix.preScale(1,-1);

BitmapreflectionImage=Bitmap.createBitmap(bitmap,
0,height/2,width,height/2,matrix,false);

BitmapbitmapWithReflection=Bitmap.createBitmap(width,(height+height/2),Config.ARGB_8888);

Canvascanvas=newCanvas(bitmapWithReflection);
canvas.drawBitmap(bitmap,0,0,null);
PaintdeafalutPaint=newPaint();
canvas.drawRect(0,height,width,height+reflectionGap,
deafalutPaint);

canvas.drawBitmap(reflectionImage,0,height+reflectionGap,null);

Paintpaint=newPaint();
LinearGradientshader=newLinearGradient(0,
bitmap.getHeight(),0,bitmapWithReflection.getHeight()
+reflectionGap,0x70ffffff,0x00ffffff,TileMode.CLAMP);
paint.setShader(shader);
//SettheTransfermodetobeporterduffanddestinationin
paint.setXfermode(newPorterDuffXfermode(Mode.DST_IN));
//Drawarectangleusingthepaintwithourlineargradient
canvas.drawRect(0,height,width,bitmapWithReflection.getHeight()
+reflectionGap,paint);

returnbitmapWithReflection;
}

}

第三步:修改main.xml布局文件,主要放了两个ImageView控件,代码如下:

<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ImageView
android:id="@+id/image01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10px"
/>
<ImageView
android:id="@+id/image02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10px"
/>
</LinearLayout>

第四步:修改主核心程序,ImageDemo.java,代码如下:

packagecom.android.tutor;
importandroid.app.Activity;
importandroid.graphics.Bitmap;
importandroid.graphics.drawable.Drawable;
importandroid.os.Bundle;
importandroid.widget.ImageView;
publicclassImagedemoextendsActivity{
privateImageViewmImageView01,mImageView02;

publicvoidonCreate(BundlesavedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setupViews();
}

privatevoidsetupViews(){
mImageView01=(ImageView)findViewById(R.id.image01);
mImageView02=(ImageView)findViewById(R.id.image02);

//获取壁纸返回值是Drawable
Drawabledrawable=getWallpaper();
//将Drawable转化为Bitmap
Bitmapbitmap=ImageUtil.drawableToBitmap(drawable);
//缩放图片
BitmapzoomBitmap=ImageUtil.zoomBitmap(bitmap,100,100);
//获取圆角图片
BitmaproundBitmap=ImageUtil.getRoundedCornerBitmap(zoomBitmap,10.0f);
//获取倒影图片
BitmapreflectBitmap=ImageUtil.createReflectionImageWithOrigin(zoomBitmap);
//这里可以让Bitmap再转化为Drawable
//DrawableroundDrawable=newBitmapDrawable(roundBitmap);
//DrawablereflectDrawable=newBitmapDrawable(reflectBitmap);
//mImageView01.setBackgroundDrawable(roundDrawable);
//mImageView02.setBackgroundDrawable(reflectDrawable);

mImageView01.setImageBitmap(roundBitmap);
mImageView02.setImageBitmap(reflectBitmap);
}


}

第五步:运行上述工程,查看效果如下:

OK大功告成了!!

原文地址：http://blog.csdn.net/android_tutor/article/details/5981753