Android 几种图像特效处理的集锦

最新推荐文章于 2021-05-28 14:31:25 发布

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本博客展示了如何在Android应用中使用自定义库处理和显示图片，包括图片缩放、转为Bitmap、圆角处理及添加倒影效果。

第一步:新建一个Android工程命名为ImageDemo,工程结构如下:

第二步.java文件ImageUtil.java,在里面定义一些图片处理方法<span color:#333333;"="" style="font-size: 10.5pt; ">,代码如下:

 
package com.android.tutor;  
 
import android.graphics.Bitmap;  
 
import android.graphics.Canvas;  
 
import android.graphics.LinearGradient;  
 
import android.graphics.Matrix;  
 
import android.graphics.Paint;  
 
import android.graphics.PixelFormat;  
 
import android.graphics.PorterDuffXfermode;  
 
import android.graphics.Rect;  
 
import android.graphics.RectF;  
 
import android.graphics.Bitmap.Config;  
 
import android.graphics.PorterDuff.Mode;  
 
import android.graphics.Shader.TileMode;  
 
import android.graphics.drawable.Drawable;  
 
public class ImageUtil {  
 
       
 
    //放大缩小图片   
 
    public static Bitmap zoomBitmap(Bitmap bitmap,int w,int h){  
 
        int width = bitmap.getWidth();  
 
        int height = bitmap.getHeight();  
 
        Matrix matrix = new Matrix();  
 
        float scaleWidht = ((float)w / width);  
 
        float scaleHeight = ((float)h / height);  
 
        matrix.postScale(scaleWidht, scaleHeight);  
 
        Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);  
 
        return newbmp;  
 
    }  
 
    //将Drawable转化为Bitmap   
 
     public static Bitmap drawableToBitmap(Drawable drawable){  
 
            int width = drawable.getIntrinsicWidth();  
 
            int height = drawable.getIntrinsicHeight();  
 
            Bitmap bitmap = Bitmap.createBitmap(width, height,  
 
                    drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888  
 
                            : Bitmap.Config.RGB_565);  
 
            Canvas canvas = new Canvas(bitmap);  
 
            drawable.setBounds(0,0,width,height);  
 
            drawable.draw(canvas);  
 
            return bitmap;  
 
               
 
        }  
 
        
 
     //获得圆角图片的方法   
 
    public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){  
 
           
 
        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap  
 
                .getHeight(), Config.ARGB_8888);  
 
        Canvas canvas = new Canvas(output);  
 
    
 
        final int color = 0xff424242;  
 
        final Paint paint = new Paint();  
 
        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());  
 
        final RectF rectF = new RectF(rect);  
 
    
 
        paint.setAntiAlias(true);  
 
        canvas.drawARGB(0, 0, 0, 0);  
 
        paint.setColor(color);  
 
        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);  
 
    
 
        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));  
 
        canvas.drawBitmap(bitmap, rect, rect, paint);  
 
    
 
        return output;  
 
    }  
 
    //获得带倒影的图片方法   
 
    public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap){  
 
        final int reflectionGap = 4;  
 
        int width = bitmap.getWidth();  
 
        int height = bitmap.getHeight();  
 
           
 
        Matrix matrix = new Matrix();  
 
        matrix.preScale(1, -1);  
 
           
 
        Bitmap reflectionImage = Bitmap.createBitmap(bitmap,   
 
                0, height/2, width, height/2, matrix, false);  
 
           
 
        Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height/2), Config.ARGB_8888);  
 
           
 
        Canvas canvas = new Canvas(bitmapWithReflection);  
 
        canvas.drawBitmap(bitmap, 0, 0, null);  
 
        Paint deafalutPaint = new Paint();  
 
        canvas.drawRect(0, height,width,height + reflectionGap,  
 
                deafalutPaint);  
 
           
 
        canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null);  
 
           
 
        Paint paint = new Paint();  
 
        LinearGradient shader = new LinearGradient(0,  
 
                bitmap.getHeight(), 0, bitmapWithReflection.getHeight()  
 
                + reflectionGap, 0x70ffffff, 0x00ffffff, TileMode.CLAMP);  
 
        paint.setShader(shader);  
 
        // Set the Transfer mode to be porter duff and destination in   
 
        paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));  
 
        // Draw a rectangle using the paint with our linear gradient   
 
        canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()  
 
                + reflectionGap, paint);  
 
    
 
        return bitmapWithReflection;  
 
    }  
 
       
 
}

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

 
    1 <!--?xml version="1.0" encoding="utf-8"?-->   
 
    2

第四步:修改主核心程序,ImageDemo.java,代码如下:

 
package com.android.tutor;  
 
import android.app.Activity;  
 
import android.graphics.Bitmap;  
 
import android.graphics.drawable.Drawable;  
 
import android.os.Bundle;  
 
import android.widget.ImageView;  
 
public class Imagedemo extends Activity {  
 
    private ImageView mImageView01,mImageView02;  
 
       
 
    public void onCreate(Bundle savedInstanceState) {  
 
        super.onCreate(savedInstanceState);  
 
        setContentView(R.layout.main);  
 
        setupViews();  
 
    }  
 
      
 
    private void setupViews(){  
 
        mImageView01 = (ImageView)findViewById(R.id.image01);  
 
        mImageView02 = (ImageView)findViewById(R.id.image02);  
 
           
 
        //获取壁纸返回值是Drawable   
 
        Drawable drawable = getWallpaper();  
 
        //将Drawable转化为Bitmap   
 
        Bitmap bitmap = ImageUtil.drawableToBitmap(drawable);  
 
        //缩放图片   
 
        Bitmap zoomBitmap = ImageUtil.zoomBitmap(bitmap, 100, 100);  
 
        //获取圆角图片   
 
        Bitmap roundBitmap = ImageUtil.getRoundedCornerBitmap(zoomBitmap, 10.0f);  
 
        //获取倒影图片   
 
        Bitmap reflectBitmap = ImageUtil.createReflectionImageWithOrigin(zoomBitmap);  
 
        //这里可以让Bitmap再转化为Drawable   
 
//      Drawable roundDrawable = new BitmapDrawable(roundBitmap);          
 
//      Drawable reflectDrawable = new BitmapDrawable(reflectBitmap);          
 
//      mImageView01.setBackgroundDrawable(roundDrawable);   
 
//      mImageView02.setBackgroundDrawable(reflectDrawable);   
 
                   
 
        mImageView01.setImageBitmap(roundBitmap);  
 
        mImageView02.setImageBitmap(reflectBitmap);  
 
    }  
 
         
 
          
 
}