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

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

 

 

 

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:

 

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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;  

    }  

      

} 

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:

 

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

<LinearLayout xmlns: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> 

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

<LinearLayout xmlns: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