Android 设置图片倒影效果

首先，贴出效果图：

1.布局文件main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />

    <ImageView
        android:id="@+id/picture_qian"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:src="@drawable/horse" />

</LinearLayout>

2.MainActivity界面java代码：

 package com.easymorse.picture;

 import android.app.Activity;
 import android.graphics.Bitmap;
 import android.graphics.Bitmap.Config;
 import android.graphics.Canvas;
 import android.graphics.LinearGradient;
 import android.graphics.Matrix;
 import android.graphics.Paint;
 import android.graphics.PorterDuff.Mode;
 import android.graphics.PorterDuffXfermode;
 import android.graphics.Shader.TileMode;
 import android.graphics.drawable.BitmapDrawable;
 import android.os.Bundle;
 import android.widget.ImageView;

 public class MainActivity extends Activity {
     /** Called when the activity is first created. */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
         ImageView imageView2 = (ImageView) findViewById(R.id.picture_qian);

         Bitmap bmp = ((BitmapDrawable) getResources().getDrawable(
                 R.drawable.horse)).getBitmap();

         imageView2.setImageBitmap(createReflectedImage(bmp));
     }

     public static Bitmap createReflectedImage(Bitmap originalImage) {

         final int reflectionGap = 4;

         int width = originalImage.getWidth();
         int height = originalImage.getHeight();

         Matrix matrix = new Matrix();
         matrix.preScale(1, -1);

         Bitmap reflectionImage = Bitmap.createBitmap(originalImage, 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(originalImage, 0, 0, null);

         Paint defaultPaint = new Paint();
         canvas.drawRect(0, height, width, height + reflectionGap, defaultPaint);

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

         Paint paint = new Paint();
         LinearGradient shader = new LinearGradient(0,
                 originalImage.getHeight(), 0, bitmapWithReflection.getHeight()
                         + reflectionGap, 0x70ffffff, 0x00ffffff,
                 TileMode.MIRROR);

         paint.setShader(shader);

         paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));

         canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
                 + reflectionGap, paint);

         return bitmapWithReflection;
     }
 }