ImageView倒影效果

先看下效果图：

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
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.os.Bundle;
import android.widget.ImageView;

public class PicActivity extends Activity {
  final int reflectionGap = 4;
  public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.picture);
        ImageView imageView = (ImageView) findViewById(R.id.pic);
       Bitmap originalImage = BitmapFactory.decodeResource(this
        .getResources(), R.drawable.car);
    int width = originalImage.getWidth();
    int height = originalImage.getHeight();

    Matrix matrix = new Matrix();
    //matrix.setRotate(30);
    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 deafaultPaint = new Paint();
    // 抗锯齿的方法
    // deafaultPaint.setAntiAlias(true);
    canvas.drawRect(0, height, width, height + reflectionGap,
        deafaultPaint);

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

    Paint paint = new Paint();
    // 抗锯齿的方法
    // paint.setAntiAlias(true);
    //线性渐变
    LinearGradient shader = new LinearGradient(0,
        originalImage.getHeight(), 0,
        bitmapWithReflection.getHeight() + reflectionGap,
        0x70ffffff, 0x00ffffff, TileMode.CLAMP);

    paint.setShader(shader);

    paint.setXfermode(new PorterDuffXfermode(Mode.DARKEN));
    canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
        + reflectionGap, paint);
    imageView.setImageBitmap(bitmapWithReflection);

}



}