<?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" >

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content" >

        <Button

            android:id="@+id/button1"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="增大透明度" />

        <Button

            android:id="@+id/button2"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="减小透明度" />

        <Button

            android:id="@+id/button3"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="下一张" />

    </LinearLayout>

    <!-- 定义显示整体图片的ImageView -->

    <ImageView

        android:id="@+id/imageView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:background="#0000ff"

        android:scaleType="fitCenter"

        android:src="@drawable/shuangta" />

    <!-- 定义显示局部图片的ImageView -->

    <ImageView

        android:id="@+id/imageView2"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_marginTop="10dp"

        android:background="#0000ff" />

</LinearLayout>

package com.example.imageview;

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.graphics.drawable.BitmapDrawable;

import android.os.Bundle;

import android.view.MotionEvent;

import android.view.View;

import android.view.View.OnClickListener;

import android.view.View.OnTouchListener;

import android.widget.Button;

import android.widget.ImageView;

public class MainActivity extends Activity {

    // 定义一个访问图片的数组

    int[] images = new int[] { R.drawable.lijiang, R.drawable.qiao,

            R.drawable.shuangta, R.drawable.shui, R.drawable.xiangbi,

            R.drawable.ic_launcher, };

    // 定义当前显示的图片

    int currentImage = 2;

    // 定义图片的初始透明度

    private int alpha = 255;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        // TODO Auto-generated method stub

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        final Button plusButton = (Button) findViewById(R.id.button1);

        final Button minuxButton = (Button) findViewById(R.id.button2);

        final Button nextButton = (Button) findViewById(R.id.button3);

        final ImageView imageview1 = (ImageView) findViewById(R.id.imageView1);

        final ImageView imageview2 = (ImageView) findViewById(R.id.imageView2);

        // 定义查看下一张图片的时间监听器

        nextButton.setOnClickListener(new OnClickListener() {

            @Override

            public void onClick(View v) {

                if (currentImage >= 5) {

                    currentImage = -1;

                }

                BitmapDrawable bitmap = (BitmapDrawable) imageview1

                        .getDrawable();

                // 如果图片还没有回收，先强制回收图片

                if (!bitmap.getBitmap().isRecycled()) {

                    bitmap.getBitmap().recycle();

                }

                // 改变ImageView的图片

                imageview1.setImageBitmap(BitmapFactory.decodeResource(

                        getResources(), images[++currentImage]));

            }

        });

        // 定义改变图片透明度的方法

        OnClickListener listener = new OnClickListener() {

            @Override

            public void onClick(View v) {

                if (v == plusButton) {

                    alpha += 20;

                }

                if (v == minuxButton) {

                    alpha -= 20;

                }

                if (alpha > 255) {

                    alpha = 255;

                }

                if (alpha <= 0) {

                    alpha = 0;

                }

                // 改变图片的透明度

                imageview1.setAlpha(alpha);

            }

        };

        // 为2个按钮添加监听器

        plusButton.setOnClickListener(listener);

        minuxButton.setOnClickListener(listener);

        imageview1.setOnTouchListener(new OnTouchListener() {

            @Override

            public boolean onTouch(View arg0, MotionEvent arg1) {

                // TODO Auto-generated method stub

                BitmapDrawable bitmapDeaw = (BitmapDrawable) imageview1

                        .getDrawable();

                // 获取第一个图片显示框中的位图

                Bitmap bitmap = bitmapDeaw.getBitmap();

                double scale = bitmap.getWidth();

                // 或许需要显示图片的开始点

                int x = (int) (arg1.getX() * scale);

                int y = (int) (arg1.getY() * scale);

                if (x + 120 > bitmap.getWidth()) {

                    x = bitmap.getWidth() - 120;

                }

                if (y + 120 > bitmap.getHeight()) {

                    y = bitmap.getHeight() - 120;

                }

                // 显示图片的指定区域

                imageview2.setImageBitmap(Bitmap.createBitmap(bitmap, x, y,

                        120, 120));

                imageview2.setAlpha(alpha);

                return false;

            }

        });

    }

}