Android控件ImageSwitcher实现左右图片切换功能

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="vertical"  tools:context=".MainActivity" >  <ImageSwitcher    android:id="@+id/imageswitcher"    android:layout_width="200dp"    android:layout_height="200dp"    android:layout_gravity="center_horizontal" />  <RelativeLayout    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="horizontal" >    <Button      android:id="@+id/back"      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:layout_alignParentLeft="true"      android:text="back" />    <Button      android:id="@+id/forward"      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:layout_alignParentRight="true"      android:text="forward" />  </RelativeLayout></LinearLayout>

package com.example.android_imageswitcher1;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.ImageSwitcher;import android.widget.ImageView;import android.widget.ViewSwitcher.ViewFactory;public class MainActivity extends Activity implements ViewFactory,    OnClickListener {  ImageSwitcher mImageSwitcher = null;  Button btn1, btn2;  int index = 0;  int[] resId = new int[9];  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    mImageSwitcher = (ImageSwitcher) this.findViewById(R.id.imageswitcher);    btn1 = (Button) this.findViewById(R.id.back);    btn2 = (Button) this.findViewById(R.id.forward);    btn1.setOnClickListener(this);    btn2.setOnClickListener(this);    mImageSwitcher.setFactory(this);    mImageSwitcher.setInAnimation(this, android.R.anim.slide_in_left);    mImageSwitcher.setOutAnimation(this, android.R.anim.slide_out_right);    initResources();    if (resId.length > 0) {      mImageSwitcher.setImageResource(resId[0]);    }  }  public void initResources() {    resId[0] = R.drawable.adobe;    resId[1] = R.drawable.android;    resId[2] = R.drawable.circle;    resId[3] = R.drawable.digg;    resId[4] = R.drawable.flower;    resId[5] = R.drawable.gmail;    resId[6] = R.drawable.imdb;    resId[7] = R.drawable.photo;    resId[8] = R.drawable.point;  }  @Override  public View makeView() {    return new ImageView(MainActivity.this);  }  @Override  public void onClick(View view) {    int action = view.getId();    switch (action) {    case R.id.back:      index--;      if (index < 0) {        index = resId.length - 1;      }      mImageSwitcher.setImageResource(resId[index]);      break;    case R.id.forward:      index++;      if (index > resId.length - 1) {        index = 0;      }      mImageSwitcher.setImageResource(resId[index]);      break;    default:      break;    }  }}