Android 基于ImageSwitcher实现的左右切换图片

左右切换图片控件大家都用ViewPager, ViewFipper比较多吧，我之前也用ViewPager实现了，使用ViewPager实现左右循环滑动图片，有兴趣的可以去看下，今天介绍的是基于ImageSwitcher实现的左右切换图片，先上截图吧

好了，接下来来看代码吧，第一张图是一个GridView，点击item跳转到第二个界面，第一个界面可以忽略，主要是讲解ImageSwitcher的左右却换图片，先看布局文件

 <?xml version="1.0" encoding="UTF-8"?>
 <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent" >
     <ImageSwitcher
         android:id="@+id/imageSwitcher1"
         android:layout_width="fill_parent"
         android:layout_height="fill_parent">
     </ImageSwitcher>

     <RelativeLayout
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:orientation="vertical" >
         <LinearLayout
             android:id="@+id/viewGroup"
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:layout_alignParentBottom="true"
             android:layout_marginBottom="30dp"
             android:gravity="center_horizontal"
             android:orientation="horizontal" >
         </LinearLayout>
     </RelativeLayout>
 </FrameLayout>

然后就是Activity代码啦，总体来说比较简单，代码我添加了注释

 package com.example.photoalbum;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.View.OnTouchListener;
 import android.view.ViewGroup;
 import android.view.animation.AnimationUtils;
 import android.widget.ImageSwitcher;
 import android.widget.ImageView;
 import android.widget.LinearLayout;
 import android.widget.RelativeLayout.LayoutParams;
 import android.widget.Toast;
 import android.widget.ViewSwitcher.ViewFactory;

 public class ShowPhotoActivity extends Activity implements ViewFactory, OnTouchListener{
     /**
      * ImagaSwitcher 的引用
      */
     private ImageSwitcher mImageSwitcher;
     /**
      * 图片id数组
      */
     private int[] imgIds;
     /**
      * 当前选中的图片id序号
      */
     private int currentPosition;
     /**
      * 按下点的X坐标
      */
     private float downX;
     /**
      * 装载点点的容器
      */
     private LinearLayout linearLayout;
     /**
      * 点点数组
      */
     private ImageView[] tips;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.show_photo);

         imgIds = new int[]{R.drawable.item01,R.drawable.item02,R.drawable.item03,R.drawable.item04,
                 R.drawable.item05, R.drawable.item06, R.drawable.item07, R.drawable.item08,R.drawable.item09,
                 R.drawable.item10, R.drawable.item11, R.drawable.item12};
         //实例化ImageSwitcher
         mImageSwitcher  = (ImageSwitcher) findViewById(R.id.imageSwitcher1);
         //设置Factory
         mImageSwitcher.setFactory(this);
         //设置OnTouchListener，我们通过Touch事件来切换图片
         mImageSwitcher.setOnTouchListener(this);

         linearLayout = (LinearLayout) findViewById(R.id.viewGroup);

         tips = new ImageView[imgIds.length];
         for(int i=0; i<imgIds.length; i++){
             ImageView mImageView = new ImageView(this);
             tips[i] = mImageView;
             LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(new ViewGroup.LayoutParams(LayoutParams.WRAP_CONTENT,
                     LayoutParams.WRAP_CONTENT));
             layoutParams.rightMargin = 3;
             layoutParams.leftMargin = 3;

             mImageView.setBackgroundResource(R.drawable.page_indicator_unfocused);
             linearLayout.addView(mImageView, layoutParams);
         }

         //这个我是从上一个界面传过来的，上一个界面是一个GridView
         currentPosition = getIntent().getIntExtra("position", 0);
         mImageSwitcher.setImageResource(imgIds[currentPosition]);

         setImageBackground(currentPosition);

     }

      /**
      * 设置选中的tip的背景
      * @param selectItems
      */
     private void setImageBackground(int selectItems){
         for(int i=0; i<tips.length; i++){
             if(i == selectItems){
                 tips[i].setBackgroundResource(R.drawable.page_indicator_focused);
             }else{
                 tips[i].setBackgroundResource(R.drawable.page_indicator_unfocused);
             }
         }
     }

     @Override
     public View makeView() {
         final ImageView i = new ImageView(this);
         i.setBackgroundColor(0xff000000);
         i.setScaleType(ImageView.ScaleType.CENTER_CROP);
         i.setLayoutParams(new ImageSwitcher.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
         return i ;
     }

     @Override
     public boolean onTouch(View v, MotionEvent event) {
         switch (event.getAction()) {
         case MotionEvent.ACTION_DOWN:{
             //手指按下的X坐标
             downX = event.getX();
             break;
         }
         case MotionEvent.ACTION_UP:{
             float lastX = event.getX();
             //抬起的时候的X坐标大于按下的时候就显示上一张图片
             if(lastX > downX){
                 if(currentPosition > 0){
                     //设置动画，这里的动画比较简单，不明白的去网上看看相关内容
                     mImageSwitcher.setInAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.left_in));
                     mImageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.right_out));
                     currentPosition --;
                     mImageSwitcher.setImageResource(imgIds[currentPosition % imgIds.length]);
                     setImageBackground(currentPosition);
                 }else{
                     Toast.makeText(getApplication(), "已经是第一张", Toast.LENGTH_SHORT).show();
                 }
             }

             if(lastX < downX){
                 if(currentPosition < imgIds.length - 1){
                     mImageSwitcher.setInAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.right_in));
                     mImageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.lift_out));
                     currentPosition ++ ;
                     mImageSwitcher.setImageResource(imgIds[currentPosition]);
                     setImageBackground(currentPosition);
                 }else{
                     Toast.makeText(getApplication(), "到了最后一张", Toast.LENGTH_SHORT).show();
                 }
             }
             }

             break;
         }

         return true;
     }

 }

上面切换图片主要用到的就是动画了，用的是translate移动动画，不了解动画的同学到这里看看 http://blog.csdn.net/xiaanming/article/details/8997260 ，我就不介绍了，接下来我吧动画代码贴出来，在res新建一个anim的目录，如下图

左边进入的动画，left_in.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <set xmlns:android="http://schemas.android.com/apk/res/android">
     <translate
         android:fromXDelta="-100%p"
         android:toXDelta="0"
         android:duration="500"/>
 </set>

左边出去的动画,left_out.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <set xmlns:android="http://schemas.android.com/apk/res/android">
     <translate
         android:fromXDelta="0"
         android:toXDelta="-100%p"
         android:duration="500"/>
 </set>

右边进入的动画，right_in.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <set xmlns:android="http://schemas.android.com/apk/res/android">
     <translate
         android:fromXDelta="100%p"
         android:toXDelta="0"
         android:duration="500"/>
 </set>

右边出去的动画,right_out.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <set xmlns:android="http://schemas.android.com/apk/res/android">
     <translate
         android:fromXDelta="0"
         android:toXDelta="100%p"
         android:duration="500"/>
 </set>

好了，介绍完了，代码写的不是很好，写的不好的地方希望您指出，谢谢

代码下载