ImageSwitcher实现图片的切换

ImageSwitcher和TextSwitcher是的子类，都是为了在选择视图时用Animation动画来展示。

下面给出代码：

package cn.com.xiebiao.test;

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 MainActivity 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;
    // 装载当前状态点的线性布局
    private LinearLayout linearLayout;
    // 当前状态点数组
    private ImageView[] tips;

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

        //图片数组，可以在SD卡中读取
        imgIds = new int[]{R.drawable.p1,R.drawable.p2,R.drawable.p3,R.drawable.p4};
        //实例化ImageSwitcher
        mImageSwitcher = (ImageSwitcher)findViewById(R.id.imageSwitcher1);

        /*****************设置Factory***********************/
        mImageSwitcher.setFactory(this);

        //设置OnTouchListener，通过Touch事件来切换图片
        mImageSwitcher.setOnTouchListener(this);

        //当前状态点的显示布局
        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 = 10;
            layoutParams.leftMargin = 10;

            mImageView.setBackgroundResource(R.drawable.tip1);
            linearLayout.addView(mImageView, layoutParams);
        }

        //默认的图片为第一张
        currentPosition =0;
        mImageSwitcher.setImageResource(imgIds[currentPosition]);
        setImageBackground(currentPosition);
    }

    /**
     * 设置选中的tip的背景
     * @param selectItems
     * tip1为未被选中的背景，灰色圆
     * tip2为被选中的背景，红色圆
     */
    private void setImageBackground(int selectItems){
        for(int i=0; i<tips.length; i++){
            if(i == selectItems){
                tips[i].setBackgroundResource(R.drawable.tip2);
            }else{
                tips[i].setBackgroundResource(R.drawable.tip1);
            }
        }
    }

    /*ViewFactory接口
    要将图片显示在ImageSwitcher控件中，必须为ImageSwitcher类设置一个ViewFactory，用来将显示的图片和父窗口区分开来。这可以通过如下方法来实现：
    mImageSwitcher.setFactory();
    此外，我们还需要实现ViewSwitcher.ViewFactory接口中的makeView()抽象方法，通过该方法可以返回一个ImageView对象，所有图片都将通过该ImageView对象来进行显示。*/
    @Override
    public View makeView() {
        final ImageView imageView = new ImageView(MainActivity.this);
        //setScaleType设置了图片的显示方式
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        return imageView ;
    }

    @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
                        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.left_out));
                        currentPosition ++ ;
                        mImageSwitcher.setImageResource(imgIds[currentPosition]);
                        setImageBackground(currentPosition);
                    }else{
                        Toast.makeText(getApplication(), "已经是最后一张", Toast.LENGTH_SHORT).show();
                    }
                }
            }

            break;
        }
        return true;
    }

<?xml version="1.0" encoding="UTF-8"?>
<FrameLayout xmlns: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>

<?xml version="1.0" encoding="UTF-8"?>
<set xmlns:android="">
    <translate
        android:fromXDelta="-100%"
        android:toXDelta="0"
        android:duration="500"/>
</set>

<shape xmlns:android=""
    android:shape="oval">
    <solid android:color="#8d9a95"/>
    <size android:width="15dp"
        android:height="15dp"/>
</shape>

其它几个xml差不多，就不贴出来了