安卓学习-界面-ui-ViewSwitcher、ImageSwitcher和TextSwitcher

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/linearLayout1"
    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="上一张" />

        <Button
            android:id="@+id/button2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="下一张" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
        <ViewSwitcher
            android:id="@+id/viewSwitcher1"
            android:layout_width="match_parent"
            android:layout_height="match_parent" >

            <ImageView
                android:id="@+id/imageView1"
                android:layout_width="match_parent"
                android:layout_height="match_parent" />
        </ViewSwitcher>
    </LinearLayout>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>  
<set xmlns:android="http://schemas.android.com/apk/res/android">  
    <!-- 设置从右边拖进来的动画  
    android:duration指定动画持续时间  -->  
    <translate  
        android:fromXDelta="100%p"  
        android:toXDelta="0"  
        android:duration="@android:integer/config_mediumAnimTime" />  
</set>

<?xml version="1.0" encoding="utf-8"?>  
<set xmlns:android="http://schemas.android.com/apk/res/android">  
    <!-- 设置从左边拖出去的动画   
    android:duration指定动画持续时间 -->  
    <translate  
        android:fromXDelta="0"  
        android:toXDelta="-100%p"  
        android:duration="@android:integer/config_mediumAnimTime" />  
</set>  

public class MainActivity extends Activity{

    //定义图片资源
    int[] pics=new int[]{R.drawable.pic1,R.drawable.pic2,R.drawable.pic3};
    //用来判断手指是向左滑动还是向右
    float x1;
    float x2;
    
    ViewSwitcher viewSwitcher1;
    ImageView imageView1;
    //图片索引
    int index=0;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        viewSwitcher1=(ViewSwitcher)findViewById(R.id.viewSwitcher1);
        Button btn1=(Button)findViewById(R.id.button1);
        Button btn2=(Button)findViewById(R.id.button2);
        imageView1=(ImageView)findViewById(R.id.imageView1);
        
        //默认第一张图片
        imageView1.setImageResource(pics[0]);
        //上一张
        btn1.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                pre();
            }
        });
        // 下一张
        btn2.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                next();
            }
        });

        //识别手势
        viewSwitcher1.setOnTouchListener(new OnTouchListener() {
            public boolean onTouch(View v, MotionEvent event) {
                //手指按下时的坐标
                if(event.getAction()==MotionEvent.ACTION_DOWN){
                    x1=event.getX();
                }
                //手指松开时的坐标
                else if(event.getAction()==MotionEvent.ACTION_UP){
                    x2=event.getX();
                    //向左滑动
                    if(x1-x2>0){
                        Log.v("", "向左滑动");
                        next();
                        
                    }
                    //向右滑动
                    else if(x2-x1>0){
                        Log.v("", "向右滑动");
                        pre();
                    }
                }
                return true;
            }
        });
  
    }
    
    
    void next(){
        // 为ViewSwitcher的组件显示过程设置动画  
        viewSwitcher1.setInAnimation(this, R.anim.slide_in_right); 
        // 为ViewSwitcher的组件隐藏过程设置动画  
        viewSwitcher1.setOutAnimation(this, R.anim.slide_out_left);  
        if(index==2) index=0;
        else index=index+1;
        imageView1.setImageResource(pics[index]);
        viewSwitcher1.showNext();

    }
    
   void pre(){
        //为ViewSwitcher的组件显示过程设置动画  
        viewSwitcher1.setInAnimation(this, android.R.anim.slide_in_left);  
        // 为ViewSwitcher的组件隐藏过程设置动画  
        viewSwitcher1.setOutAnimation(this, android.R.anim.slide_out_right);  
        if(index==0) index=2;
        else index=index-1;
        imageView1.setImageResource(pics[index]);
        viewSwitcher1.showPrevious();
        
    }
    

}