android控件之ViewSwitcher实现图片切换

暂时只实现了两个图片切换，多图切换还待学习

布局文件如下

 <RelativeLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ViewSwitcher
            android:id="@+id/switcher"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:inAnimation="@anim/fade_in"
            android:outAnimation="@anim/fade_out" >

            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:scaleType="fitCenter"
                android:src="@drawable/head3" />


            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:scaleType="fitCenter"
                android:src="@drawable/green_1" />
             ViewSwitcher>

        <TextView
            android:id="@+id/tap_instruction"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@id/switcher"
            android:gravity="center"
            android:text="@string/tap_to_switch" />
    RelativeLayout>

添加两个动画效果

一个是fade_in

<set xmlns:android="http://schemas.android.com/apk/res/android">
    <alpha
        android:duration="500"
        android:fromAlpha="0.0"
        android:toAlpha="1.0"
        android:interpolator="@android:anim/accelerate_interpolator" />
set>

另一个是fade_out

<set xmlns:android="http://schemas.android.com/apk/res/android">
    <alpha
        android:duration="500"
        android:fromAlpha="1.0"
        android:toAlpha="0.0"
        android:interpolator="@android:anim/accelerate_interpolator" />
set>

添加一个类

package activity;

import com.julse.com.R;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.ImageSwitcher;
import android.widget.ViewSwitcher;

public class ImageItem extends Activity{
    private ViewSwitcher imageSwitcher ;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.pic_view);


        imageSwitcher=(ViewSwitcher) findViewById(R.id.switcher);
        imageSwitcher.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                ViewSwitcher vSwitcher = (ViewSwitcher) arg0;
                if (vSwitcher.getDisplayedChild()==0) {
                    vSwitcher.showNext();
                }else {
                    vSwitcher.showPrevious();
                }
            }
        });
    }
}