android控件之ViewSwitcher实现图片切换

<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>

<?xml version="1.0" encoding="utf-8"?>
<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>

<?xml version="1.0" encoding="utf-8"?>

<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>

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();
}
}
});
}
}