![ViewPager实现自动翻页功能 --转载出处找不到了，根据自己的理解写个随笔方便以后的记忆以及代码的共享，感谢给我启发的那位高手--第一次写博客哈]( "ViewPager实现自动翻页功能 --转载出处找不到了，根据自己的理解写个随笔方便以后的记忆以及代码的共享，感谢给我启发的那位高手--第一次写博客哈")
xml文件 textview 用于显示图片的标题 viewpager 用于实现翻页效果
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center" >
<TextView
android:id="@+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#123456"
android:textIsSelectable="true"
android:textSize="18sp" />
</LinearLayout>
<android.support.v4.view.ViewPager
android:id="@+id/vp"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
</android.support.v4.view.ViewPager>
</LinearLayout>
代码块
package com.xiang;
import java.util.ArrayList;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import android.os.Bundle;
import android.os.Handler;
import android.app.Activity;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.Menu;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;
public class AutoScrollActivity extends Activity {
private ViewPager vp;
private int imagsID[]={R.drawable.a,R.drawable.b,R.drawable.c,R.drawable.d};
private String titles[]={"图片一","图片二","图片三","图片四"};
private ArrayList<ImageView> images;
private TextView title;
private ViewPagerAdapter adapter;
private int currentPosition=0;//当前页面位置
private ScheduledExecutorService executor;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_auto_scroll);
init();
}
private void init() {
images=new ArrayList<ImageView>();
for(int i=0;i<imagsID.length;i++)
{
ImageView imgview=new ImageView(this);
imgview.setBackgroundResource(imagsID[i]);
images.add(imgview);
}
title=(TextView)findViewById(R.id.title);
title.setText(titles[0]);//默认显示第一张图片
vp=(ViewPager)findViewById(R.id.vp);
adapter=new ViewPagerAdapter();
vp.setAdapter(adapter);
vp.setOnPageChangeListener(listener);
}
OnPageChangeListener listener=new OnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
// TODO Auto-generated method stub
title.setText(titles[arg0]);
currentPosition=arg0;
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
@Override
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
};
class ViewPagerAdapter extends PagerAdapter
{
@Override
public int getCount() {
// TODO Auto-generated method stub
return images.size();
}
@Override
public boolean isViewFromObject(View arg0, Object arg1) {
// TODO Auto-generated method stub
return arg0==arg1;//判断两次图片是否一样
}
@Override
public Object instantiateItem(View container, int position) {
// TODO Auto-generated method stub
ViewPager vp=(ViewPager) container;
vp.addView(images.get(position));
return images.get(position);
}
@Override
public void destroyItem(View container, int position, Object object) {
// TODO Auto-generated method stub
ViewPager vp=(ViewPager) container;
vp.removeView(images.get(position));
}
}
@Override
protected void onStart() {
// TODO Auto-generated method stub
/*
* 第一个参数：要自动执行的方法（任务）
* 第二个参数：延迟几秒启动
* 第三个参数：之后每个几秒 执行第一个参数的方法
* 第四个参数：时间单位 时分秒
*/
super.onStart();
executor=Executors.newSingleThreadScheduledExecutor();
executor.scheduleAtFixedRate(new ViewPagerTask(), 2, 2, TimeUnit.SECONDS);
}
class ViewPagerTask implements Runnable
{
@Override
public void run() {
// TODO Auto-generated method stub
currentPosition=(currentPosition+1)%images.size();
handler.obtainMessage().sendToTarget();//获取当前消息 发送给handler
}
}
private Handler handler=new Handler()
{
public void handleMessage(android.os.Message msg) {
vp.setCurrentItem(currentPosition);
};
};
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.auto_scroll, menu);
return true;
}
}
实现效果：图片每隔两秒自动翻页，同时更改图片的标题，到最后一面又返回到第一页显示。2013-10-17
