ViewPaper实现轮播广告条

使用V4包中的viewPaper组件自定义轮播广告条效果。

实现viewpaper的滑动切换和定时自动切换效果。

上效果图

布局文件

 <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="match_parent"

     tools:context=".MainActivity" >

     <android.support.v4.view.ViewPager
         android:id="@+id/viewpaper"
         android:layout_width="fill_parent"
         android:layout_height="200dp" >
     android.support.v4.view.ViewPager>

     <LinearLayout
         android:gravity="center_horizontal"
         android:id="@+id/ll_footer"
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:layout_alignBottom="@id/viewpaper"
         android:background="#33000000"
         android:orientation="vertical" >

         <TextView
             android:id="@+id/tv_imageDesc"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content" />

         <LinearLayout

             android:id="@+id/ll_pointGroup"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:orientation="horizontal" >

         LinearLayout>
     LinearLayout>

 RelativeLayout>

还有一个selector

 xml version="1.0" encoding="utf-8"?>
 <selector xmlns:android="http://schemas.android.com/apk/res/android">

     <item android:drawable="@drawable/indicators_now" android:state_enabled="true">item>
     <item android:drawable="@drawable/indicators_default" android:state_enabled="false">item>

 selector>

class文件

 package com.example.viewpaperdemo;

 import java.util.ArrayList;
 import java.util.List;

 import android.app.Activity;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
 import android.support.v4.view.PagerAdapter;
 import android.support.v4.view.ViewPager;
 import android.support.v4.view.ViewPager.OnPageChangeListener;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.ImageView;
 import android.widget.LinearLayout;
 import android.widget.TextView;

 public class MainActivity extends Activity {
   private ViewPager viewpaper;
   private TextView tv_imageDesc;
   private LinearLayout ll_pointGroup;
   private List imageList;
   // 图片资源ID
   private final int[] imageIds = { R.drawable.a, R.drawable.b, R.drawable.c, R.drawable.d, R.drawable.e };

   // 图片标题集合
   private final String[] imageDescriptions = { "巩俐不低俗，我就不能低俗", "扑树又回来啦！再唱经典老歌引万人大合唱", "揭秘北京电影如何升级", "乐视网TV版大派送",
       "热血屌丝的反杀" };
   protected int lastPosition;

   @Override
   protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.activity_main);
     viewpaper = (ViewPager) findViewById(R.id.viewpaper);
     tv_imageDesc = (TextView) findViewById(R.id.tv_imageDesc);
     ll_pointGroup = (LinearLayout) findViewById(R.id.ll_pointGroup);
     tv_imageDesc.setText(imageDescriptions[0]);

     imageList = new ArrayList();
     for (int i = 0; i < imageIds.length; i++) {
       ImageView imageView = new ImageView(MainActivity.this);
       imageView.setImageResource(imageIds[i]);
       imageList.add(imageView);

       // 添加指示点
       ImageView point = new ImageView(this);
       LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
           LinearLayout.LayoutParams.WRAP_CONTENT);

       params.rightMargin = 15;
       point.setLayoutParams(params);

       point.setBackgroundResource(R.drawable.doet);
       if (i == 0) {
         point.setEnabled(true);
       } else {
         point.setEnabled(false);
       }
       ll_pointGroup.addView(point);
     }

     // 设置适配器
     viewpaper.setAdapter(new MyAdapter());
     // 初始化位置
     viewpaper.setCurrentItem(Integer.MAX_VALUE / 2 - (Integer.MAX_VALUE / 2 % imageList.size()));
     // 设置监听
     viewpaper.setOnPageChangeListener(new OnPageChangeListener() {
       // 滑动后
       @Override
       public void onPageSelected(int position) {
         position = position % imageList.size();

         // 设置文字描述内容
         tv_imageDesc.setText(imageDescriptions[position]);

         // 改变指示点的状态
         // 把当前点enbale 为true
         ll_pointGroup.getChildAt(position).setEnabled(true);
         // 把上一个点设为false
         ll_pointGroup.getChildAt(lastPosition).setEnabled(false);
         lastPosition = position;
         tv_imageDesc.setText(imageDescriptions[position]);
       }

       // 滑动时
       @Override
       public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
       }

       // 状态改变
       @Override
       public void onPageScrollStateChanged(int state) {
       }
     });
 isRunning=true;
    handler.sendEmptyMessageDelayed(0, 2000);

   }
   private boolean isRunning=false;
   Handler handler = new Handler() {

     @Override
     public void handleMessage(Message msg) {
       //滑动到下一页
       viewpaper.setCurrentItem(viewpaper.getCurrentItem() + 1);
       //判断是否存在 是的话就执行
       if (isRunning) {
         handler.sendEmptyMessageDelayed(0, 2000);
       }
     }
   };
   protected void onDestroy() {
     isRunning=false;

   };
   public class MyAdapter extends PagerAdapter {

     @Override
     public int getCount() {
       return Integer.MAX_VALUE;
     }

     @Override
     public boolean isViewFromObject(View view, Object object) {
       return view == object;
     }

     @Override
     public Object instantiateItem(ViewGroup container, int position) {
       position = position % imageList.size();
       container.addView(imageList.get(position));
       return imageList.get(position);
     }

     @Override
     public void destroyItem(ViewGroup container, int position, Object object) {
       container.removeView((View) object);
       object = null;
     }

   }
 }