Anroid轮播广告图

MainActivity.java:

package zkx.com.viewpager;

import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity implements ViewPager.OnPageChangeListener {

    private ViewPager viewPager;
    private ArrayList<ImageView> imageListView;
    private LinearLayout ll_point_contaniner;
    private String[] contentDesc;
    private TextView tv_desc;
    private int priviousSelectedPosition = 0;
    boolean isRunning = false;//isUIvisable
//    private ArrayList<View> pointsView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();//初始化布局View视图

        //Model数据
        initData();

        //Controller控制器
        initAdapter();

        //开启自动轮播循环
        new Thread(){
            @Override
            public void run() {
                isRunning = true;
                while(isRunning ){
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            System.out.println("设置当前位置: " + viewPager.getCurrentItem());
                            //往下跳一位
                            viewPager.setCurrentItem(viewPager.getCurrentItem() + 1);
                        }
                    });


                }
            }
        }.start();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        isRunning=false;//界面销毁置为false
    }

    private void initView() {
        viewPager= (ViewPager) findViewById(R.id.viewPager);
        viewPager.setOnPageChangeListener(this);//设置滚动监听
        //viewPager.setOffscreenPageLimit(1);//左右各保留几个对象
        ll_point_contaniner= (LinearLayout) findViewById(R.id.ll_point_contaniner);

        tv_desc = (TextView) findViewById(R.id.tv_desc);

    }

    private void initData() {
        //初始化要显示的数据

        //图片资源id数组
        int[] imageResIds=new int[]{R.drawable.a,R.drawable.b,R.drawable.c,R.drawable.d,R.drawable.e};

        //文本描述
        contentDesc = new String[]{
                "周杰伦",
                "张学友",
                "李克勤",
                "陈奕迅",
                "郑中基"
        };
        //初始化要展示的5个imageView
        imageListView= new ArrayList<ImageView>();
//        pointsView =new ArrayList<View>();
        ImageView imageView;
        View pointView;
        LinearLayout.LayoutParams layoutParams;
        for (int i = 0; i <imageResIds.length ; i++) {
            imageView = new ImageView(this);
            imageView.setBackgroundResource(imageResIds[i]);
            imageListView.add(imageView);
            //加小白点，指示器
            pointView=new View(this);
            pointView.setBackgroundResource(R.drawable.seletor_bg_point);
            layoutParams= new LinearLayout.LayoutParams(5,5);
            if(i!=0) layoutParams.leftMargin = 15;
            pointView.setEnabled(false);
            ll_point_contaniner.addView(pointView,layoutParams);
        }
    }

    private void initAdapter() {

        ll_point_contaniner.getChildAt(0).setEnabled(true);
        tv_desc.setText(contentDesc[0]);

        //设置适配器
        viewPager.setAdapter(new MyAdpater());
        //(为了实现向左无限循环)默认到中间的某个位置
//        int pos=Integer.MAX_VALUE/2-(Integer.MAX_VALUE/2%imageListView.size());
        viewPager.setCurrentItem(5000000);//设置到某个位置

    }

    class MyAdpater extends PagerAdapter{
        @Override
        public int getCount() {
//            return imageListView.size();
            return Integer.MAX_VALUE;//伪无限循环
        }

        //1.返回要显示的内容，创建条目
        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            System.out.println("instantiateItem初始化: "+position);
            //container:容器:ViewPager
            //position:当前要显示条目的位置
            int newPosition = position%imageListView.size();
            ImageView imageView =imageListView.get(newPosition);
            //a.把View对象添加到container中
            container.addView(imageView);
            //b.把View对象返回给框架(适配器)
            return imageView;//必需重写，否则报异常
        }

        /**
         *2.销毁条目
         * @param container
         * @param position
         * @param object 要销毁的对象
         */
        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            System.out.println("destroyItem销毁: "+position);
            container.removeView((View) object);
        }

        //3.指定复用的判断逻辑,固定写法
        @Override
        public boolean isViewFromObject(View view, Object object) {
            //当滑到新的条目时，又返回来 ，view是否可以被复用
            //返回判断规则
            return view==object;
        }
    }

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


    @Override
    public void onPageSelected(int position) {
        //新的条目被选中时调用
        System.out.println("onPageSelected: " + position);
        int newPosition = position%imageListView.size();
        tv_desc.setText(contentDesc[newPosition]);
//        for (int i = 0; i < ll_point_contaniner.getChildCount(); i++) {
//            ll_point_contaniner.getChildAt(position).setEnabled(position==i);
//        }
        //把之前的禁用,把最新的启用，更新指示器
        // (顺序不能调换,因为第一个显示的priviousSelectedPosition==newPosition==0,调换后，第一个显示的点将被禁掉)
        ll_point_contaniner.getChildAt(priviousSelectedPosition).setEnabled(false);//之前的禁用
        ll_point_contaniner.getChildAt(newPosition).setEnabled(true);//最新的(现在的)启用
        priviousSelectedPosition = newPosition;//记录之前的位置
    }

    @Override
    public void onPageScrollStateChanged(int state) {
        //滚动状态变化时调用
    }
}

 

activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<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="zkx.com.viewpager.MainActivity">
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="160dp">
        <android.support.v4.view.ViewPager
            android:id="@+id/viewPager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="40dp"
            android:orientation="vertical"
            android:padding="5dp"
            android:background="#66000000"
            android:layout_alignParentBottom="true"
            android:gravity="center_horizontal">
            <TextView
                android:id="@+id/tv_desc"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textColor="@android:color/white"
                android:singleLine="true"
                android:text="天王盖地虎,天王盖地虎,天王盖地虎"/>
            <LinearLayout
                android:id="@+id/ll_point_contaniner"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="5dp"
                android:orientation="horizontal"></LinearLayout>
        </LinearLayout>
    </RelativeLayout>
    

</RelativeLayout>

 以下三个xml文件建在drawable目录下

seletor_bg_point.xml:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_enabled="true" android:drawable="@drawable/shape_bg_point_enable"/>
    <item android:state_enabled="false" android:drawable="@drawable/shape_bg_point_disable"/>
</selector>

 

shape_bg_point_disable.xml:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <corners android:radius="5dp"/>
    <solid android:color="@android:color/darker_gray"/>
</shape>

 

shape_bg_point_enable.xml:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <corners android:radius="5dp"/>
    <solid android:color="#FFFFFF"/>
</shape>

 轮播广告图需要用的图片资源可以在附件中下载,也可以用自己指定的图片