ViewPager轮播图

.activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    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/viewpager_vp"
        android:layout_width="wrap_content"
        android:layout_height="250dp" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#88000000"
        android:orientation="vertical"
        android:padding="8dp"
        android:gravity="center_horizontal"
        android:layout_alignBottom="@+id/viewpager_vp">

        <TextView
            android:id="@+id/ViewPager_tv"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textColor="@android:color/white"
            android:text="AAAAA"/>

        <LinearLayout
            android:id="@+id/ll_dot"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="horizontal">


        </LinearLayout>

    </LinearLayout>

</RelativeLayout>

.MainActivity

package com.example.lunbo;

import android.os.Handler;
import android.os.Message;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    private ViewPager viewpager_vp;
    private ArrayList<ImageView> ImageViews = new ArrayList();
    private int[] imageResIds = {
            R.drawable.a,
            R.drawable.b,
            R.drawable.c,
            R.drawable.d,
            R.drawable.e,
    };
    private String[] descs = {
            "AAAAA",
            "BBBBB",
            "CCCCC",
            "DDDDD",
            "EEEEE",
    };

    private LinearLayout ll_dot;
    private TextView viewPager_tv;

    private Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case 1:
                    int currentItem = viewpager_vp.getCurrentItem();
                    viewpager_vp.setCurrentItem(currentItem + 1);
                    sendEmptyMessageDelayed(1, 3000);
                    break;
                default:
                    break;
            }

        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        init();
    }

    private void init() {
        ll_dot = (LinearLayout) findViewById(R.id.ll_dot);
        viewPager_tv = (TextView) findViewById(R.id.ViewPager_tv);

        viewpager_vp = (ViewPager) findViewById(R.id.viewpager_vp);

        for (int x = 0; x < imageResIds.length; x++) {
            ImageView imageView = new ImageView(this);
            imageView.setBackgroundResource(imageResIds[x]);
            ImageViews.add(imageView);
            createDot(x);
        }

        viewpager_vp.setAdapter(new MyViewpagerAdapter(MainActivity.this,ImageViews));

        viewpager_vp.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
                int currentItem = viewpager_vp.getCurrentItem();
                changeTextandDot(currentItem % imageResIds.length);
            }
            @Override
            public void onPageSelected(int position) {

            }
            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });

        viewpager_vp.setCurrentItem(Integer.MAX_VALUE / 2 - 3);

        handler.sendEmptyMessageDelayed(1, 3000);

        ViewPagerTouchEvent();
}

    public void changeTextandDot(int position){
        viewPager_tv.setText(descs[position]);
        for(int x=0; x< imageResIds.length; x++){
            View childAt = ll_dot.getChildAt(x);
            childAt.setBackgroundResource(x==position?R.drawable.dot_focus:R.drawable.dot_normal);
        }

    }

    private void createDot(int x) {
        View view= new View(this);
        view.setBackgroundResource(R.drawable.dot_normal);
        LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(8,8);
        layoutParams.leftMargin=8;
        view.setLayoutParams(layoutParams);
        ll_dot.addView(view);
    }

    public void ViewPagerTouchEvent() {
        viewpager_vp.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View view, MotionEvent motionEvent) {
                switch (motionEvent.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        handler.removeMessages(1);
                        break;
                    case MotionEvent.ACTION_MOVE:
                        handler.removeMessages(1);
                        break;
                    case MotionEvent.ACTION_UP:
                        handler.sendEmptyMessageDelayed(1, 3000);
                    default:
                        break;
                }
                return false;
            }
        });
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();
        handler.removeMessages(1);
    }
}

.MyViewpagerAdapter

package com.example.lunbo;

import android.media.ImageReader;
import android.support.annotation.NonNull;
import android.support.v4.view.PagerAdapter;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

import java.util.ArrayList;

class MyViewpagerAdapter extends PagerAdapter {

    private MainActivity mainActivity;
    private ArrayList<ImageView> imageViews;

    public MyViewpagerAdapter(MainActivity mainActivity, ArrayList<ImageView> imageViews) {
        this.mainActivity = mainActivity;
        this.imageViews = imageViews;
    }

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

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

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

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