ViewPager启动页

java代码：

package aa.lin_0805;

import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.Toast;

import java.util.ArrayList;

public class MainActivity extends Activity implements View.OnClickListener, ViewPager.OnPageChangeListener {
    private ViewPager vp;
    private Button bt1;
    private ArrayList<View> views;
    //底部小点的图片
    private ImageView[] points;
    //记录当前选中位置
    private int currentIndex;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        vp = (ViewPager) findViewById(R.id.viewpager_yi);
        views = new ArrayList<>();
        adddata();
        vp.setAdapter(new pageradapter());
        //初始化底部小点
        initPoint(4);
        vp.setOnPageChangeListener(this);

    }

    private void adddata() {
        LayoutInflater lf = LayoutInflater.from(MainActivity.this);
        View v1 = lf.inflate(R.layout.yi_layout, null);
        View v2 = lf.inflate(R.layout.er_layout, null);
        View v3 = lf.inflate(R.layout.san_layout, null);
        View v4 = lf.inflate(R.layout.si_layout, null);
        views.add(v1);
        views.add(v2);
        views.add(v3);
        views.add(v4);
    }


    /**
     * 初始化底部小点
     */
    private void initPoint(int views) {
        LinearLayout linearLayout = (LinearLayout) findViewById(R.id.point);

        points = new ImageView[views];

        //循环取得小点图片
        for (int i = 0; i < views; i++) {
            //得到一个LinearLayout下面的每一个子元素
            points[i] = (ImageView) linearLayout.getChildAt(i);
            //默认都设为灰色
            points[i].setEnabled(true);
            //给每个小点设置监听
            points[i].setOnClickListener(this);
            //设置位置tag，方便取出与当前位置对应
            points[i].setTag(i);
        }

        //设置当面默认的位置
        currentIndex = 0;
        //设置为白色，即选中状态
        points[currentIndex].setEnabled(false);
    }

    @Override
    public void onClick(View v) {

    }


    public class pageradapter extends PagerAdapter {

        //        要滑动视图的数量
        public int getCount() {
            return views.size();
        }

        /**
         * 判断是否由对象生成界面
         * 来判断显示的是否是同一张图片，这里我们将两个参数相比较返回即可
         */
        public boolean isViewFromObject(View view, Object object) {
            return (view == object);
        }

        //        删除多余的，因为viewpager默认缓存是三个视图
        public void destroyItem(ViewGroup container, int position, Object object) {
            //        super.destroyItem(container, position, object);
            container.removeView(views.get(position));
        }


        //        显示的视图
        public Object instantiateItem(ViewGroup container, int position) {
            container.addView(views.get(position), 0);
            return views.get(position);
        }
    }


    /**
     * 当当前页面被滑动时调用
     */
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        System.out.println("onPageScrolled()=>" + position);
    }

    /**
     * 当新的页面被选中时调用
     */
    public void onPageSelected(int position) {
        System.out.println("onPageSelected()=>" + position);
        //设置底部小点选中状态
        setCurDot(position);
    }

    /**
     * 当滑动状态改变时调用
     */
    public void onPageScrollStateChanged(int state) {
        System.out.println("onPageScrollStateChanged()=>" + state);
    }

    /**
     * 设置当前的小点的位置
     */
    private void setCurDot(int positon) {
        if (positon < 0 || positon > 3 || currentIndex == positon) {
            return;
        }
        points[positon].setEnabled(false);
        points[currentIndex].setEnabled(true);

        currentIndex = positon;

        if (positon == 3) {
            bt1 = (Button) findViewById(R.id.bt1);
            bt1.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast.makeText(MainActivity.this, "启动mainactivity", Toast.LENGTH_SHORT).show();
                }
            });
        }
    }


}

XML布局代码：

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


    <android.support.v4.view.ViewPager
        android:id="@+id/viewpager_yi"
        android:layout_width="match_parent"
        android:layout_height="match_parent">


    </android.support.v4.view.ViewPager>

    <LinearLayout
        android:id="@+id/point"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="24.0dip"
        android:orientation="horizontal">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/point" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/point" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/point" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/point" />


    </LinearLayout>
</RelativeLayout>

Selector代码：

<?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/point_normal" />
    <item android:state_enabled="false" android:drawable="@drawable/point_select" />
</selector>