android开发之浅谈viewpager

<?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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.example.liberty.androidclick.MainActivity"
    tools:showIn="@layout/activity_main"
    android:orientation="vertical">
    <android.support.design.widget.TabLayout
        android:id="@+id/tab"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
    
    <android.support.v4.view.ViewPager
        android:id="@+id/viewpager"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
    <!--这是第一步 在布局文件里加入android.support.v4.view.ViewPager-->
</RelativeLayout>

package com.example.liberty.androidclick;

import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

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

public class MainActivity extends AppCompatActivity {
    private ViewPager mViewPager;
    private TabLayout mTabLayout;
    private LayoutInflater mInflater;
    private List<String>mTitleList= new ArrayList<>();
    private View view1,view2,view3,view4;
    private List<View>mViewList= new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mViewPager = (ViewPager)findViewById( R.id.viewpager);
         mTabLayout = (TabLayout) findViewById(R.id.tab);
        mInflater = LayoutInflater.from(this);
        view1 = mInflater.inflate(R.layout.layout1,null);
        view2 = mInflater.inflate(R.layout.content_main,null);
        view3 = mInflater.inflate(R.layout.content_main,null);
        view4 = mInflater.inflate(R.layout.content_main,null);
        mViewList.add(view1);
        mViewList.add(view2);
        mViewList.add(view3);
        mViewList.add(view4);
//这是第二步 实例化viewpager加载要显示的布局
        mTitleList.add("No:1");
        mTitleList.add("No:2");
        mTitleList.add("No:3");
        mTitleList.add("No:4");

        mTabLayout.setTabMode(TabLayout.MODE_FIXED);
        mTabLayout.addTab(mTabLayout.newTab().setText(mTitleList.get(0)));
        mTabLayout.addTab(mTabLayout.newTab().setText(mTitleList.get(1)));
        mTabLayout.addTab(mTabLayout.newTab().setText(mTitleList.get(2)));
        mTabLayout.addTab(mTabLayout.newTab().setText(mTitleList.get(3)));

        MyPagerAdapter mAdapter = new MyPagerAdapter(mViewList);
        mViewPager.setAdapter(mAdapter);
//        设置mAdapter
        mTabLayout.setupWithViewPager(mViewPager);
        mTabLayout.setTabsFromPagerAdapter(mAdapter);
    }
      class MyPagerAdapter extends PagerAdapter {
          private List<View> mViewList;
        public MyPagerAdapter(List<View> mViewList) {
            this.mViewList = mViewList;
        }
//         这是第三步 重写PagerAdapter

        @Override
        public int getCount() {
            return mViewList.size();//页卡数
        }
          @Override
          public Object instantiateItem(ViewGroup container, int position) {
              container.addView(mViewList.get(position));//添加页卡
              return mViewList.get(position);
          }

          @Override
          public void destroyItem(ViewGroup container, int position, Object object) {
              container.removeView(mViewList.get(position));//删除页卡
          }

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

          @Override
          public CharSequence getPageTitle(int position) {
              return mTitleList.get(position);//页卡标题
          }

    }
}