ViewPager,RadioGroup,FragmentManager 详解 <四> Fragment，ViewPager 和TabLayout

这个TabLayout和PagerTabStrip类似，区别在于：

0：布局不同,这个TabLayout 是在ViewPager 的外面,而且是上面.
1：注意这个TabLayout 是design 包里面的.
2：最关键的一个代码就是,而且这个要在设置完了adapter 之后再执行.
 tabLayout.setupWithViewPager(mComicViewPager);

0：创建Fragment

1：创建布局，注意布局里面TabLayout 不是在ViewPager 里面，而是在ViewPager的上面，还有TabLayout 是design 包里面的，所以要引入design的包

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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" android:paddingLeft="@dimen/activity_horizontal_margin"  android:paddingRight="@dimen/activity_horizontal_margin"  android:paddingTop="@dimen/activity_vertical_margin"  android:orientation="vertical"  android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

    <android.support.design.widget.TabLayout  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:id="@+id/tablayout"  >
    </android.support.design.widget.TabLayout>
    <android.support.v4.view.ViewPager  android:layout_width="match_parent"  android:layout_height="0dp"  android:layout_weight="1"  android:id="@+id/viewPager"></android.support.v4.view.ViewPager>

</LinearLayout>

2：然后设置adapter，

这个adapter 和使用PagerTabStrip 的时候是一样的。都是在getPagerTitle 里面进行Tab的标题的设置。

package tech.androidstudio.tablayoutviewpagerdemo.adapter;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;

import java.util.List;

/**  * Created by Kodulf on 2016/3/14.  */ public class TabLayoutFragmentPagerAdapter extends FragmentPagerAdapter {
    List<Fragment> list;

    public TabLayoutFragmentPagerAdapter(FragmentManager fm, List<Fragment> list) {
        super(fm);
        this.list = list;
    }

    @Override
    public Fragment getItem(int position) {
        return list.get(position);
    }

    @Override
    public int getCount() {
        return list.size();
    }

    @Override
    public CharSequence getPageTitle(int position) {
// return super.getPageTitle(position);  String ret;
        switch (position){
            case 0:
                ret="财经";
                break;
            case 1:
                ret="体育";
                break;
            case 2:
                ret="娱乐";
                break;
            default:
                ret="未命名";
                break;
        }
        return ret;
    }
}

3：MainActivity

最关键的一个代码就是,而且这个要在设置完了adapter 之后再执行.
 tabLayout.setupWithViewPager(mComicViewPager);

package tech.androidstudio.tablayoutviewpagerdemo;

import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

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

import tech.androidstudio.tablayoutviewpagerdemo.adapter.TabLayoutFragmentPagerAdapter;

public class MainActivity extends AppCompatActivity {

    private TabLayout mTabLayout;
    private ViewPager mViewPager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mTabLayout = (TabLayout)findViewById(R.id.tablayout);
        mViewPager = (ViewPager)findViewById(R.id.viewPager);

        List<Fragment> mList = new ArrayList<Fragment>();
        mList.add(new FirstFragment());
        mList.add(new SecondFragment());
        mList.add(new ThirdFragment());

        TabLayoutFragmentPagerAdapter adapter = new TabLayoutFragmentPagerAdapter(getSupportFragmentManager(),mList);
        
        //一定要先设置adapter ，然后在使用命令mTabLayout.setupWithViewPager(mViewPager);  mViewPager.setAdapter(adapter);
        //这一步是最关键，将tablayout 和viewpager 连接起来了  mTabLayout.setupWithViewPager(mViewPager);


    }
}