RadioGroup与ViewPage联动

在开发中我们常用到RadioGroup与viewpage之间的联动 如以下页面常见的方式

代码如下： MainActivity类

public class MainActivity extends AppCompatActivity implements RadioGroup.OnCheckedChangeListener, ViewPager.OnPageChangeListener {

    private ViewPager mViewPager;
    private RadioGroup mRadioGroup;
    private MainTabAdapter adapter;

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

private void init() {
    mViewPager = (ViewPager) findViewById(R.id.ump_viewpager);
    mRadioGroup = (RadioGroup) findViewById(R.id.rg_ump_layout);
    mRadioGroup.setOnCheckedChangeListener(this);
    mViewPager.setOnPageChangeListener(this);
    adapter = new MainTabAdapter(getSupportFragmentManager(), null);
    mViewPager.setAdapter(adapter);
    mRadioGroup.check(mRadioGroup.getChildAt(0).getId());
    mViewPager.setOffscreenPageLimit(3);
}

@Override
public void onCheckedChanged(RadioGroup radioGroup, @IdRes int i) {
    int index = radioGroup.indexOfChild(radioGroup.findViewById(i));
    mViewPager.setCurrentItem(index);
}

@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

}

/**
 *选择当前position
 *
 */
@Override
public void onPageSelected(int position) {
    View childView = mRadioGroup.getChildAt(position);
    if (childView instanceof RadioButton) {
        RadioButton radioButton = (RadioButton) childView;
        mRadioGroup.check(radioButton.getId());
    }
}

@Override
public void onPageScrollStateChanged(int state) {

    }
}

MainTabAdapter类

class MainTabAdapter extends FragmentPagerAdapter {
    private String[] mTitles = new String[]{"", "", ""};
    private int[] datas = null;

    public MainTabAdapter(FragmentManager fm, int[]     datas) {
        super(fm);

        this.datas = datas;
    }

    @Override
    public Fragment getItem(int position) {
        Fragment fragment = null;
        switch (position) {
            case 0://头条
                fragment = Fragment1.getInstance();
                break;
            case 1://评论
                fragment = Fragment2.getInstance();
                break;
            case 2://论坛
                fragment = Fragment3.getInstance();
                break;

        }

        return fragment;
    }

    @Override
    public int getCount() {
        return mTitles.length;
    }

    @Override
    public CharSequence getPageTitle(int position) {
    return mTitles[position];
    }
}

xml文件如下：activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:app="http://schemas.android.com/apk/res-auto"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:fitsSystemWindows="true"
          android:orientation="vertical">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="54dp"
    android:orientation="horizontal">

    <RadioGroup
        android:id="@+id/rg_ump_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginBottom="10dp"
        android:layout_marginLeft="12dp"
        android:layout_marginRight="12dp"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <RadioButton
            android:id="@+id/rb_ump_Position"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@drawable/rb_bg_posi"
            android:button="@null"
            android:checked="true"
            android:gravity="center"
            android:text="头条"
           android:textColor="@drawable/title_text_sel"
            android:textSize="15sp"/>

        <RadioButton
            android:id="@+id/rb_ump_unFinish"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@drawable/rb_bg_unfini"
            android:button="@null"
            android:gravity="center"
            android:text="评论"
           android:textColor="@drawable/title_text_sel"
            android:textSize="15sp"/>
        <RadioButton
            android:id="@+id/rb_ump_mit"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@drawable/rb_bg_mit"
            android:button="@null"
            android:gravity="center"
            android:text="论坛"
           android:textColor="@drawable/title_text_sel"
            android:textSize="15sp"/>
    </RadioGroup>
</LinearLayout>

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

在res目录的drawable下创建background和字体textColor

效果如下：

下载demo地址RadioGroup与ViewPage联动