Android中fragment+viewpager实现布局

<?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="com.bwei.fragment.MainActivity"> 
 
  <android.support.v4.view.ViewPager 
    android:id="@+id/pager" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" /> 
 
  <RadioGroup 
    android:id="@+id/radioGroup1" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:layout_alignBottom="@+id/pager" 
    android:layout_centerHorizontal="true" 
    android:orientation="horizontal" 
    android:background="#ccc" 
    > 
 
    <RadioButton 
      android:id="@+id/radio0" 
      android:layout_width="0dp" 
      android:layout_height="match_parent" 
      android:checked="true" 
      android:button="@null" 
      android:layout_weight="1" 
      android:text="微信" 
      android:drawableTop="@mipmap/ic_launcher_round" 
      android:gravity="center" 
      /> 
 
    <RadioButton 
      android:id="@+id/radio1" 
      android:layout_width="0dp" 
      android:layout_height="match_parent" 
      android:button="@null" 
      android:layout_weight="1" 
      android:text="通讯录" 
      android:drawableTop="@mipmap/ic_launcher_round" 
      android:gravity="center" 
      /> 
 
    <RadioButton 
      android:id="@+id/radio2" 
      android:layout_width="0dp" 
      android:layout_height="match_parent" 
      android:button="@null" 
      android:layout_weight="1" 
      android:text="发现" 
      android:drawableTop="@mipmap/ic_launcher_round" 
      android:gravity="center" /> 
    <RadioButton 
      android:id="@+id/radio3" 
      android:layout_width="0dp" 
      android:layout_height="wrap_content" 
      android:button="@null" 
      android:layout_weight="1" 
      android:text="我的" 
      android:drawableTop="@mipmap/ic_launcher_round" 
      android:gravity="center"/> 
  </RadioGroup> 
</RelativeLayout> 

public class FragmentThree extends Fragment { 
  @Nullable 
  @Override 
  public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 
     //引入布局文件 
    View view = inflater.inflate(R.layout.fragmentthree, null); 
    return view; 
  } 
} 

<?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"> 
 
 
  <TextView 
    android:id="@+id/textView" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_alignParentTop="true" 
    android:layout_centerHorizontal="true" 
    android:layout_marginTop="230dp" 
    android:text="one" /> 
</RelativeLayout> 

package com.bwei.fragment; 
 
import android.content.Context; 
import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentManager; 
import android.support.v4.app.FragmentPagerAdapter; 
 
import java.util.List; 
 
 
public class MyAdapter extends FragmentPagerAdapter { 
  private List<Fragment> fragments; 
  private Context context; 
  //构造方法 
  public MyAdapter(FragmentManager fm, List<Fragment> fragments, Context context) { 
    super(fm); 
    this.fragments = fragments; 
    this.context = context; 
  } 
  //得到item条目 
  @Override 
  public Fragment getItem(int position) { 
    return fragments.get(position); 
  } 
 
  //得到数量 
  @Override 
  public int getCount() { 
    return fragments.size(); 
  } 
} 

package com.bwei.fragment; 
 
import android.graphics.Color; 
import android.os.Bundle; 
import android.support.annotation.IdRes; 
import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentManager; 
import android.support.v4.view.ViewPager; 
import android.support.v7.app.AppCompatActivity; 
import android.widget.RadioButton; 
import android.widget.RadioGroup; 
import android.widget.Toast; 
 
import java.util.ArrayList; 
import java.util.List; 
 
public class MainActivity extends AppCompatActivity implements RadioGroup.OnCheckedChangeListener,ViewPager.OnPageChangeListener { 
 
  private ViewPager vPager; 
  private List<Fragment> fragments; 
  private FragmentManager fm; 
  private RadioGroup mRadioGroup; 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    //初始化控件 
    initView(); 
    initDate(); 
  } 
 
  private void initView() { 
    vPager=(ViewPager) findViewById(R.id.pager); 
    vPager.setOnPageChangeListener(this); 
    mRadioGroup=(RadioGroup) findViewById(R.id.radioGroup1); 
    mRadioGroup.setOnCheckedChangeListener(this); 
  } 
 
  private void initDate() { 
    fragments=new ArrayList<Fragment>(); 
    //实例化Fragment 
    FragmentOne fragmentOne = new FragmentOne(); 
    FragmentTwo fragmentTwo = new FragmentTwo(); 
    FragmentThree fragmentThree = new FragmentThree(); 
 
    //添加到集合 
    fragments.add(fragmentOne); 
    fragments.add(fragmentTwo); 
    fragments.add(fragmentThree); 
 
    //得到getSupportFragmentManager()的管理器 
    fm = getSupportFragmentManager(); 
    //得到适配器 
    MyAdapter myAdapter = new MyAdapter(fm, fragments, this); 
    //设置适配器 
    vPager.setAdapter(myAdapter); 
  } 
 
  //ViewPager.OnPageChangeListener监听事件 
  @Override 
  public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { 
 
  } 
 
  @Override 
  public void onPageSelected(int position) { 
 
    for (int i = 0; i <fragments.size() ; i++) { 
      RadioButton radiobutton = (RadioButton) mRadioGroup.getChildAt(i); 
      if (i==position) { 
        radiobutton.setChecked(true); 
        //设置选中的颜色 
        radiobutton.setBackgroundColor(Color.RED); 
      }else { 
        radiobutton.setChecked(false); 
        radiobutton.setBackgroundColor(Color.BLACK); 
        radiobutton.setBackgroundColor(Color.BLACK); 
      } 
    } 
  } 
 
  @Override 
  public void onPageScrollStateChanged(int state) { 
 
  } 
 
  //RadioGroup的监听事件 
 
  @Override 
  public void onCheckedChanged(RadioGroup radioGroup, @IdRes int i) { 
 
    for (int j = 0; j <fragments.size() ; j++) { 
      //得到radiobutton 
      RadioButton radiobutton = (RadioButton) mRadioGroup.getChildAt(j); 
      int id = radiobutton.getId(); 
      Toast.makeText(this,id+"", Toast.LENGTH_SHORT).show(); 
      //判断radiobutton的id是否等于选中的id 
      if (radiobutton.getId()==i) { 
        //设置当前页 
        vPager.setCurrentItem(j); 
      } 
    } 
  } 
}