Android ViewPager+Fragment(碎片)实现页面滑动

效果图：

既可以实现滑动使单选按钮改变颜色，也可以通过点击单选按钮实现页面跳转，类似于微信

xml代码(布局文件)：

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"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_height="match_parent" tools:context="com.example.test0615.MainActivity">

    <android.support.v4.view.ViewPager
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:id="@+id/vp_main_viewpager"
        ></android.support.v4.view.ViewPager>
    <RadioGroup
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:id="@+id/rg_main_radio"
        >
        <!--layout_weight属性：设置权重，每个单选按钮占屏幕宽度的四分之一；button属性：设置单选按钮不可见-->
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:button="@null"
            android:text="微信"
            android:id="@+id/rb_mian_one"
            android:layout_weight="1"
            android:background="@drawable/selector_radiobutton"
            />
        <!--background属性：设置单选按钮的选择器-->
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:button="@null"
            android:text="通讯录"
            android:id="@+id/rb_mian_two"
            android:layout_weight="1"
            android:background="@drawable/selector_radiobutton"
            />
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:button="@null"
            android:text="发现"
            android:id="@+id/rb_mian_three"
            android:layout_weight="1"
            android:background="@drawable/selector_radiobutton"
            />
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:button="@null"
            android:text="我"
            android:id="@+id/rb_mian_four"
            android:layout_weight="1"
            android:background="@drawable/selector_radiobutton"
            />
    </RadioGroup>

</LinearLayout>

选择器代码:

selcctor_radiobutton:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_checked="true" android:drawable="@color/colorPrimary"></item>//单选按钮被选中，背景颜色为蓝色
    <item android:state_checked="false" android:drawable="@color/colorAccent"></item>//为被选中，背景颜色为粉色
</selector>

页面代码：

 fragment_weixin.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="这是微信页面"
        android:textSize="40sp"
        />
</LinearLayout>

fragment_contacts.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="这是通讯录页面"
        android:textSize="40sp"
        />
</LinearLayout>

同样的页面，我们在写两个，在这里我就不再写了

接下来我们就是将页面转为Fragment了

WeiXinFragment.java

package com.example.test0615;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

/**
 * Created by Administrator on 2017/6/15 0015.
 */

public class WeiXinFragment extends Fragment {
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_weixin,null);//方法的第一个参数为我们需要转化的页面
    }
}

ContactsFragment.java

package com.example.test0615;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

/**
 * Created by Administrator on 2017/6/15 0015.
 */

public class ContactsFragment extends Fragment {
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_contacts,null);
    }
}

再建两个Java页面，将剩下的两个个页面转为Fragment

接下来就是代码的重中之重：

package com.example.test0615;

import android.support.annotation.IdRes;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.RadioButton;
import android.widget.RadioGroup;

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

public class MainActivity extends AppCompatActivity {

    private ViewPager vp_main_viewpager;
    private RadioGroup rg_main_radio;
    //定义一个用来放Fragment的集合
    private List<Fragment> fragments=new ArrayList<>();
    //用来放View的集合
    private List<View> buttons;

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

        vp_main_viewpager = (ViewPager) findViewById(R.id.vp_main_viewpager);
        rg_main_radio = (RadioGroup) findViewById(R.id.rg_main_radio);

        WeiXinFragment weiXinFragment=new WeiXinFragment();
        ContactsFragment contactsFragment=new ContactsFragment();
        FindFragment findFragment=new FindFragment();
        MyFragment myFragment=new MyFragment();
        
        //将Fragment放入集合
        fragments.add(weiXinFragment);
        fragments.add(contactsFragment);
        fragments.add(findFragment);
        fragments.add(myFragment);

        //设置适配器
        vp_main_viewpager.setAdapter(new MyAdapter(getSupportFragmentManager()));

        //得到单选组的所有单选按钮
        buttons=rg_main_radio.getTouchables();

        //给页面设置一个监听事件
        vp_main_viewpager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            //页面滑动事件
            @Override
            public void onPageSelected(int position) {
                //根据页面的位置拿到每个页面对应的单选按钮
                RadioButton radioButton= (RadioButton) buttons.get(position);
                //将该单选按钮设置为选中状态
                radioButton.setChecked(true);
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
        
        //给单选组设置点击事件监听
        rg_main_radio.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
                //如果当前单选按钮的ID为自己设置的ID
                if(checkedId==R.id.rb_mian_one){
                    //设置当前展示的页面
                    vp_main_viewpager.setCurrentItem(0);
                }else if(checkedId==R.id.rb_mian_two){
                    vp_main_viewpager.setCurrentItem(1);
                }else if(checkedId==R.id.rb_mian_three){
                    vp_main_viewpager.setCurrentItem(2);
                }else if(checkedId==R.id.rb_mian_four){
                    vp_main_viewpager.setCurrentItem(3);
                }
            }
        });
    }

    class MyAdapter extends FragmentPagerAdapter{

        public MyAdapter(FragmentManager fm) {
            super(fm);
        }

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

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