使用RadioButton+Fragment实现底部导航栏效果

<?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:layout_height="match_parent"
 android:orientation="vertical"
 tools:context="com.example.jackhu.radiobuttondemo.MainActivity">

 <FrameLayout
  android:id="@+id/mFragment"
  android:layout_width="match_parent"
  android:layout_height="0dp"
  android:layout_weight="1"></FrameLayout>

 <RadioGroup
  android:layout_marginBottom="2dp"
  android:id="@+id/mRadioGroup"
  android:orientation="horizontal"
  android:layout_width="match_parent"
  android:layout_height="48dp">
  <RadioButton
   android:drawableTop="@drawable/rbhome"
   android:button="@null"
   android:checked="true"
   android:textColor="@color/colorRadioButtonP"
   android:id="@+id/mRb_home"
   android:gravity="center"
   android:layout_width="0dp"
   android:text="Home"
   android:layout_weight="1"
   android:layout_height="match_parent" />

  <RadioButton
   android:drawableTop="@drawable/rb_message"
   android:button="@null"
   android:textColor="@color/colorRadioButtonN"
   android:id="@+id/mRb_message"
   android:gravity="center"
   android:layout_width="0dp"
   android:text="Message"
   android:layout_weight="1"
   android:layout_height="match_parent" />

  <RadioButton
   android:drawableTop="@drawable/rbfind"
   android:button="@null"
   android:textColor="@color/colorRadioButtonN"
   android:id="@+id/mRb_find"
   android:gravity="center"
   android:layout_width="0dp"
   android:text="Find"
   android:layout_weight="1"
   android:layout_height="match_parent" />

  <RadioButton
   android:drawableTop="@drawable/rbmy"
   android:button="@null"
   android:textColor="@color/colorRadioButtonN"
   android:id="@+id/mRb_my"
   android:gravity="center"
   android:layout_width="0dp"
   android:text="My"
   android:layout_weight="1"
   android:layout_height="match_parent" />

 </RadioGroup>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
 <item android:state_checked="true" android:drawable="@drawable/home_p"/>
 <item android:drawable="@drawable/home_n"/>
</selector>

package com.example.jackhu.radiobuttondemo.fragment;


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

import com.example.jackhu.radiobuttondemo.R;

/**
 * A simple {@link Fragment} subclass.
 */
public class HomeFragment extends Fragment {


 public HomeFragment() {
  // Required empty public constructor
 }

 //单例模式
 public static HomeFragment newInstance(){
  HomeFragment homeFragment=new HomeFragment();
  return homeFragment;
 }

 @Override
 public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
  // Inflate the layout for this fragment
  return inflater.inflate(R.layout.fragment_home, container, false);
 }

}

package com.example.jackhu.radiobuttondemo;

import android.support.annotation.IdRes;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;

import com.example.jackhu.radiobuttondemo.fragment.FindFragment;
import com.example.jackhu.radiobuttondemo.fragment.HomeFragment;
import com.example.jackhu.radiobuttondemo.fragment.MessageFragment;
import com.example.jackhu.radiobuttondemo.fragment.MyFragment;

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

public class MainActivity extends AppCompatActivity implements RadioGroup.OnCheckedChangeListener {

 private RadioGroup mRadioGroup;
 private List<Fragment> fragments = new ArrayList<>();
 private Fragment fragment;
 private FragmentManager fm;
 private FragmentTransaction transaction;
 private RadioButton rb_Home,rb_Message,rb_Find,rb_My;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  initView(); //初始化组件
  mRadioGroup.setOnCheckedChangeListener(this); //点击事件
  fragments = getFragments(); //添加布局
  //添加默认布局
  normalFragment();
 }

 //默认布局
 private void normalFragment() {
  fm=getSupportFragmentManager();
  transaction=fm.beginTransaction();
  fragment=fragments.get(0);
  transaction.replace(R.id.mFragment,fragment);
  transaction.commit();
 }

 private void initView() {
  mRadioGroup = (RadioGroup) findViewById(R.id.mRadioGroup);
  rb_Home= (RadioButton) findViewById(R.id.mRb_home);
  rb_Message= (RadioButton) findViewById(R.id.mRb_message);
  rb_Find= (RadioButton) findViewById(R.id.mRb_find);
  rb_My= (RadioButton) findViewById(R.id.mRb_my);
 }

 @Override
 public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
  fm=getSupportFragmentManager();
  transaction=fm.beginTransaction();
  switch (checkedId){
   case R.id.mRb_home:
    fragment=fragments.get(0);
    transaction.replace(R.id.mFragment,fragment);
    Toast.makeText(this, "Home", Toast.LENGTH_SHORT).show();
    break;
   case R.id.mRb_message:
    fragment=fragments.get(1);
    transaction.replace(R.id.mFragment,fragment);
    Toast.makeText(this, "Message", Toast.LENGTH_SHORT).show();
    break;
   case R.id.mRb_find:
    fragment=fragments.get(2);
    transaction.replace(R.id.mFragment,fragment);
    Toast.makeText(this, "Find", Toast.LENGTH_SHORT).show();
    break;
   case R.id.mRb_my:
    fragment=fragments.get(3);
    transaction.replace(R.id.mFragment,fragment);
    Toast.makeText(this, "My", Toast.LENGTH_SHORT).show();
    break;
  }
  setTabState();
  transaction.commit();
 }

 //设置选中和未选择的状态
 private void setTabState() {
  setHomeState();
  setMessageState();
  setFindState();
  setMyState();
 }

 private void setMyState() {
  if (rb_My.isChecked()){
   rb_My.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonP));
  }else{
   rb_My.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonN));
  }
 }

 private void setFindState() {
  if (rb_Find.isChecked()){
   rb_Find.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonP));
  }else{
   rb_Find.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonN));
  }
 }

 private void setMessageState() {
  if (rb_Message.isChecked()){
   rb_Message.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonP));
  }else{
   rb_Message.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonN));
  }
 }

 private void setHomeState() {
  if (rb_Home.isChecked()){
   rb_Home.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonP));
  }else{
   rb_Home.setTextColor(ContextCompat.getColor(this,R.color.colorRadioButtonN));
  }
 }

 public List<Fragment> getFragments() {
  fragments.add(new HomeFragment());
  fragments.add(new MessageFragment());
  fragments.add(new FindFragment());
  fragments.add(new MyFragment());
  return fragments;
 }
}