使用RadioButton+Fragment实现底部导航栏效果

底部导航栏，在我们App项目中是非常常用！而且实现它的方式很多，今天我们就来使用RadioButton+Fragment实现底部导航栏！

下面就让我们动手吧，首先我们打开RadioButtonDemo这个项目，首先修改activity_main.xml文件如下:

<?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>

这里我们在布局文件Fragment控件:用于显示界面的切换。

RadioGroup控件包含了4个RadioButton:用于显示按钮。我们给第一个按钮check为true默认选中。其中android:button=”@null” 取消圆点。

drawableTop属性:

<?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>

显示选择和未选中的状态的图标

创建Fragment，加载Fragment布局文件，类代码如下:

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);
}
}

接下来我们来修改MainActivity.class中的代码，在这里实现点击按钮切换Fragment的具体功能，代码如下:

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;
}
}

好了，这样的话，所有的代码就已经完成了，可以运行一下看看完整的效果了最终效果图: