Android控件：RadioButton(单选button)

首先，在布局文件 activity_main.xml中注冊一个RadioGroup,并为RadioGroup设置监听，图中两个RadioButton为一个RadioGroup。

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <TextView android:text="@string/hello_world"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    <RadioGroup
        android:id="@+id/radioGroupID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >

        <RadioButton
            android:id="@+id/femaleGroupID"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="female"
            />
        <RadioButton
            android:id="@+id/maleGroupID"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="male"/>
    </RadioGroup>

</LinearLayout>

MainActivity.java

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.RadioButton;
import android.widget.RadioGroup;

public class MainActivity extends ActionBarActivity {

    private RadioGroup radioGroup;
    private RadioButton femaleRadioButton;
    private RadioButton maleRadioButton;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //载入布局文件
        setContentView(R.layout.activity_main);
        //获取实例
        radioGroup=(RadioGroup)findViewById(R.id.radioGroupID);
        femaleRadioButton=(RadioButton)findViewById(R.id.femaleGroupID);
        maleRadioButton=(RadioButton)findViewById(R.id.maleGroupID);
        //设置监听
        radioGroup.setOnCheckedChangeListener(new RadioGroupListener());
    }
    //定义一个RadioGroup的OnCheckedChangeListener
    //RadioGroup  绑定的是RadioGroup.OnCheckedChangeListener
    //CheckBox    绑定的是CompoundButton.OnCheckedChangeListener 或者 view.OnClickListener

    class RadioGroupListener implements RadioGroup.OnCheckedChangeListener{
        @Override
        public void onCheckedChanged(RadioGroup group, int checkedId) {
            if (checkedId==femaleRadioButton.getId()){
                System.out.println("选中了female!");
            }else if (checkedId==maleRadioButton.getId()){
                System.out.println("选中了male!");
            }
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

日志显演示样例如以下：