【RadioGroup】实现单选并获得所选项值

Android RadioGroup有时候很有用，给用户提供多选一机制，现在要绘制一个画面，事例如下：

上面是一个TextView，下面有个RadioGroup，布局如下：

mian.xml

主控制程序 RadioGroupDemo.java：

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package com.android.test;
 
import android.app.Activity;
import android.os.Bundle;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
 
public class RadioGroupDemo extends Activity {
    public TextView mTextView1;
    public RadioGroup mRadioGroup1;
    public RadioButton mRadio1, mRadio2;
 
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
 
        // 取得 TextView、RadioGroup、RadioButton对象
        mTextView1 = (TextView) findViewById(R.id.myTextView);
        mRadioGroup1 = (RadioGroup) findViewById(R.id.myRadioGroup);
        mRadio1 = (RadioButton) findViewById(R.id.myRadioButton1);
        mRadio2 = (RadioButton) findViewById(R.id.myRadioButton2);
 
        // RadioGroup用OnCheckedChangeListener来运行
        mRadioGroup1.setOnCheckedChangeListener(mChangeRadio);
    }
 
    private RadioGroup.OnCheckedChangeListener mChangeRadio = new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup group, int checkedId) {
            // TODO Auto-generated method stub
            if (checkedId == mRadio1.getId()) {
                // 把mRadio1的内容传到mTextView1
                mTextView1.setText(mRadio1.getText());
            } else if (checkedId == mRadio2.getId()) {
                // 把mRadio2的内容传到mTextView1
                mTextView1.setText(mRadio2.getText());
            }
        }
    };
}

需要注意的就是RadioGroup的消息处理。
mRadioGroup1.setOnCheckedChangeListener(mChangeRadio);