黑马程序员——Android之重要组件ButtonGroup

package com.example.buttongroup;

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

public class MainActivity extends Activity {
TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv=(TextView) findViewById(R.id.tv);
RadioGroup group=(RadioGroup)findViewById(R.id.radioGroup1);
group.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
//绑定一个匿名监听器
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
// TODO Auto-generated method stub
int radioButtonId=group.getCheckedRadioButtonId();
RadioButton rb=(RadioButton) MainActivity.this.findViewById(radioButtonId);
tv.setText("您的性别时："+rb.getText());
}
});
}

}

<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" >

<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="请选择您的性别"
android:textSize="9pt" />

<RadioGroup
android:id="@+id/radioGroup1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >

<RadioButton
android:id="@+id/radio0"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:checked="true"
android:text="男" />

<RadioButton
android:id="@+id/radio1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="女" />

</RadioGroup>
<TextView
android:id="@+id/tv"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="您的性别是,男"
android:textSize="9pt" />

</LinearLayout>