>概念:从多个互斥选项中选择一个 如果是选项全部展开 RadioButton 不是展开的Spinner(下拉列表)
>属性: android:checked="true"
>使用方法:
使用RadioButton要用RadioGroup进行分组 RadioGroup是LinearLayout的子类 可以控制方向
>方式一:使用onclickListner 监听事件(点击事件)
>方式二:****使用OnCheckedChangeListener (RadioGroup) 状态改变的监听 *****
package com.fmy.a;
import android.app.Activity;
import android.os.Bundle;
import android.widget.CompoundButton;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.Toast;
public class MainActivity extends Activity {
private RadioGroup rg;
private RadioButton zrf;
private RadioButton zxc;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.demo_textview);
rg = (RadioGroup) findViewById(R.id.rg);
zrf = (RadioButton) findViewById(R.id.zrf);
zxc = (RadioButton) findViewById(R.id.zxc);
zxc.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override //buttonView就是RadioButton对象 isChecked对象是否本选中
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
Toast.makeText(MainActivity.this, "嘿嘿"+buttonView.getText().toString(), 3).show();
}
});
rg.setOnCheckedChangeListener(new OnCheckedChangeListener() {
//rg本身的对象 checkedId 状态被改变子id
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
RadioButton rb =(RadioButton) findViewById(checkedId);
Toast.makeText(MainActivity.this, "哈哈"+rb.getText().toString(), 3).show();
}
});
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<RadioGroup
android:id="@+id/rg"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<!-- android:checked="true" 设置默认选中-->
<RadioButton
android:id="@+id/zrf"
android:checked="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="周润发" />
<RadioButton
android:id="@+id/zxc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="周星驰" />
</RadioGroup>
</LinearLayout>