Radio button RadioButton is also widely used on the Android platform. For example, when selecting items, radio buttons are used. The radio button consists of two parts, that is, RadioButton and RadioGroup are used together.
RadioButton's radio button;
RadioGroup is a radio button combo box, used to frame RadioButton;
In the absence of RadioGroup, all RadioButtons can be selected ;
When multiple RadioButtons are included in a RadioGroup, only one RadioButton can be selected;
Note: The event monitoring of the radio button uses setOnCheckedChangeListener to monitor the radio button
Example:
A multiple-choice question, choose which city has the most beauties. Of course, this is for testing
RadioTest.java
package org.loulijun.radio; import android.app.Activity; import android.os.Bundle; import android.view.Gravity; import android.widget.RadioButton; import android.widget.RadioGroup; import android.widget.TextView; import android.widget.Toast; public class RadioTest extends Activity { /** Called when the activity is first created. */ TextView textview; RadioGroup radiogroup; RadioButton radio1,radio2,radio3,radio4; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); textview=(TextView)findViewById(R.id.textview1); radiogroup=(RadioGroup)findViewById(R.id.radiogroup1); radio1=(RadioButton)findViewById(R.id.radiobutton1); radio2=(RadioButton)findViewById(R.id.radiobutton2); radio3=(RadioButton)findViewById(R.id.radiobutton3); radio4=(RadioButton)findViewById(R.id.radiobutton4); radiogroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() { @Override public void onCheckedChanged(RadioGroup group, int checkedId) { // TODO Auto-generated method stub if(checkedId==radio2.getId()) { DisplayToast("正确答案:"+radio2.getText()+",恭喜你,回答正确!"); }else { DisplayToast("请注意,回答错误!"); } } }); } public void DisplayToast(String str) { Toast toast=Toast.makeText(this, str, Toast.LENGTH_LONG); toast.setGravity(Gravity.TOP,0,220); toast.show(); } }
strings.xml file
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello">哪个城市美女多?</string> <string name="app_name">单选按钮测试</string> <string name="radiobutton1">杭州</string> <string name="radiobutton2">成都</string> <string name="radiobutton3">重庆</string> <string name="radiobutton4">苏州</string> </resources>
main.xml file: Note that here, 4 RadioButtons are included in RadioGroup
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" android:id="@+id/textview1" /> <RadioGroup android:id="@+id/radiogroup1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="vertical" android:layout_x="3px" > <RadioButton android:id="@+id/radiobutton1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/radiobutton1" /> <RadioButton android:id="@+id/radiobutton2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/radiobutton2" /> <RadioButton android:id="@+id/radiobutton3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/radiobutton3" /> <RadioButton android:id="@+id/radiobutton4" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/radiobutton4" /> </RadioGroup> </LinearLayout>
The running results are as follows:
If we choose Hangzhou, the wrong Toast will be prompted
After selecting Chengdu again, the correct answer will be prompted
Here you can see the effect of using radio buttons. If you only use RadioButton, remove the RadioGroup in the configuration file. Of course, you must re-set the monitoring for each radio button. In this way, this RadioButton is no different from Button. We can select multiple, so it should be noted that the radio button must be used together with the RadioGroup to achieve the radio selection function.
The above is the content of the Android UI control series: RadioButton (radio button). For more related content, please pay attention to the PHP Chinese website (www.php.cn)!

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