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    Selecting Female & pushing DISPLAY ⇒  | 
  
    
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RadioButton in your layout.
However, because radio buttons are mutually exclusive, you must group them together inside a RadioGroup. 
By grouping them together, the system ensures that only one radio button can be selected at a time.
RadioButton object receives an on-click event.
To define the click event handler for a button, add the android:onClick attribute to the RadioButton element in your XML layout.
The value for this attribute must be the name of the method you want to call in response to a click event.
The activity hosting the layout must then implement the corresponding method.
However, this example uses another approach.
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<?xml version="1.0" encoding="utf-8"?>
<manifest
  xmlns:android = "http://schemas.android.com/apk/res/android"
  package       = "com.example.wenchen.myapplication">
  <application
    android:icon  = "@mipmap/ic_launcher"
    android:label = "@string/app_name"
    android:theme = "@style/AppTheme">
    <activity
      android:name  = ".MainActivity"
      android:label = "@string/app_name">
      <intent-filter>
        <action   android:name = "android.intent.action.MAIN" />
        <category android:name = "android.intent.category.LAUNCHER" />
      </intent-filter>
    </activity>
  </application>
</manifest>
    
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     Prince, what you are you are by accident of birth;      what I am I am through myself. There have been and still will be thousands of princes; there is only one Beethoven. – Ludwig van Beethoven  |