title: android unchecked radio button which is already checked
body: <pre><code>&lt;RadioGroup xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/rg"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:context="com.example.radiogroup.MainActivity" &gt;
  
      &lt;RadioButton
          android:id="@+id/rb_true"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_weight="1"
          android:gravity="center_vertical" /&gt;
  
      &lt;RadioButton
          android:id="@+id/rb_false"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_weight="1"
          android:gravity="center_vertical" /&gt;
  
  &lt;/RadioGroup&gt;
  </code></pre>
  
  <p>i have one radio group
  in which i have 2 radio button </p>
  
  <p>now if radio button 1 is selected and if i tap on same radio button(radio button 1) it should be unchecked ..</p>
  
  <p>it should work as<strong>toggle</strong>.</p>