title: How can i visibility to true in android studio?
body: <p>I have a problem,i write this in my activity xml file:<br/></p>
  
  <pre><code>&lt;fragment
              android:id="@+id/map"
              android:name="com.google.android.gms.maps.MapFragment"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              xmlns:android="http://schemas.android.com/apk/res/android"
              android:visibility="invisible"  /&gt;
  </code></pre>
  
  <p>i want when i click in button my fragment visibile to true.How can i do this?
  i want set visible in java class code,into button click event.</p>