title: Why GridLayout doesn't fill all the available space?
body: <p>I have a GridLayout (to which I add the children programmatically).</p>
  
  <p>The result is ugly because the GridLayout doesn't fill all the available space.</p>
  
  <p>This is the outcome:</p>
  
  <p><img src="https://i.stack.imgur.com/6FxdD.png" alt="enter image description here"></p>
  
  <p>this is my XML:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
   &gt;
  
  &lt;HorizontalScrollView
      android:layout_width="match_parent"
      android:layout_height="match_parent" &gt;
  
      &lt;android.support.v7.widget.GridLayout
          android:id="@+id/gridlayout"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:background="@android:color/white" &gt;
      &lt;/android.support.v7.widget.GridLayout&gt;
  &lt;/HorizontalScrollView&gt;
  
  &lt;/ScrollView&gt;
  </code></pre>