title: Buttons inside Table layout not showing up in emulator
body: <p>I have made a simple table layout with buttons. When I try to run it , the emulator doesn't show anything, only a spot! does to anyone happened this problem again?</p>
  <p>L<strong>ayout file</strong></p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
  &lt;TableLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
   android:gravity=&quot;center&quot;
   xmlns:app=&quot;http://schemas.android.com/apk/res-auto&quot;
   xmlns:tools=&quot;http://schemas.android.com/tools&quot; android:layout_width=&quot;match_parent&quot;
   android:layout_height=&quot;match_parent&quot;
   tools:context=&quot;.MainActivity&quot;&gt;
  
  &lt;TableRow
      android:layout_marginBottom=&quot;3pt&quot;
      android:gravity=&quot;center&quot;
      android:layout_width=&quot;match_parent&quot;
      android:layout_height=&quot;match_parent&quot; &gt;
  
      &lt;com.google.android.material.button.MaterialButton
          android:background=&quot;@color/white&quot;
          android:id=&quot;@+id/bu1&quot;
          android:layout_width=&quot;40pt&quot;
          android:layout_height=&quot;40pt&quot;
          android:layout_marginEnd=&quot;3pt&quot;
          android:onClick=&quot;buClick&quot; /&gt;
  
      &lt;com.google.android.material.button.MaterialButton
          android:background=&quot;@color/white&quot;
          android:id=&quot;@+id/bu2&quot;
          android:layout_width=&quot;40pt&quot;
          android:layout_height=&quot;40pt&quot;
          android:layout_marginEnd=&quot;3pt&quot;
          android:onClick=&quot;buClick&quot; /&gt;
  
      &lt;com.google.android.material.button.MaterialButton
          android:background=&quot;@color/white&quot;
          android:id=&quot;@+id/bu3&quot;
          android:layout_width=&quot;40pt&quot;
          android:layout_height=&quot;40pt&quot;
          android:onClick=&quot;buClick&quot; /&gt;
  &lt;/TableRow&gt;
  
  &lt;TableRow
      android:layout_marginBottom=&quot;3pt&quot;
      android:gravity=&quot;center&quot;
      android:layout_width=&quot;match_parent&quot;
      android:layout_height=&quot;match_parent&quot; &gt;
  
      &lt;com.google.android.material.button.MaterialButton
          android:background=&quot;@color/white&quot;
          android:id=&quot;@+id/bu4&quot;
          android:layout_width=&quot;40pt&quot;
          android:layout_height=&quot;40pt&quot;
          android:layout_marginEnd=&quot;3pt&quot;
          android:onClick=&quot;buClick&quot; /&gt;
  
      &lt;com.google.android.material.button.MaterialButton
          android:background=&quot;@color/white&quot;
          android:id=&quot;@+id/bu5&quot;
          android:layout_width=&quot;40pt&quot;
          android:layout_height=&quot;40pt&quot;
          android:layout_marginEnd=&quot;3pt&quot;
          android:onClick=&quot;buClick&quot; /&gt;
  
      &lt;com.google.android.material.button.MaterialButton
          android:background=&quot;@color/white&quot;
          android:id=&quot;@+id/bu6&quot;
          android:layout_width=&quot;40pt&quot;
          android:layout_height=&quot;40pt&quot;
          android:onClick=&quot;buClick&quot; /&gt;
   &lt;/TableRow&gt;   
  &lt;/TableLayout&gt;
  </code></pre>
  <p>and the preview is: <a href="https://i.stack.imgur.com/4pUaa.png" rel="nofollow noreferrer">preview</a></p>
  <p>what I did wrong? do I have to do something else? because I try everything</p>