title: I would like to ask your a button in the different layout
body: <p>Excuse my English is not good, I would ask why the button in the RelativeLayout is gray in the press, the LinearLayout is no problem</p>
  
  <pre><code>&lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:paddingBottom="@dimen/activity_vertical_margin"
      android:paddingLeft="@dimen/activity_horizontal_margin"
      android:paddingRight="@dimen/activity_horizontal_margin"
      android:paddingTop="@dimen/activity_vertical_margin"
      tools:context=".MainActivity" &gt;
  
      &lt;Button
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:onClick="add"
          android:text="button" /&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>