title: Relativelayout align top and bottom
body: <p>I would like to align center horizontial &amp; center vertical all 3 buttons as 1 button in my relativelayout!</p>
  
  <p>I used LinearLayout with parameter android:layout_weight, but Buttons's height is modified.
  This is my layout file. Thanks!</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=".Main" &gt;
  
  &lt;Button
      android:id="@+id/bt_singleColor"
      android:layout_width="150dp"
      android:layout_height="100dp"
      android:layout_centerHorizontal="true"
      android:layout_margin="@dimen/button_margin"
      android:background="@drawable/button_circle"
      android:padding="@dimen/button_padding"
      android:text="@string/button_01"
      android:textColor="@color/button_text_color" /&gt;
  
  &lt;Button
      android:id="@+id/bt_shake"
      android:layout_width="150dp"
      android:layout_height="100dp"
      android:layout_below="@+id/bt_singleColor"
      android:layout_centerHorizontal="true"
      android:layout_margin="@dimen/button_margin"
      android:background="@drawable/button_circle"
      android:padding="@dimen/button_padding"
      android:text="@string/button_02"
      android:textColor="@color/button_text_color" /&gt;
  
  &lt;Button
      android:id="@+id/bt_autoColor"
      android:layout_width="150dp"
      android:layout_height="100dp"
      android:layout_below="@+id/bt_shake"
      android:layout_centerHorizontal="true"
      android:layout_margin="@dimen/button_margin"
      android:background="@drawable/button_circle"
      android:padding="@dimen/button_padding"
      android:text="@string/button_03"
      android:textColor="@color/button_text_color" /&gt;
  </code></pre>
  
  <p></p>