<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/container"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:gravity="center"
      android:orientation="vertical" >
  
      <Button
          android:id="@+id/send"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="Mark an event" />
  
      <Button
          android:id="@+id/upgrade"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="Level upgrade" />
  
      <Button
          android:id="@+id/purchase"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="Purchase" />
  
  </LinearLayout>