itcs4180/HW4/res/layout/activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/layout_async"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    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" >

    <GridView
        android:id="@+id/grid_async"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:columnWidth="90dp"
        android:numColumns="@integer/column_count" />
    
    <Button
        android:id="@+id/btn_exit_async"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:text="@string/exit_button_text" />

</LinearLayout>