activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<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="com.icm.fahd.australia.MainActivity">

    <ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/container_scroll_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <GridLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_alignParentTop="true">

            <ImageButton
                android:id="@+id/imageButton"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="0"
                android:layout_row="0"
                android:onClick="sendMessage"
                android:src="@drawable/perth" />

            <ImageButton
                android:id="@+id/imageButton3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="0"
                android:layout_row="1"
                android:onClick="sendMessageMelbourne"
                android:src="@drawable/melbourne" />

            <ImageButton
                android:id="@+id/imageButton4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="1"
                android:layout_row="1"
                android:onClick="sendMessageDarwin"
                android:src="@drawable/darwin" />

            <ImageButton
                android:id="@+id/imageButton2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="1"
                android:layout_row="0"
                android:onClick="sendMessagesydney"
                android:src="@drawable/sydney" />

            <ImageButton
                android:id="@+id/imageButton5"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="0"
                android:layout_row="2"
                android:onClick="sendMessageCanbera"
                android:src="@drawable/canbera" />

            <ImageButton
                android:id="@+id/imageButton6"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="1"
                android:layout_row="2"
                android:onClick="sendMessageBrisbane"
                android:src="@drawable/brisbane" />


            <ImageButton
                android:id="@+id/wrap"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="0"
                android:layout_row="3"
                android:onClick="sendMessageGoldCoast"
                android:src="@drawable/goldcoast"  />

            <ImageButton
                android:id="@+id/imageButton8"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_column="1"
                android:layout_row="3"
                android:onClick="sendMessageAdelaide"
                android:src="@drawable/adelaide" />



        </GridLayout>
    </ScrollView>
</RelativeLayout>