Android RelativeLayout : how to alignParentBottom when wrapped in a ScrollView?

Question

The problem I am having seems to be that if I have a view (e.g. myButton) inside a RelativeLayout set to alignParentBottom - (as per the code below) - and then wrap the RelativeLayout with a scrollview (necessary so the content will be viewable on smaller screens or when orientation changes to landscape) - then, when the parent bottom is NOT visible (for example when changed to landscape orientation) myButton is displayed at the TOP of the page - NOT the bottom.

How can you align a view to the bottom of the screen and have it remain at the bottom even if the bottom is below the scroll?

<ScrollView
android:id="@+id/mainScrollView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
android:fillViewport="true">



<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:id="@+id/topLayout"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent">



... lots of views and stuff


<Button android:layout_alignParentBottom="true" 
android:id="@+id/myButton"  
android:text="Click Me" />

</RelativeLayout>
</ScrollView>   

Answer 1

Using fill_parent as the height of a child of a ScrollView is meaningless. You are telling the RelativeLayout to be always as tall as its parent. In this case, the ScrollView becomes useless! The height of the RelativeLayout should be set to wrap_content, in which case, depending on what the RelativeLayout contains, alignParentBottom may not work as you expect. You should simply use a LinearLayout, it will be much much simpler.