Right-aligning button in a grid with possibly no content - stretch grid to always fill the page

I am losing my patience with this. I am working on a Windows Phone 7 application and I can't figure out what layout manager to use to achieve the following:

Basically, when I use a Grid as the layout root, I can't make the grid to stretch to the size of the phone application page. When the main content area is full, all is well and the button sits where I want it to sit. However, in case the page content is very short, the grid is only as wide as to accommodate its content and then the button (which I am desperate to keep near the right edge of the screen) moves away from the right edge.

If I replace the grid and use a vertically oriented stack panel for the layout root, the button sits where I want it but then the content area is capable of growing beyond the bottom edge. So, when I place a listbox full of items into the main content area, it doesn't adjust its height to be completely in view, but the majority of items in that listbox are just rendered below the bottom edge of the display area.

I have tried using a third-party DockPanel layout manager and then docked the button in it's top section and set the button's HorizontalAlignment="Right" but the result was the same as with the grid, it also shrinks in size when there isn't enough content in the content area (or when title is short).

How do I do this then?

==EDIT==

I tried WPCoder's XAML, only I replaced the dummy text box with what I would have in a real page (stackpanel) and placed a listbox into the ContentPanel grid. I noticed that what I had before and what WPCoder is suggesting is very similar. Here's my current XAML and the page still doesn't grow to fit the width of the page and I get identical results to what I had before:

<phone:PhoneApplicationPage 
    x:Name="categoriesPage"
    x:Class="CatalogueBrowser.CategoriesPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
    xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="PortraitOrLandscape"  Orientation="Portrait" 
    mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768" 
    xmlns:ctrls="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
    shell:SystemTray.IsVisible="True">

    <Grid x:Name="LayoutRoot" Background="Transparent">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*" />
                <ColumnDefinition Width="Auto" />
            </Grid.ColumnDefinitions>
            <StackPanel Orientation="Horizontal" VerticalAlignment="Center" >
                <TextBlock Text="Browsing:" 
                       Margin="10,10" 
                       Style="{StaticResource PhoneTextTitle3Style}" />
                <TextBlock x:Name="ListTitle" 
                       Text="{Binding DisplayName}" 
                       Margin="0,10" 
                       Style="{StaticResource PhoneTextTitle3Style}" /&g开发者_StackOverflow社区t;
            </StackPanel>
            <Button Grid.Column="1"
                    x:Name="btnRefineSearch" 
                    Content="Refine Search" 
                    Style="{StaticResource buttonBarStyle}" 
                    FontSize="14" />
        </Grid>

        <Grid x:Name="ContentPanel" Grid.Row="1">
            <ListBox x:Name="CategoryList" 
                     ItemsSource="{Binding Categories}" 
                     Style="{StaticResource CatalogueList}" 
                     SelectionChanged="CategoryList_SelectionChanged"/>
        </Grid>
    </Grid>

</phone:PhoneApplicationPage>

This is what the page with the above XAML markup looks like in the emulator:

Does this achieve what you're after?

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto"/>
        <RowDefinition Height="*"/>
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*" />
        <ColumnDefinition Width="Auto"/>
    </Grid.ColumnDefinitions>

    <TextBox Grid.Column="0" Grid.Row="0" />
    <Button Content="Search" Grid.Column="1" Grid.Row="0" />
    <ScrollViewer Grid.Row="1" Grid.ColumnSpan="2"></ScrollViewer>
</Grid>

Tested in a Grid wiht the name ="ContentPanel" in a default page/project.

The code below should work for you. You'd just need to put the content in the grid named ContentPanel. If this doesn't work, you'll need to post your XAML that's not working.

<phone:PhoneApplicationPage 
    x:Class="WindowsPhoneApplication1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
    xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768"
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="Portrait" Orientation="Portrait"
    shell:SystemTray.IsVisible="True">

    <!--LayoutRoot is the root grid where all page content is placed-->
    <Grid x:Name="LayoutRoot" Background="Transparent">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*" />
                <ColumnDefinition Width="Auto" />
            </Grid.ColumnDefinitions>
            <TextBlock Text="CAPTION" VerticalAlignment="Center" />
            <Button Content="Button" Grid.Column="1" />
        </Grid>

        <!--ContentPanel - place additional content here-->
        <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
        </Grid>
    </Grid>

</phone:PhoneApplicationPage>

Thank you guys for your responses, they helped me locating the bug underneath the individual pages. In order to have nice page-flip transitions between pages, I used a style I copied from one of the WP7 samples. This style set the template for the PhoneApplicationFrame in a way that the VerticalAlignemnt and HorizontalAlignment, which is (I believe) by default set to Stretch, was overridden and so my pages were not laid out the way one would normally expect due to this special PhoneApplicationFrame template.

So the cause for all my headaches was lying down low underneath all the other layers of abstraction. I relied on its only providing me with the visually attractive page transitions, and not messing with any other aspect of the application, but then I took a much deeper look than I would prefer and noticed I need to set the Vertical/Horizontal Alignment to Stretch in several places which immediately sorted all problems out for me.

Cheers :-)