xaml - GridView with 2 columns, fill width

Question

The result I want to achieve is pretty simple, a list with 2 columns, both with equal width. In Windows Phone 7/8 this could easily be achieved using a ListBox with a WrapPanel as ItemsPanel and setting the ItemWidth to 240 (as the screen width was 480).

Now I'm Writing a Universal App, but here the problem is that the screen is not guaranted to have a width of 480 (not even for the Phone it seems) so I can't set the ItemWidth as I want it to fill the width of the screen. I have been able to achieve almost the desired effect using the following XAML:

<GridView ItemsSource="{Binding Results}" Margin="12">
    <GridView.ItemTemplate>
        <DataTemplate>
            <Grid>
                <Image Source="{Binding SampleImage}" />
            </Grid>
        </DataTemplate>
    </GridView.ItemTemplate>

    <GridView.ItemsPanel>
        <ItemsPanelTemplate>
            <WrapGrid MaximumRowsOrColumns="2" Orientation="Horizontal" HorizontalChildrenAlignment="Stretch" VerticalChildrenAlignment="Stretch">
            </WrapGrid>
        </ItemsPanelTemplate>
    </GridView.ItemsPanel>
</GridView>

Which gives the following result:

As seen it successfully gives 2 columns with equal width, BUT the Grid in the GridView.ItemTemlate doesn't fill the whole width of each column. I have tried setting HorizontalAlignment="Stretch" on both that Grid and on the GridView itself witout any success. Anyone has any idea of this do this?

Answer 1

My solution is :

<GridView ItemsSource="{Binding Results}" Margin="12"
                       SizeChanged="GridView_SizeChanged"
                       x:Name="MyGridView">
<GridView.ItemTemplate>
    <DataTemplate>
        <Grid>
            <Image Source="{Binding SampleImage}" />
        </Grid>
    </DataTemplate>
</GridView.ItemTemplate>

<GridView.ItemContainerStyle>
            <Style TargetType="GridViewItem">
                <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
                <Setter Property="HorizontalAlignment" Value="Stretch"/>
                <Setter Property="VerticalContentAlignment" Value="Stretch"/>
                <Setter Property="VerticalAlignment" Value="Stretch"/>
            </Style>
</GridView.ItemContainerStyle>
</GridView>

Code Behind :

private void GridView_SizeChanged(object sender, SizeChangedEventArgs e)
    {
        var panel = (ItemsWrapGrid)MyGridView.ItemsPanelRoot;
        panel.ItemWidth =panel.ItemHeight= e.NewSize.Width / 2;
    }