Silverlight 4.0: GridSplitter is splitting incorrectly

Question

Please help, the grid splitter in not splitting correctly to the right, the testing button content. Is there anything I've missed out in using grid splitter?

<local:LayoutTemplateSelector Content="{Binding}">
                    <local:LayoutTemplateSelector.VerticalLeftRight>
                        <DataTemplate>
                            <Grid ShowGridLines="True" Background="Orange"  Height="{Binding Height}" 
                                  HorizontalAlignment="Stretch" VerticalAlignment="Stretch" >
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width=".25*"/>
                                    <ColumnDefinition Width="10" />
                                    <ColumnDefinition Width=".70*"/>

                                </Grid.ColumnDefinitions>
                                <Button  Grid.Column="0" Content="Test"  Width="{Binding ChartWidth}" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch"/>
                                <sdk:GridSplitter Grid.Column="1" ShowsPreview="True" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"/>
                                <Button Content="Testing"  Width="{Binding SectionWidth}"  Grid.Column="2"
                                    HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
                                    HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch"/>
                            </Grid>
                        </DataTemplate>
                    </local:LayoutTemplateSelector.VerticalLeftRight>
                </local:LayoutTemplateSelector>

Answer 1

You need to use fixed width for the first column and star for the remaining one.

<Grid.ColumnDefinitions>
             <ColumnDefinition Width="200" MinWidth="50" MaxWidth="250"/>
             <ColumnDefinition Width="10" />
             <ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>

It is usually a good idea (but not essential) to set min and max values for the first column to keep it looking sensible.