如何让listbox内的项 某一个元素靠右

[starskun888]

 <ListBox sltoolkit:TiltEffect.IsTiltEnabled="True" x:Name="callhistory" MouseLeftButtonDown="mousedown"  Grid.RowSpan="2" SelectionChanged="selectchange">
                       
                        <StackPanel  Orientation="Horizontal" >
                            <Button BorderThickness="0">
                                <Image Source="/icons/laidian.png"></Image>
                            </Button>
                            <StackPanel VerticalAlignment="Center">
                                <TextBlock Name="displayname" Text="安可" FontSize="30" Foreground="#17e10d"></TextBlock>
                                <TextBlock Name="phonenum" Text="111111111"></TextBlock>
                                
                            </StackPanel>
                            <TextBlock Name="Time"  Text="17:00" VerticalAlignment="Center"></TextBlock>
                           
                        </StackPanel>
</Listbox>

//如何让"Time"控件排在最右边。。。