MainWindow.xaml

<Window
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:Model="clr-namespace:LocalIM.Model" x:Class="LocalIM.MainWindow"
        MinHeight="200" MinWidth="300"
        Title="Local IM" Height="300" Width="300" WindowStartupLocation="CenterScreen" ResizeMode="CanResizeWithGrip">
    <Window.Resources>
        
    </Window.Resources>
    <Grid>
        <Grid.Effect>
            <DropShadowEffect ShadowDepth="2"/>
        </Grid.Effect>
        <Grid.Background>
            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                <GradientStop Color="White" Offset="1"/>
                <GradientStop Color="#FF8C8C8C"/>
                <GradientStop Color="#FFE9E9E9"/>
            </LinearGradientBrush>
        </Grid.Background>
        <DockPanel>
            <StatusBar DockPanel.Dock="Bottom">
                <TextBlock Text="{Binding StatusText}" Margin="5,5,5,5"/>
            </StatusBar>
            <StackPanel Orientation="Vertical" DockPanel.Dock="Right" Margin="5,5,5,5">
                <Button Content="Settings"/>
            </StackPanel>            
            <DockPanel DockPanel.Dock="Left">
                <TextBlock Text="Online Contacts" Margin="5,5,5,5" DockPanel.Dock="Top"/>
                <ListBox ItemsSource="{Binding ContactViewModels}" DockPanel.Dock="Bottom" Background="Transparent">
                    <ListBox.ItemContainerStyle>
                        <Style TargetType="ListBoxItem">
                            <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
                        </Style>
                    </ListBox.ItemContainerStyle>
                    <ListBox.ItemTemplate>
                        <DataTemplate>
                            <DockPanel Height="30" Background="Transparent">
                                <DockPanel.InputBindings>
                                    <MouseBinding Command="{Binding ShowContactChatCommand}" MouseAction="LeftDoubleClick"/>
                                </DockPanel.InputBindings>
                                <TextBlock Text="{Binding UnreadMessagesCount}" ToolTip="Unread Messages" FontWeight="Bold" Margin="10,0" VerticalAlignment="Center" DockPanel.Dock="Right">
                                    <TextBlock.Style>
                                        <Style TargetType="{x:Type TextBlock}">
                                            <Style.Triggers>
                                                <DataTrigger Binding="{Binding UnreadMessagesCount}" Value="0">
                                                    <Setter Property="Visibility" Value="Hidden"/>
                                                </DataTrigger>
                                            </Style.Triggers>
                                        </Style>
                                    </TextBlock.Style>
                                </TextBlock>
                                <TextBlock Text="{Binding Contact.Username}" ToolTip="{Binding LastActionText}" VerticalAlignment="Center" DockPanel.Dock="Left">
                                <TextBlock.Style>
                                        <Style TargetType="{x:Type TextBlock}" BasedOn="{StaticResource BasicTextBlock}">
                                            <Style.Triggers>
                                                <DataTrigger Binding="{Binding IsIdle}" Value="false">
                                                    <Setter Property="Foreground" Value="Green"/>
                                                </DataTrigger>
                                                <DataTrigger Binding="{Binding IsIdle}" Value="true">
                                                    <Setter Property="Foreground" Value="Yellow"/>
                                                </DataTrigger>
                                                <DataTrigger Binding="{Binding IsInActive}" Value="True">
                                                    <Setter Property="Foreground" Value="Red"/>
                                                </DataTrigger>
                                            </Style.Triggers>
                                        </Style>
                                    </TextBlock.Style>
                                </TextBlock>
                            </DockPanel>
                        </DataTemplate>
                    </ListBox.ItemTemplate>
                </ListBox>
            </DockPanel>
        </DockPanel>

    </Grid>
</Window>