Question

This is a problem I’ve been trying to solve for a couple of days but I’m yet to find a good solution.

I have a main WPF window which contains a StackPanel. I also have a class called “MessageManagement” which contains a List of custom WPF controls called “MessagePreview”.

MessagePreview

<UserControl x:Class="FinalYearProject.MessagePreview"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         mc:Ignorable="d" 
         d:DesignHeight="58" d:DesignWidth="254" Background="White" BorderThickness="1" BorderBrush="#FF320000">
<Grid Name="grid1">
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="50" MaxWidth="50" MinWidth="50" />
        <ColumnDefinition Width="197*" MinWidth="20" />
    </Grid.ColumnDefinitions>
    <Grid Grid.Column="1" Name="grid2">
        <Grid.RowDefinitions>
            <RowDefinition Height="31*" />
            <RowDefinition Height="34*" />
            <RowDefinition Height="33*" />
        </Grid.RowDefinitions>
        <Label Content="-ERROR-" Height="28" HorizontalAlignment="Left" Margin="2,1,0,0" Name="senderLabel" VerticalAlignment="Top" Foreground="#FF0000B4" Grid.RowSpan="2" />
        <Label Content="-ERROR-" Height="33" HorizontalAlignment="Left" Name="previewLabel" VerticalAlignment="Top" Margin="-1,17,0,0" Grid.RowSpan="3" />
        <Label Content="-Error-" Grid.Row="1" Height="28" HorizontalAlignment="Left" Margin="0,16,6,0" Name="timeLabel" VerticalAlignment="Top" Grid.RowSpan="2" Width="196" />
    </Grid>
    <Grid Name="grid3">
        <Grid.RowDefinitions>
            <RowDefinition Height="29*" />
            <RowDefinition Height="27*" />
        </Grid.RowDefinitions>
        <Image Height="38" HorizontalAlignment="Center" Margin="3,0,6,20" Name="image1" Stretch="Fill" VerticalAlignment="Bottom" Width="41" Source="/FinalYearProject;component/Images/twitter-bird-light-bgs.png" Grid.RowSpan="2" />
        <CheckBox Height="16" Margin="15,0,22,6" Name="checkBox" VerticalAlignment="Bottom" Grid.Row="1" IsChecked="False" />
    </Grid>
</Grid>

MessageManagement

List<MessagePreview> unread = new List<MessagePreview>();

    public bool messagesLocked()
    {
        foreach (MessagePreview m in unread)
        {
            if ((bool)m.checkBox.IsChecked)
                return true;
        }
        return false;
    }

MainWindow C#

MessageManagement messageManagement;

MessagesPanel1 is a blank StackPanel inside MainWindow

if (!messageManagement.messagesLocked())
{
       foreach (Message m in messageManagement.getListOfMessages()
       {
              MessagesPanel1.Children.Add(m)
       }
}

When you add the custom control to the StackPanel it creates a duplicate of the original, which means changing a value on the controls in the StackPanel does not affect the controls in my MessageManagement List.

Is there a way that I can reference my original controls so that they change together? I looked into DataBinding but I’m not sure if that’s the right area.

Answer 1

Again, You do not make a List of UI elements in WPF. You use an ItemsControl and set its ItemTemplate Property to whatever UI you need to represent your items:

 <ItemsControl ItemsSource="{Binding Messages}">
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <!-- Everything you placed in your usercontrol, or else an instance of your usercontrol itself -->
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>