Develop Reference

In WPF is the contents of ListBox the same as its bound ItemsSource? and how do I seperate them?

I have a ListBox with its ItemsSource bound to some UserControl-s and shown based on their current states(IsVisible)
Here is the code
<ListBox x:Name="sidebarList" Margin="0,0,10,10" ItemsSource="{Binding Modules, Mode=TwoWay}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Margin="0 5 0 5" Visibility="{Binding IsVisible, Mode=TwoWay}">
<TextBlock Text="{Binding Title}" FontWeight="Bold" />
<TextBlock Margin="0 5 0 0" MaxWidth="200" Foreground="Gray" Text="{Binding Detail}"
TextWrapping="WrapWithOverflow">
</TextBlock>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
<ListBox.ItemContainerStyle>
<Style TargetType="{x:Type ListBoxItem}">
<Style.Triggers>
<DataTrigger Binding="{Binding IsVisible}" Value="Collapsed">
<Setter Property="Visibility" Value="Collapsed"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ListBox.ItemContainerStyle>
</ListBox>
And now I'm trying to only get "IsVisible"/selected parts when a button is pressed. As of right now, the ListBox actually contains every option but just showing the IsVisible ones(at least that's what I think).
How do I only get the selected options? I have tried to use a new List with the same type as the UserControl-s type(which I placed in app.xaml.cs to call from anywhere) and add to that list when their state changes to IsVisible
but the List doesn't show up in my classes where I check them.

Sounds like what you really need is a view-model. Bind your Listbox to a view model that has an observable collection that only shows view-models of the items you want to present.
I can give you a more "correct" answer about how to do it with style/data-triggers but you should really just learn about MVVM and use a view-model to simplify.

Dynamically use different UserControl based on datacontext

I have a chunk of xaml that duplicates the same pattern six times and would like to reduce that footprint by eliminating the duplication. I'm running into one snag that I need help with.
Background: I have a class that instantiates another class six times (phases of a project as you will).
public ECN(string ecnNumber) {
_ECNNumber = ecnNumber;
//instantiate each phase to be populated or not
_PurchaseParts = new ECNPhase();
_PieceParts = new ECNPhase();
_Weldments = new ECNPhase();
_BOMCfg = new ECNPhase();
_Cleanup = new ECNPhase();
_PRAF = new ECNPhase();
}
Inside each phase is a collection of Changes (another class) referenced in the ECNPhase Class. Each phase has data that is unique to each phase that is shown in a unique view, this is where my snag is which I will show later.
Example of the duplicate xaml Code with the main difference being the different view inside each expander:
<StackPanel Margin="0">
<!--Section for Purchase parts-->
<StackPanel Orientation="Horizontal" >
<CheckBox Margin="0,5,5,5" IsChecked="{Binding Path=MyWorkspace.CurrentSelectedItem.PurchaseParts.HasPhase,Mode=TwoWay}"/>
<StackPanel Orientation="Horizontal">
<StackPanel.Style>
<Style TargetType="{x:Type StackPanel}">
<Setter Property="IsEnabled" Value="False"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=MyWorkspace.CurrentSelectedItem.PurchaseParts.HasPhase}" Value="True">
<Setter Property="IsEnabled" Value="True"/>
</DataTrigger>
</Style.Triggers>
</Style>
</StackPanel.Style>
<Expander Header="Purchase Parts" Margin="0,0,10,0" Width="110">
<view:PurchasePartsView/>
</Expander>
<CheckBox Content="Submit" Margin="10,5,0,5"/> <!--add a command to handle the submit checkbox event-->
<Label Content="Status:" Margin="10,0,0,0" HorizontalContentAlignment="Right" Width="60"/>
<Label Content="{Binding Path=MyWorkspace.CurrentSelectedItem.PurchaseParts.Status}"/>
</StackPanel>
</StackPanel>
<!--Section for Piece Parts-->
<StackPanel Orientation="Horizontal">
<CheckBox Margin="0,5,5,5" IsChecked="{Binding Path=MyWorkspace.CurrentSelectedItem.PieceParts.HasPhase,Mode=TwoWay}"/>
<StackPanel Orientation="Horizontal">
<StackPanel.Style>
<Style TargetType="{x:Type StackPanel}">
<Setter Property="IsEnabled" Value="False"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=MyWorkspace.CurrentSelectedItem.PieceParts.HasPhase}" Value="True">
<Setter Property="IsEnabled" Value="True"/>
</DataTrigger>
</Style.Triggers>
</Style>
</StackPanel.Style>
<Expander Header="Piece Parts" Margin="0,0,10,0" Width="110">
<view:PiecePartsView/>
</Expander>
<CheckBox Content="Submit" Margin="10,5,0,5"/> <!--add a command to handle the submit checkbox event-->
<Label Content="Status:" Margin="10,0,0,0" HorizontalContentAlignment="Right" Width="60"/>
<Label Content="{Binding Path=MyWorkspace.CurrentSelectedItem.PieceParts.Status}"/>
</StackPanel>
</StackPanel>
<!--duplicated four more times-->
</StackPanel>
What I'd like to do is:
<StackPanel>
<view:PhaseView DataContext="{Binding Path=MyWorkspace.CurrentSelectedItem.PurchaseParts}"/>
<view:PhaseView DataContext="{Binding Path=MyWorkspace.CurrentSelectedItem.PieceParts}"/>
<!--four more phases-->
</StackPanel>
Where the PhaseView will be the template that handles the duplication and this is where I'm hitting a snag. Each phase needs a unique view (userControl) selected based off of the datacontext of the PhaseView.
<StackPanel Orientation="Horizontal" >
<CheckBox Margin="0,5,5,5" IsChecked="{Binding Path=HasPhase,Mode=TwoWay}"/>
<StackPanel Orientation="Horizontal">
<StackPanel.Style>
<Style TargetType="{x:Type StackPanel}">
<Setter Property="IsEnabled" Value="False"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=HasPhase}" Value="True">
<Setter Property="IsEnabled" Value="True"/>
</DataTrigger>
</Style.Triggers>
</Style>
</StackPanel.Style>
<Expander Header="DisplayName" Margin="0,0,10,0" Width="110">
<!--add somthing here to select the correct view based on the datacontext-->
<!--<local:PurchasePartsView/> This user control adds a datagrid that is unique to each phase-->
</Expander>
<CheckBox Content="Submit" Margin="10,5,0,5"/> <!--add a command to handle the submit checkbox event-->
<Label Content="Status:" Margin="10,0,0,0" HorizontalContentAlignment="Right" Width="60"/>
<Label Content="{Binding Path=Status}"/>
</StackPanel>
</StackPanel>
I was thinking of using a datatrigger somehow lik shown below, but I haven't had any luck figuring it out. I know there's got to be a way to do this, and it's probably something simple and dumb. Any help would be much appreciated.
<DataTrigger Binding="{Binding Path=DisplayName}" Value="Purchase Parts">
<Setter Property="DataContext" Value="{Binding }"/> <!--Don't know how to bind the DataContext-->
</DataTrigger>
Thanks,

Ok, thanks to Bradley I looked into the DataTemplateSelector and this is what I came up with.
In my UserControl resources I set up several DataTemplates and a reference to the TemplateSelector class that overides the DataTemplateSelector class.
XAML Resources:
<UserControl.Resources>
<local:TemplateSelector x:Key="myTemplateSelector"/>
<DataTemplate x:Key="PurchasePartsTemplate">
<view:PurchasePartsView/>
</DataTemplate>
<DataTemplate x:Key="PiecePartsTemplate">
<view:PiecePartsView/>
</DataTemplate>
<!--Four more templates-->
</UserControl.Resources>
Code Behind for DataTemplateSelector override. Note: I couldn't figure out a way to bind to the ECNPhase class so I bound to the DisplayName property in my class to pull out the correct instance being represented.
class TemplateSelector : DataTemplateSelector {
public override DataTemplate SelectTemplate(object item, DependencyObject container) {
FrameworkElement element = container as FrameworkElement;
if(element != null && item != null && item is string) {
string phase = (string)item;
if(phase == "Purchase Parts") {
return element.FindResource("PurchasePartsTemplate") as DataTemplate;
}else if(phase == "Piece Parts") {
return element.FindResource("PiecePartsTemplate") as DataTemplate;
}
}
return null;
}
}
I'm calling this class in my UserContol like this:
<Expander Header="{Binding Path=DisplayName}" Margin="0,0,10,0" Content="{Binding Path=DisplayName}"
ContentTemplateSelector="{StaticResource myTemplateSelector}"/>
There isn't an items control associated with the expander so I used the content control. I pass the DisplayName into the control property and the contentTemplateSelector uses the myTemplateSelector resource which goes into the codebehind and selects the appropriate datatemplate to use based on the DisplayName.
Now I can call my reusable template like so:
<StackPanel Margin="0">
<view:ChangePhaseView DataContext="{Binding Path=MyWorkspace.CurrentSelectedItem.PurchaseParts}"/>
<view:ChangePhaseView DataContext="{Binding Path=MyWorkspace.CurrentSelectedItem.PieceParts}"/>
</StackPanel>
#Bradley, thank you for pointing me in the right direction.

Conditional Context Menu Triggers

I currently have two buttons. One button is to Showappointments(), the other is ShowTask(). When either is clicked the FontWeight of that button goes to bold. Only one can be bolded at a time. I use that as the indicator to show which is being displayed.
The values are then displaye in a ListBox. I'm trying to have a condition such that when ShowTask fontweight is Bold it'll display the corresponding contextMneu for the Task, and it'll display a different set of contextmenus for Appointments.
<ListBox ItemsSource="{Binding FilteredEventsCollection}"
<Style TargetType="{x:Type ListBox}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=AppointmentBold}" Value="Bold">
<Setter Property="ContextMenu" Value="{StaticResource Menu1}"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel cal:Message.Attach="[Event MouseDoubleClick] = [Action Open()]">
<TextBlock Text="{Binding Date, StringFormat=g}" Foreground="Black" FontWeight="Bold" FontFamily="Segoe UI"/>
<TextBlock Text="{Binding Title}" />
<TextBlock Text="{Binding Company}" Foreground="Black"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
User Control Resources
<ContextMenu x:Key="TaskMenu">
<MenuItem>Open This Task</MenuItem>
</ContextMenu>
<ContextMenu x:Key="AppointmentMenu">
<MenuItem>Open This Appointment</MenuItem>
</ContextMenu>
This piece of code crashes right away, I'm wondering if I'm approaching correct and if I can get some guidance

how to trigger visibility change to child controls with a trigger

I have a databound listbox thet generates items in a datatemplate of type wrappanel with other controls within it. I would like to have the behavior to, when I change the visibility to affect differently the controls within the wrappanel
<WrapPanel Orientation="Horizontal" Tag="{Binding .}" HorizontalAlignment="Stretch" Visibility="{Binding editMode, Converter={StaticResource VisibilityConverter}}">
<Label Width="150" Content="{Binding Path=avaiableAttribute.Text}" Name="lblName"/>
<Label Width="150"
Content="{Binding Path=informationItem.ItemString, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
Initialized="Label_Initialized"
Name="lblText" />
<ContentPresenter MinWidth="200" MaxHeight="200" Content="{Binding ., Converter={StaticResource InformationItemConverter}, Mode=TwoWay}" HorizontalAlignment="Stretch"
Name="cpValue"
Initialized="ContentPresenter_Initialized"/>
<WrapPanel.Style>
<Style TargetType="{x:Type WrapPanel}">
<Style.Triggers>
<Trigger Property="Visibility" Value="Visible" >
<Trigger.Setters>
<Setter TargetName="lblText" Property="Visibility" Value="Collapsed" />
<Setter TargetName="cpValue" Property="Visibility" Value="Visible" />
</Trigger.Setters>
</Trigger>
</Style.Triggers>
</Style>
</WrapPanel.Style>
</WrapPanel>
I just get the following build error
the property 'targetname' does not represent a valid target for the 'setter' because an element

When using a Setter, the TargetName only applies to elements in a Template. This means your Trigger has to exist in a DataTemplate or ControlTemplate. The easiest way to do what you want to do is to create your own IValueConverter for the inverse of BooleanToVisibilityConverter (ie return Visibility.Collapsed when value is true).

How do you bind a viewmodel which implements IDataErrorInfo to a UserControl and propagate the validation errors?

I've written a UserControl that exposes a few dependency properties to modify the layout of the control (i.e. think of it as a generic type-safe editor control - so my data types are dates (edited through a date picker), enumerations (edited through a combobox) and a numeric (edited through a textbox). I've also exposed the value of the 3 editor controls as a dependency property so that it can be databound.
The controls within the usercontrol all bind to the exposed dependency properties to get their values (with appropriate converters where necessary).
This control forms a tiny piece of a larger UI which binds to a viewmodel - the value to be edited, the datatype flag for the custom control and a list of possible valid values are all bound to an object in the viewmodel.
My problem is this: I've implemented IDataErrorInfo on the viewmodel and set the controls' bindings within the custom usercontrol to have ValidatesOnDataErrors=True, NotifyOnValidationError=True but the validation is not displaying.
This is the XAML for my usercontrol (there is no other code-behind logic beyond the dependency property declarations):
<UserControl.Resources>
<!-- Converters -->
<local:ValidationBooleanToImageConverter x:Key="ValidationBooleanToImageConverter"/>
<local:ValidationErrorToStringConverter x:Key="ValidationErrorToStringConverter"/>
<local:DataTypeToVisibilityConverter DataType="Date" x:Key="DateDataTypeToVisibilityConverter"/>
<local:DataTypeToVisibilityConverter DataType="Numeric" x:Key="NumericDataTypeToVisibilityConverter"/>
<local:DataTypeToVisibilityConverter DataType="Enumeration" x:Key="EnumerationDataTypeToVisibilityConverter"/>
<local:DateToStringConverter x:Key="DateToStringConverter"/>
<!-- Styles -->
<Style TargetType="{x:Type TextBox}">
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter Property="ToolTip"
Value="{Binding RelativeSource={RelativeSource Self}, Path=(Validation.Errors).CurrentItem, Converter={StaticResource ResourceKey=ValidationErrorToStringConverter}}"/>
</Trigger>
</Style.Triggers>
</Style>
</UserControl.Resources>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition Width="16"/>
</Grid.ColumnDefinitions>
<toolkit:DatePicker Height="25" Margin="0,0,5,0" Visibility="{Binding Path=DataType, ElementName=UserControl, Converter={StaticResource ResourceKey=DateDataTypeToVisibilityConverter}}" SelectedDate="{Binding Path=Value, ElementName=UserControl, Converter={StaticResource ResourceKey=DateToStringConverter}}"/>
<ComboBox Height="25" Margin="0,0,5,0" Visibility="{Binding Path=DataType, ElementName=UserControl, Converter={StaticResource ResourceKey=EnumerationDataTypeToVisibilityConverter}}" SelectedItem="{Binding Path=Value, ElementName=UserControl, Mode=TwoWay}" ItemsSource="{Binding Path=Items, ElementName=UserControl}" />
<TextBox x:Name="_txtValue" Height="25" Margin="0,0,5,0" Visibility="{Binding Path=DataType, ElementName=UserControl, Converter={StaticResource ResourceKey=NumericDataTypeToVisibilityConverter}}" Text="{Binding Path=Value, ElementName=UserControl, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True, NotifyOnValidationError=True}"/>
<Image Grid.Column="2" Grid.Row="0" Source="{Binding ElementName=_txtValue, Path=(Validation.HasError), Converter={StaticResource ResourceKey=ValidationBooleanToImageConverter} }" ToolTip="{Binding ElementName=_txtValue, Path=ToolTip}" Width="16" Height="16"/>
</Grid>
...and the usercontrol reference from within the larger View is...
<control:ValueEditorControl DataType="{Binding Path=ContextualSelectedTagDataType}" Items="{Binding Path=ContextualSelectedTagItems}" Value="{Binding Path=ContextualSelectedTagDataObjectValue, Mode=TwoWay}" Height="25" VerticalAlignment="Top"/>
Can anyone point me in the right direction?

Does your VM implement INotifyPropertyChanged? Even if you implement IDataErrorInfo if WPF isn't notified of changes to the VM then it won't bind to those changes.
That being said I would change your ToolTip setter to this:
<Setter Property="ToolTip"
Value="{Binding RelativeSource={RelativeSource Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
If you want the entire Style I would recommend this:
<Style TargetType="{x:Type TextBox}">
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
<AdornedElementPlaceholder Name="controlWithError" />
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="true">
<Setter Property="Background" Value="LightPink"/>
<Setter Property="ToolTip"
Value="{Binding RelativeSource={RelativeSource Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</Style.Triggers>
</Style>