I have a TabControl and each Tab can contain the same UI but with different data. In any tab the user can click on a button and bring up a popup. This sets a Style property to the ViewModel telling it what style to use for the popup UI. The Style gets bound to a custom DependecyProperty that is attached to a custom PopupUserControl. My problem is that when the a 2nd copy of the popup gets opened in another tab, I get the following error (regardless of what Style is applied):
Specified element is already the logical child of another element. Disconnect it first.
ButtonClick command:
MyViewModel vm = ((Button)sender).DataContext as MyViewModel;
if (vm != null)
{
Style popupStyle = (Style)Application.Current.FindResource("SomePopupStyle");
vm.EditPanelStyle= popupStyle ;
}
This triggers a PropertyChange event on the Style
public Style EditPanelStyle
{
get { return _editPanelStyle; }
set
{
if (_editPanelStyle != value)
{
_editPanelStyle = value;
OnPropertyChanged("EditPanelStyle");
}
}
}
Which triggers the OnPropertyChanged event in the ViewModelBase
protected virtual void OnPropertyChanged(string propertyName)
{
this.VerifyPropertyName(propertyName);
PropertyChangedEventHandler handler = this.PropertyChanged;
if (handler != null)
{
var e = new PropertyChangedEventArgs(propertyName);
handler(this, e);
}
}
The error occurs at line handler(this, e); in the ViewModelBase
EDIT
The TabItem contains a Canvas and a bunch of panels that can be added/removed/moved/etc. Each Panel has its own resource directory. From within the Panel I can set the PopupStyle just fine and it gets applied without a problem. The Style used within the panels is also defined in the PanelResourceDictionary.
The main difference with the one that is failing and the ones succeeding is the Style is located in different locations.
EDIT #2 Style that is failing - LookupDialog is a custom WPF UserControl
<!-- Popup Style for LookupDialog -->
<Style x:Key="LookupDialogBaseStyle" TargetType="{x:Type localControls:DraggablePanel}" BasedOn="{StaticResource GenericPopupStyle}">
<Setter Property="Canvas.Left" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualWidth, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.25}" />
<Setter Property="Canvas.Top" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualHeight, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.3}" />
<Setter Property="Width" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualWidth, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.5}" />
<Setter Property="Height" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualHeight, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.4}" />
<!--<Setter Property="localControls:PopupPanel.PopupEnterKeyCommand" Value="{Binding Path=SaveCommand}" />-->
<Setter Property="localControls:PopupPanel.PopupEscapeKeyCommand" Value="{Binding Path=CancelCommand}" />
<Setter Property="Header" Value="{Binding Path=Header}" />
<Setter Property="localControls:PopupPanel.BackgroundOpacity" Value="0" />
<Setter Property="Content">
<Setter.Value>
<localControls:LookupDialog
DataContext="{Binding}"
BorderBrush="{StaticResource DarkColor}" />
</Setter.Value>
</Setter>
</Style>
<!-- Base Style for a Popup (DraggablePanel) -->
<Style x:Key="GenericPopupStyle" TargetType="{x:Type localControls:DraggablePanel}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type localControls:DraggablePanel}">
<Border Height="{TemplateBinding Height}" Width="{TemplateBinding Width}">
<DockPanel>
<!-- Header -->
<Border
DockPanel.Dock="Top"
MinHeight="20"
Background="{DynamicResource TabItem_BackgroundBrush_Unselected}"
BorderBrush="{StaticResource DarkColor}"
BorderThickness="1"
CornerRadius="5,5,0,0"
Padding="2,3,2,2"
SnapsToDevicePixels="True"
>
<ContentPresenter x:Name="PART_DraggablePanelHeader" ContentSource="Header" />
</Border>
<!-- Content -->
<Border Background="{StaticResource DefaultBackground}"
BorderBrush="{StaticResource DarkColor}"
BorderThickness="1,0,1,1"
SnapsToDevicePixels="True">
<ContentPresenter ContentSource="Content" />
</Border>
</DockPanel>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Style that Works:
<!-- Example Popup Style for a Panel -->
<Style x:Key="AgentDesktop_NotesPanelPopupStyle" TargetType="{x:Type ContentControl}">
<Setter Property="Canvas.Left" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualWidth, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.2}" />
<Setter Property="Canvas.Top" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualHeight, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.32}" />
<Setter Property="Width" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualWidth, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.6}" />
<Setter Property="Height" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type localControls:PopupPanel}},
Path=ActualHeight, Converter={StaticResource PercentToDoubleConverter}, ConverterParameter=.36}" />
<Setter Property="localControls:PopupPanel.PopupEnterKeyCommand" Value="{Binding Path=SaveCommand}" />
<Setter Property="localControls:PopupPanel.PopupEscapeKeyCommand" Value="{Binding Path=HidePopupCommand}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<!-- Control Template removed to make this easier to read, but it's created from standard WPF controls with nothing special -->
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>