HelIo,
I have a problem of random broken binding with the application in MVVM I'm working on. Here is the error message I have :
quote System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.UserControl', AncestorLevel='1''. BindingExpression:Path=DataContext.vContextMenuMasters; DataItem=null; target element is 'ContextMenu' (Name=''); target property is 'Visibility' (type 'Visibility')
quote System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.UserControl', AncestorLevel='1''. BindingExpression:Path=DataContext.dcFilteringControl.AddMasterCommand; DataItem=null; target element is 'MenuItem' (Name=''); target property is 'Command' (type 'ICommand') System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.UserControl', AncestorLevel='1''. BindingExpression:(no path); DataItem=null; target element is 'MenuItem' (Name=''); target property is 'CommandParameter' (type 'Object') System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.Control', AncestorLevel='1''. BindingExpression:Path=Foreground; DataItem=null; target element is 'Path' (Name=''); target property is 'Fill' (type 'Brush') System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='ZSYS.WCTL.WebWindow', AncestorLevel='1''. BindingExpression:Path=DataContext.brushTitleBarBackground; DataItem=null; target element is 'MenuItem' (Name=''); target property is 'Background' (type 'Brush')...
My code is :
<UserControl x:Class="UserControls.MastersUserControl"
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"
xmlns:local="clr-namespace:UserControls"
xmlns:VM="clr-namespace:ViewModels"
xmlns:Converter="clr-namespace:Classes"
x:Name="ctlMasterUserControl"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
mc:Ignorable="d"
d:DesignHeight="984" d:DesignWidth="1280">
<UserControl.Resources>
<ContextMenu x:Key="ContextMenuMaster"
Visibility="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}, Path=DataContext.vContextMenuMasters}">
<MenuItem Header="New"
Style="{StaticResource MenuItemStyle}"
Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}, Path=DataContext.dcFilteringControl.AddMasterCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=UserControl}}"
>
<MenuItem.Icon>
<Path Width="15"
Height="{Binding Path=ActualWidth, RelativeSource={RelativeSource Self}}"
Style="{StaticResource Plus}"/>
</MenuItem.Icon>
</MenuItem>
<MenuItem Header="New Master For Export"
Style="{StaticResource MenuItemStyle}"
Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}, Path=DataContext.dcFilteringControl.AddMasterTemplateCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=UserControl}}"
>
<MenuItem.Icon>
<Path Width="15"
Height="{Binding Path=ActualWidth, RelativeSource={RelativeSource Self}}"
Style="{StaticResource PlusTemplate}"/>
</MenuItem.Icon>
</MenuItem>
...
</ContextMenu>
<UserControl.Resources>
<Grid Grid.Row="1" Background="{StaticResource MainWindowGreyBackground}" ContextMenu="{DynamicResource ContextMenuMaster}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
...
</Grid>
For example each time I run this code the binding becomes broken but no other exception is raised :
private void RefreshData(object obj)
{
try
{
Task.Run(async () => await GetMasters()).ContinueWith(a =>
{ //Display the ContextMenu if needed
DisplayContextMenuIfNeeded();
});
}
catch (Exception ex)
{
System.Windows.MessageBox.Show(ex.ToString(), System.Reflection.Assembly.GetExecutingAssembly().GetName().Name + " : Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Exclamation);
}
}
private void DisplayContextMenuIfNeeded()
{
//Display the context Menu if the option was activated in the settings
if (MainWindowViewModel.objUIParameters != null)
{
if (MainWindowViewModel.objUIParameters.bIsCheckedShowContextMenu) vContextMenuMasters = Visibility.Visible;
else vContextMenuMasters = Visibility.Collapsed;
}
if ((bool)Application.Current.Properties["Valid"])
{
vCloneMasterMenyEntry = Visibility.Visible;
}
else
{
vCloneMasterMenyEntry = Visibility.Collapsed;
}
}
Thanks per advance for your help
EDIT : If I write
<Grid Grid.Row="1" ContextMenu="{DynamicResource ContextMenuMaster}" Tag="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=WCTL602:WebWindow}}">
...
<ListView.ItemContainerStyle>
<Setter Property="ContextMenu" Value="{DynamicResource ContextMenuMaster}" />
<Setter Property="Tag" Value="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=WCTL602:WebWindow}}"/>
...
I obtain a broken binding :
quote System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='WebWindow', AncestorLevel='1''. BindingExpression:Path=; DataItem=null; target element is 'ListViewItem' (Name=''); target property is 'Tag' (type 'Object')
Please help ;)
