I have a need of one DependencyProperty from a View in my ViewModel constructor:
My problem: MEF wouldn't SatisfyImports() 'because it is marked with one or more ExportAttributes' (that is the exception)
This is the code structure for the VIEW:
public class MyView : UserControl
{
[Export(MethodTypes.ChartType)]
public Charts MyChartType
{
get
{
object k = GetValue(ChartTypeProperty);
Charts f = (Charts)Enum.Parse(typeof(Charts), k.ToString(), true);
return f;
}
set
{
SetValue(ChartTypeProperty, value);
}
}
[Import(ViewModelTypes.GenericChartViewModel)]
public object ViewModel
{
set
{
DataContext = value;
}
}
public MyView()
{
InitializeComponent();
if (!ViewModelBase.IsInDesignModeStatic)
{
// Use MEF To l开发者_如何学编程oad the View Model
CompositionInitializer.SatisfyImports(this);
}
}
}
and the VIEWMODEL:
[PartCreationPolicy(CreationPolicy.NonShared)]
[Export(ViewModelTypes.GenericChartViewModel)]
public class GenericChartViewModel
{
[ImportingConstructor]
public GenericChartViewModel([Import(MethodTypes.ChartType)] Charts forChartType)
{
string test = forChartType.ToString();
}
}
Please give me any hints on this or maybe suggest a better solution for passing parameters through mef
In my case, I would need to pass only dependecyproperty's for now...
Thanks
Your work around isn't really good.. can't you remove the export from ChartTypes and pass it manually to whoever wants it? I presume the viewmodel is only one insterested in it..
I managed to put this through !
Instead of the code in the default constructor, I use:
void MyView_Loaded(object sender, RoutedEventArgs e)
{
if (!ViewModelBase.IsInDesignModeStatic)
{
var catalog = new TypeCatalog(typeof(GenericChartViewModel));
var container = new CompositionContainer(catalog);
container.ComposeParts(this);
}
}
and the dependencyproperty value is correctly propagated to the ViewModel (must do this after control is loaded, or the property will have its default value)
However, I would be very grateful if someone could:
- tell me how generate a catalog from another non-referenced assembly?
Thanks
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