mvvm-light toolkit not firing Window Loaded event
I have a Window and using MVVM light toolkit to bind to the Loaded event:
开发者_StackOverflow中文版<Window
...
xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WPF4"
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
...
>
<i:Interaction.Triggers>
<i:EventTrigger EventName="Loaded">
<cmd:EventToCommand Command="{Binding Loaded, Mode=OneWay}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</Window>
and in my view-model, I have the following:
private ICommand _loaded;
public ICommand Loaded
{
get
{
if (_loaded == null)
{
_loaded = CreateAsyncRelayCommand(p => OnLoaded());
}
return _loaded;
}
}
public void OnLoaded()
{
throw new NotImplementedException();
}
but on the window showing, the exception isn't thrown although the ICommand variable is being initialized when I put a break point in the Loaded property. I've tried changing to using the Initialized event, but still the same thing. This works fine in another Window I have in the same app, so I'm almost sure I'm doing everything correctly - could there be something I'm missing? When I bind with code-behind, it works fine, but I want to adhere to the mvvm pattern. Thanks in advance.
Try assigning the command inside your constructor, i.e.
public ViewModel() {
_loaded = CreateAsyncRelayCommand(p => OnLoaded());
}
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