How to pass mouse EventArgs and other params?

Question

I'm using the Interaction dll and I want to "call" a method from the ViewModel and to pass her the mouse Args and another params.

I have tried to use the Microsoft.Expression.Interaction with the CallMethod like this:

<i:Interaction.Triggers>
    <i:EventTrigger EventName="MouseDown" >
        <!--This is used in order to pass eventArgs to func-->
        <ei:CallMethodAction MethodName="networkControl_MouseDown" TargetObject="{Binding}" />
    </i:EventTrigger>

But my problem is that the method networkControl_MouseDown need to use a parameter that is a view parameter, so I thought about passing this parameter as an argument to the function and I read that the CallMethodAction does not support argument passing.

Is there any solution to my problem?

Answer 1

You could use the MvvmLight toolkit. It has EventToCommand behavior wich has the property PassEventArgsToCommand.

Edit: Unfortunately you can only use one way or the other:

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525"
        xmlns:conv="clr-namespace:WpfApplication1"
        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
        xmlns:cmd ="http://www.galasoft.ch/mvvmlight">
    <Window.Resources>
        <conv:MultiValueConverter x:Key="MultiValueConverter" />
    </Window.Resources>
    <Grid>
        <Button>
            <i:Interaction.Triggers>
                <i:EventTrigger EventName="Click">
                    <cmd:EventToCommand PassEventArgsToCommand="True" Command="{Binding TestCommand}">
<!--You can only use EventArgs or CommandParameter. -->
                            <!--<cmd:EventToCommand.CommandParameter>
                                <MultiBinding Converter="{StaticResource MultiValueConverter}">
                                    <Binding Path="Parameter1" Mode="OneWay"/>
                                    <Binding Path="Parameter2" Mode="OneWay"/>
                                </MultiBinding>
                            </cmd:EventToCommand.CommandParameter>-->
                        </cmd:EventToCommand>
                    </i:EventTrigger> 
                </i:Interaction.Triggers>
            </Button>
        </Grid>
    </Window>

If you realy need to pass the EventArgs and additional parameters you would need to implement your own trigger. The source of Mvvm Light EventToCommand http://mvvmlight.codeplex.com/SourceControl/latest#GalaSoft.MvvmLight/GalaSoft.MvvmLight.Extras (NET35)/Command/EventToCommand.cs should get you started. Link not working: look for GalaSoft.MvvmLight -> Extas(NET35) -> Commands.

Edit: For using it with MultiBinding:

public ICommand TestCommand
{
 get
    {
        if(_testCommand == null)
        {
            _testCommand = new RelayCommand(OnTestCommand); //ICommand implementation
         }
         return _testCommand;
     }
}

public void OnTestCommand(object args)
{
    var array = (object[])args;
    var p1 = array[0];
    var p2 = array[1];
}

    public class MultiValueConverter : IMultiValueConverter
    {

        public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            //Important. Otherwise values in execute method of command will be null.
            return values.ToArray();
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }