MVVM - Bind command to Row DoubleClick

[gerardo]

Good day,

 

How can I bind/trigger a command in my ViewModel on GridView Row DoubleClick. Is there a way I can bind it without codebehind

 

Thanks

[Dinko | Tech Support Engineer]

Hi Gerardo,

I can suggest here to bind the PreviewMouseDoubleClick event of the RadGridView to an ICommand property using our EventToCommandBehavior. You can pass the mouse event arguments by setting the PassEventArgsToCommand property of the EventBinding to true.

<telerik:RadGridView ItemsSource="{Binding TestObjects}">
    <telerik:EventToCommandBehavior.EventBindings>
        <telerik:EventBinding EventName="PreviewMouseDoubleClick" Command="{Binding MyCommand}" PassEventArgsToCommand="True"/>
    </telerik:EventToCommandBehavior.EventBindings>
. . . . .

Then in the command executed method, you can try to get the GridViewRow.

public class MyViewModel
{
    public MyViewModel()
    {        
        MyCommand = new DelegateCommand(OnCommandExecuted);
    }

    public List<TestObject> TestObjects { get; set; }

    private void OnCommandExecuted(object obj)
    {
        var mouseButtonArgs = obj as MouseButtonEventArgs;
        var gridViewRow = (mouseButtonArgs.OriginalSource as System.Windows.UIElement).ParentOfType<GridViewRow>();
        if(gridViewRow != null)
        {
            //  my custom code
        }
    }

    public ICommand MyCommand { get; set; }
}

Regards,
Dinko
Progress Telerik

[gerardo]

This works as I needed. Thank you Sir.

[gerardo]

Hi Sir just a another question.

The above code works. But I want to apply the same approach to another GridView and pass a parameter. Since I already have the obj as MouseButtonEventArgs, can I add another commandParameter to pass a value in my command? 

 

Thank you very much

[Dinko | Tech Support Engineer]

Hello Gerardo,

You can't pass another parameter to the command. The EventToCommandBehavior does not allow this. Basically, from the MouseButtonEventArgs arguments, you should be able to get the corresponding grid and its DataContext and parent elements. You can share what you want to pass to the command so I can think of a possible solution.

Regards,
Dinko
Progress Telerik

[gerardo]

Thank you for your reply Sir.

What I am trying is to have a multiple GridView in one page. I want to use the same command for each GridView but pass another parameter to identify what condition I would use in my code depending on the GridView I double clicked.

Thank you very much.

[Dilyan Traykov]

Hello Gerardo,

My name is Dilyan and I'm stepping in for my colleague Dinko who is currently out of office.

As stated by Dinko, it is not possible to pass two parameters through the EventBinding, however, you can use properties of the RadGridView control to determine what action to perform in the command. For example, you can use the x:Name or Tag properties to achieve this.

        private void OnCommandExecuted(object obj)
        {
            var mouseButtonArgs = obj as MouseButtonEventArgs;
            var gridViewRow = (mouseButtonArgs.OriginalSource as System.Windows.UIElement).ParentOfType<GridViewRow>();
            var gridView = gridViewRow.GridViewDataControl;
            if (gridViewRow != null)
            {
                if (gridView.Name == "clubsGrid")
                {
                    var club = gridViewRow.DataContext as Club;
                    MessageBox.Show("Clicked club " + club.ToString());
                }
                else if (gridView.Name == "playersGrid")
                {
                    var player = gridViewRow.DataContext as Player;
                    MessageBox.Show("Clicked player " + player.ToString());
                }
            }
        }

If you use these properties for something else and cannot set unique values to them, you can create additional attached properties and use those.

For your convenience, I've prepared a small sample project which demonstrates this in action. Please have a look and let me know if something similar would work for you.

Regards,
Dilyan Traykov
Progress Telerik