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Blazor: Problem with EventCallBack in Generic component

See original GitHub issue

Describe the bug

My event is not called in the parent component when using EventCallBack in a child component. I’ve already been through #12116 and #8385 but It still not working

To Reproduce

My code: Tree.razor (child)

@typeparam TNode
<HTML WITH DOUBLECLICK EVENT>

@code{
    [Parameter] public EventCallback<DoubleClickVariableEventArgs> OnDoubleClickOnVariable { get; set; }

private void OnDoubleClickTree(object sender, MouseEventArgs e)
    {
                Console.WriteLine("TEST");
               OnDoubleClickOnVariable.InvokeAsync(new DoubleClickVariableEventArgs(selectedNode.Path, selectedNode.IsReadOnly));}
}

“TEST” is correctly displayed in the console. so the problem is from InvokeAsync.

My eventargs:

public class DoubleClickVariableEventArgs : EventArgs
    {
        public DoubleClickVariableEventArgs(string path ,bool isReadOnly)
        {
            Path = path;
            IsReadOnly = isReadOnly;
        }
        public string Path { get; private set; }
        public bool IsReadOnly { get; private set; }

    }

MAIN.razor (parent)

<Tree  TNode="TreeItem" Nodes="Items" ChildSelector="@(item => item.Childs)" @bind-SelectedNode="selectedNode" @bind-ExpandedNodes="ExpandedNodes" HasChildNodes="@(item => item.Childs?.Any() == true)" OnDoubleClickOnVariable="OnVariableDoubleClick">
                                    <TitleTemplate>@context.Text</TitleTemplate>
                                </Tree>

@code{
 private async Task OnVariableDoubleClick(DoubleClickVariableEventArgs e)
    {
        Console.WriteLine("TEST2");
}
}

I tried some of the solutions like writing the type : TNode = "TreeItem" or writing OnDoubleClickOnVariable="(DoubleClickVariableEventArgs x) => OnVariableDoubleClick(x)" Without success… I want to say that I used the exact same structure in another non-generic component and it’s working perfectly.

Further technical details

Lastest Blazor, VS Preview versions

P.S. On of my first post on github sorry if it’s unreadable

Issue Analytics

State:
Created 4 years ago
Reactions:1
Comments:5 (4 by maintainers)

Top GitHub Comments

3reactions

partyelitecommented, Dec 18, 2019

I’m having the same issue…

1reaction

javiercncommented, Nov 29, 2019

@Flearz thanks for contacting us.

@rynowak can you take a look at this and see if there’s an issue?

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