DispatcherQueue.TryEnQueue() will execute the callback multiple times

[zxmfzx]

Describe the bug

TextBox.Text += string in a sub-thread (created using the Thread class) using the DispatcherQueue.TryEnQueue() function then this string will be added multiple times. Using a breakpoint, I found that the re-callback, i.e., the Lambda function, was executed multiple times, but TryEnQueue() was executed only once

Steps to reproduce the bug

parent.DispatcherQueue.TryEnqueue( () => {

        parent.text_log.Text += "ABCDEFGHI" 
            + System.Environment.NewLine;
}
);

Expected behavior

The callback should only run once

Screenshots

No response

NuGet package version

None

Packaging type

No response

Windows version

No response

IDE

No response

Additional context

No response

[DarranRowe]

I personally don't see this.

While it is a C++ application, the code that I used was:

    void MainWindow::Click_Click(winrt::IInspectable const &, winrt::RoutedEventArgs const &)
    {
        std::thread t([this]()
            {
                auto dq = DispatcherQueue();
                dq.TryEnqueue([this]()
                    {
                        auto current_text = OutText().Text();
                        OutText().Text(current_text + L"ABCDEF");
                    });
            });

        t.detach();
    }

This was a regular WinUI 3 application.

https://github.com/microsoft/WindowsAppSDK/assets/52577874/23f100f2-cbef-417f-828d-58b5b68f0e00

You can see from this video that it only appends the text once. Could you provide a sample that reproduces this problem?

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This issue has been automatically marked as stale because it has been marked as requiring author feedback but has not had any activity for 7 days. It will be closed if no further activity occurs within 7 days of this comment.