Clipboard issue

[mavaddat]

Summary

This PR fixes an issue #304 where pressing Ctrl+C inside an editable TableViewTemplateColumn cell causes a WinRT clipboard exception (CLIPBRD_E_CANT_OPEN, HRESULT 0x800401D0) to escape the control and crash the application.

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What this PR changes

1. Add exception handling around Clipboard.SetContent

(Commit: Handle clipboard exceptions)

Clipboard access can fail for normal, expected reasons. Wrapping the call in a try/catch prevents the application from crashing:

try
{
    Clipboard.SetContent(package);
}
catch (Exception ex)
{
    Debug.WriteLine($"TableView: Clipboard.SetContent failed: {ex}");
}

This matches the defensive clipboard handling used in WPF, WinForms, UWP, and other frameworks.

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2. Skip TableView‑level copy when a cell editor already handles Ctrl+C

(Commit: Skip copy on simple text fields)

When a TextBox, PasswordBox, or RichEditBox is focused, these controls already implement their own copy behavior. In such cases, TableView should not attempt to perform its own copy:

var focused = FocusManager.GetFocusedElement() as FrameworkElement;
if (focused is TextBox || focused is PasswordBox || focused is RichEditBox)
{
    return;
}

This avoids duplicate clipboard operations and prevents the control from invoking its own copy logic unnecessarily.

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Why this fix is correct

• Prevents application crashes caused by normal clipboard contention
• Preserves existing TableView copy behavior when appropriate
• Avoids interfering with built‑in editor copy behavior
• Keeps the fix localized and easy to maintain
• Does not change public API surface
• Matches defensive patterns used in other UI frameworks

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Conclusion

This PR makes WinUI.TableView more robust by:

• Preventing clipboard‑related crashes
• Respecting cell editor copy behavior
• Ensuring TableView copy logic only runs when appropriate

The changes are minimal, safe, and improve the reliability of the control in real‑world applications.

Thank you for maintaining this project — happy to adjust anything if needed.

[w-ahmad]

@mavaddat in my opinion should always skip copy operation on a template column. shouldn't we?