Better wrap handlers

[WebFreak001]

Should always accept D delegates, also in setters

[Rayerd]

Are you referring to being able to pass the cancelEvent as a dlang delegate, for example in the following code?

// Show message dialog.
auto msgDlg = MessageDialog.New(hstring("show").handle, hstring("Hello D/WinRT").handle);
msgDlg.as!IInitializeWithWindow.Initialize(handle);
auto okEvent = event!(UICommandInvokedHandler, Windows.UI.Popups.IUICommand)(
	(Windows.UI.Popups.IUICommand command) {
		msgBox("It's OK.");
	}
);
// auto cancelEvent = handler!UICommandInvokedHandler(
// 	(Windows.UI.Popups.IUICommand command) {
// 		msgBox("It's cancel.");
// 	}
// );
auto cancelEvent = (Windows.UI.Popups.IUICommand command) {
	msgBox("It's cancel.");
};
auto command1 = UICommand.New(hstring("OK").handle, okEvent); // ok
auto command2 = UICommand.New(hstring("Cancel").handle, cancelEvent); // Compile Error

[WebFreak001]

yes

[Rayerd]

Currently, most interface methods are defined as extern(Windows). However, for interfaces like MessageDialog, where not all methods in the projection code are COM interface methods, extern(D) is sufficient. By defining some static methods as extern(D), you can pass dlang delegates directly to event handlers. What do you think?

[Rayerd]

https://github.com/Rayerd/dwinrt/tree/better_wrap_handler
It's the experimental branch for this issue.
Sample code for usage:

// Get notify XML template.
XmlDocument toastXml = ToastNotificationManager.GetTemplateContent(ToastTemplateType.ToastText01);

// Create text node.
XmlNodeList stringElements = toastXml.GetElementsByTagName("text");
XmlText textNode = stringElements.Item(0).as!XmlText;
XmlText newTextNode = toastXml.CreateTextNode("This is the message from dlang!");
textNode.AppendChild(newTextNode);

// Create notifier object.
wstring str_appid = "dfl.toast_example";
ToastNotifier notifier = ToastNotificationManager.CreateToastNotifier(str_appid);

// Create ToastNotification object.
ToastNotification toast = ToastNotification.New(toastXml);
notifier.Show(toast);

// Show message dialog.
auto msgDlg = MessageDialog.New("show", "Hello D/WinRT");
msgDlg.as!IInitializeWithWindow.Initialize(handle);
auto okEvent = delegate (IUICommand command) { // accept D delegate
	msgBox("It's OK.");
};
auto cancelEvent = delegate (IUICommand command) { // accept D delegate
	msgBox("It's cancel.");
};
auto command1 = UICommand.New("OK", okEvent);
auto command2 = UICommand.New("Cancel", cancelEvent);
msgDlg.Commands.abi_Append(command1);
msgDlg.Commands.abi_Append(command2);
msgDlg.DefaultCommandIndex = 0;
msgDlg.CancelCommandIndex = 1;

// Another method for button-clicked event.
msgDlg.ShowAsync.then(
	(IUICommand thisCommand) {
		if (thisCommand is command1)
			msgBox("Completed.");
		else if (thisCommand is command2)
			msgBox("Cancled.");
	}
);