Fix: Fixed possible System.NullReferenceException in ThemeHelper

[yaira2]

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[hishitetsu]

Files/src/Files.App/Helpers/ThemeHelper.cs

Lines 46 to 52 in c51f7a4

	public static void Initialize()
	{
	// Save reference as this might be null when the user is in another app
	currentApplicationWindow = App.Window;
	// Set TitleBar background color
	titleBar = App.GetAppWindow(currentApplicationWindow).TitleBar;

If currentApplicationWindow is null, a NullReferenceException may occur at line 52.

[yaira2]

@hishitetsu thanks!

[hishitetsu]

If currentApplicationWindow is null here, shouldn't we try initialize again?

[yaira2]

Wouldn't it get stuck in a loop?

[hishitetsu]

We should try one time every the event raised.

[yaira2]

I'm curious what you have in mind, would you add a Boolean to keep track?

[hishitetsu]

I have like this in mind.

		private static async void UiSettings_ColorValuesChanged(UISettings sender, object args)
		{
			// Make sure we have a reference to our window so we dispatch a UI change
			if (currentApplicationWindow is null)
			{
				currentApplicationWindow = App.Window;

				if (currentApplicationWindow is not null)
					titleBar = App.GetAppWindow(currentApplicationWindow).TitleBar;
				else
					return;
			}

			// Dispatch on UI thread so that we have a current appbar to access and change
			await currentApplicationWindow.DispatcherQueue.EnqueueAsync(ApplyTheme);
		}

[yaira2]

@hishitetsu can you open a PR?