Taskbar (Shell_TrayWnd) Alignment of items using Win32 API

Question

Currently, I have a problem with changing the alignment of items such as Start Button, Search, Pinned items.

I wrote code, which works in a Console Application, but it won't work in a WinUI 3 or UWP Packaged Desktop application because of restrictions which will not give me a permission to update the registry.

Here's sample of code:

public static void SetTaskbarAlignment(bool isCentered)
{
    using var key = Registry.CurrentUser.OpenSubKey(@"Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced", true);

    if (key is not null)
    {
        var value = isCentered ? 1 : 0;

        key.SetValue("TaskbarAl", value, RegistryValueKind.DWord);
    }
}

Is there other way to change Taskbar Alignment using Win32 API and not changing registry in a process?

Answer 1

The setting you're trying to change is a setting that controls the behavior of the shell for the current user. If a sandbox app, like your UWP app, was able to do that then it wouldn't be much of a sandbox. The whole purpose of running an app in a sandbox in UWP is so it cannot make changes that the user doesn't authorize. Changing the taskbar alignment would be such a change.

If you need to make a shell change for the user then you're going to need to request permission for your app to do it via the registry. I'm not aware of a Win32 API to do it but even if there were then your UWP app would either not have access (because it is a sandbox) or you'd have to ask for permissions to whatever rights it is tied to.