/// <summary>
/// Enables an external user-interface handler.
/// </summary>
/// <param name="installUIHandler">Specifies a callback function.</param>
/// <param name="messageFilter">Specifies which messages to handle using the external message handler.</param>
/// <param name="context">Pointer to an application context that is passed to the callback function.</param>
/// <returns>The return value is the previously set external handler, or null if there was no previously set handler.</returns>
internal static InstallUIHandler SetExternalUI(InstallUIHandler installUIHandler, int messageFilter, IntPtr context)
{
return(MsiInterop.MsiSetExternalUI(installUIHandler, messageFilter, context));
}