/// <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)); }