Using settings dialogs requires a bit more setup. The most important thing to remember is that the &xcenter; does not invoke a settings dialog on an open &xcenter; widget, but on a setup string only.

This was done so that settings dialogs can be displayed for a widget even if that widget is not currently visible (i.e. doesn't currently exist as a window). This allows the &xcenter; to display the settings dialog from both the "Properties" menu item in a widget's context menu and from a widget's context menu on the "Widgets" page in the &xcenter; settings notebook -- even if the &xcenter; isn't currently open.

Basically, to support settings dialogs, your widget class must do the following:

1. In the widget class definition (XCENTERWIDGETCLASS), set the pShowSettingsDlg field to the function in your DLL which can display the settings dialog.

   This function must have the following prototype:

   typedef VOID EXPENTRY ShowSettingsDialog(PWIDGETSETTINGSDLGDATA pData);

2. When the &xcenter; needs to invoke the settings dialog (e.g. because the "Properties" menu item was selected), it will call exactly this function, which should do a standard WinDlgBox and not return until the dialog has been dismissed ("OK" or "Cancel" were pressed).

   That function receives a pointer to a temporary WIDGETSETTINGSDLGDATA structure, which the &xcenter; has composed for the settings dialog. In there, the settings dialog can find out whether the widget is currently visible.