Menu Types and Rules

Forms may have a bar menu gadget or main menu, which appears as a row of options across the top of the form. When you select one of the menu options, a pull-down menu is temporarily displayed. Fields on a menu may have pull-right arrows (>) that open a pull-down sub-menu when selected.

Forms and gadgets can have popup menus assigned to them. When you move the cursor onto them and press the mouse popup button, the menu pops-up at the cursor and you can then select from the displayed options.

The following rules determine how you can use menus:

• Each menu belongs either to the Main menu system or to the Popup menu system, but cannot belong to both.

• A menu in the Main system can appear only once. i.e. it cannot be a sub-menu of several menus.

• A menu in the Popup system may appear only once in a given popup tree, but may be used in any number of popup trees.

• A menu cannot reference itself, either directly as a pullright of one of its own fields or be a pullright of another menu in its own menu tree.

• Any pullright field of a menu references a sub-menu that will be inferred to be of the same type as the referencing menu.

Hints and Tips for Using Menu Types

In general:

• It is not necessary to specify the menu usage type on a form that has only main menus (and this includes most Main forms).

• It is always necessary to specify the usage-type for menus that are part of the POPUP menu system.

For forms that contain a mixture of main and popup menus:

• First define the bar before defining the menus.

• Next define the menus of the main system.

• Next define menus of the popup system, declaring them all as type POPUP.

• If you are dynamically creating new menus with the NewMenu() form methods, then always specify the menu type. This will maximise the system’s chance of alerting you to any errors.

Core-Code Based Menus

AVEVA developers can define core managed PML menu fields. Refer to Form Core Support for further information.