How Forms are Loaded and Displayed

A form definition must be loaded before the form can be displayed. If you have stored the definition in a .pmlfrm file then loading will be automatic when the form is displayed for the first time.

Normally, a form is displayed as a result of the operator making a menu selection or pressing a button on a form. This is achieved either by using the Form Directive in the menu or button definition (see next section) or by means of the command show !!formname used in the callback of the gadget.

However, to display forms when you are developing them, you may find it convenient to type the command:

show !!formname

Sometimes it is useful to force the loading of the definition file of a form before the form is actually displayed, so that you can edit the form or gadget attributes from the callbacks of another form before the form is actually displayed. Using the following command from a callback will force load the definition if the form is unknown to PML, but do nothing if the form has already been loaded.

loadform !!formname

Once a form has been displayed, you can remove it from the screen using the command:

hide !!formname

Note:
If you show it again, it will appear on the screen but its definition is already known to PML and so it will not be loaded.

It is possible to remove a form definition from PML using the following command:

kill !!formname

The form is then no longer known to PML until a new definition is loaded.

Note:
Earlier AppWare used form definitions in macro files which had to be loaded explicitly via $M path-name-to-file. This mechanism still operates for backwards compatibility, but is strongly discouraged when writing new AppWare.