HIDDEN attribute

Syntax

HIDDEN [ = USER ]

1. HIDDEN sets the underlying item attribute to 1.
2. HIDDEN=USER sets the underlying item attribute to 2.

Usage

By default, all form elements are visible. Specify the HIDDEN attribute to hide a form element, such as a form field or a groupbox.

The runtime system detects hidden form fields: If you write an INPUT block using a hidden field, the field is ignored (as if it was declared as NOENTRY).

If the HIDDEN keyword is specified alone, the underlying item attribute is set to 1. The value 1 indicates that the element is definitively hidden to the end user, which cannot show the element, for example with the context menu of TABLE headers. In this hidden mode, the UNHIDABLE attribute is ignored by the front-end.

With HIDDEN=USER, the underlying item attribute is set to 2. The value 2 indicates that the element is hidden by default, but the end user can show/hide the element as needed. For example, the user can change a hidden column back to visible. Form elements like table columns that are hidden by the user might be automatically re-shown (hidden=0) by the front-end if the program dialog gives the focus to that field for input. In such case the program dialog takes precedence over the hidden attribute.

When you set a hidden attribute for a form field, the model node gets the hidden attribute, not the view node.

Form fields hidden with HIDDEN=USER (value 2) might be shown anyway, if the field is needed by a dialog for input.

Programs may also change the visibility of form elements dynamically with the ui.Form.setElementHidden() or ui.Form.setFieldHidden() methods.