Progress
Programming
Handbook


Combo Boxes

A combo box consists of a fill-in field or variable, a button, and a selection list. A combo box can display any single value from the selection list in the fill-in field. This single value can also be assigned to the underlying field or variable.

Progress provides the following types of combo-box widgets:

You can use the combo–box widget with a CHARACTER, INTEGER, DECIMAL, LOGICAL, or DATE field or variable. The value representations in the drop-down list conform to the data type of the underlying field or variable. Like radio sets and selection lists, combo boxes are useful for representing fields or variables that have a limited number of possible values. One advantage of combo boxes is that they take up less screen space than radio sets and selection lists.

The end user can position to a value in the drop-down list by using the arrow keys in all interfaces, or in graphical interfaces by using the scroll bar.

To select a value in the character interface, the end user can position to the value in the drop-down list using the arrow keys and press SPACEBAR or RETURN to confirm the selection.

To select a value in the graphical interface, the end user can apply the following techniques:

When the user selects an item, it triggers the VALUE–CHANGED event.

Thus, a combo box combines the functionality of a fill-in field, selection list, and radio set. It uses a fill-in field to display the selected item, and like a selection list displays a list of available values. Like a radio set, it supports sets of values for any Progress data type and allows selection of any one value at a time.


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