Progress
Language Reference
COMBO-BOX Phrase
Describes a combo-box widget. A combo-box represents a field or variable, and consists of a field value and an associated drop-down list of possible values.
SYNTAX
LIST-ITEMS item-list
Specifies the items to appear in the drop-down list. item-list represents a comma-separated list of valid values for the field or variable.
LIST-ITEM-PAIRS item-pair-list
Specifies a list of label-value pairs. Each pair represents the label and value of a field or variable. When the drop-down list appears, it displays each pair’s label. Then, if the user selects a label, Progress assigns the corresponding value to the field or variable. The syntax for item-pair-list is as follows:
label
A character string representing the label of the field or variable.
value
A value that Progress assigns to the field or variable if the user selects the corresponding label.
INNER-LINES lines
Specifies the number of lines visible in the drop-down list for a DROP-DOWN or DROP-DOWN-LIST combo-box widget. The value for lines must be 3 or greater. If the number of lines you specify is less than the number of items in the drop-down list, the list is scrollable.
The INNER-LINES option in a SIMPLE combo-box definition is ignored.
size-phrase
Specifies the outside dimensions (width and height) of the combo-box widget and its drop-down list using the SIZE phrase. You must specify a SIZE phrase in the definition of a SIMPLE or DROP-DOWN combo-box widget. The syntax for the SIZE phrase is as follows:
For more information, see the SIZE Phrase reference entry.
NOTE: The height value is ignored for DROP-DOWN and DROP-DOWN-LIST combo-box widgets. The height is always set to the height of a fill-in for the current font.SORT
Specifies that list items be sorted prior to display.
TOOLTIP tooltip
Allows you to define a help text message for a text field or text variable. Progress automatically displays this text when the user pauses the mouse button over a text field or text variable for which a tooltip is defined.
You can add or change the TOOLTIP option at any time. If TOOLTIP is set to “” or ? (the unknown value), then the tooltip is removed. No tooltip is the default. The TOOLTIP option is supported in Windows only.
SIMPLE
Specifies a combo-box widget with a read/write edit control and a list that is always visible. This option is supported in graphical interfaces only, and only in Windows. If you specify a SIMPLE combo-box widget in a character interface, Progress treats it as a DROP-DOWN-LIST combo-box widget.
DROP-DOWN
Specifies a combo-box widget with a read/write edit control and a drop-down list that appears when you click the drop-down button. This option is supported in graphical interfaces only, and only in Windows. If you specify a DROP-DOWN combo-box widget in a character interface, Progress treats it as a DROP-DOWN-LIST combo-box widget.
DROP-DOWN-LIST
Specifies a combo-box widget with a read-only edit control and a drop-down list that appears when you click the drop-down button. This is the default.
MAX-CHARS characters
The maximum number of characters the edit control can hold. The characters parameter must be a positive integer constant. If characters is zero or unknown (?), MAX-CHARS is set to 255 characters by default.
Use MAX-CHARS with only SIMPLE and DROP-DOWN combo-boxes. It is ignored for DROP-DOWN-LIST combo-boxes. This option is supported in graphical interfaces only, and only in Windows.
AUTO-COMPLETION
Specifies that the edit control automatically complete keyboard input to the combo-box, based on a potential match, by searching through the items in the drop-down list. This option is supported in graphical interfaces only, and only in Windows.
UNIQUE-MATCH
Specifies that the edit control complete keyboard input to the combo-box based on a unique match. This option is supported in graphical interfaces only, and only in Windows.
EXAMPLESThe first example,
r-combo.p
, views a date field as a combo-box. When you run this procedure, you can choose a date value from the drop-down list. When you choose a new value, the VALUE-CHANGED trigger updates the value of out-string to an event associated with the new date value.The example initializes the drop-down list by building a comma-separated list of values and then assigning the string to the LIST-ITEMS attribute of the combo-box.
The following example,
r-combo.p
, builds a combo-box based on field values from a database. It defines triggers that allow you to change the value of the combo-box without displaying the drop-down list. They allow you to scroll through the values using the CURSOR-DOWN and CURSOR-UP keys or to jump to a specific value by typing its first letter.
NOTES
- When the drop-down list appears, if it contains the value associated with the field or variable, that value is initially highlighted. Otherwise, no value in the drop-down list is initially highlighted.
- The LIST-ITEMS option of the COMBO-BOX phrase requires a list of items (possibly quoted, depending on the combo-box’s data type), such as ("a", "b", "c"), whereas the LIST-ITEMS attribute of a combo-box requires a quoted list of items, such as ("a, b, c"). Similarly, the LIST-ITEM-PAIRS option of the COMBO-BOX phrase requires a list of items (possibly quoted, depending on the combo-box’s data type), such as ("a", 1, "b", 2, "c", 3), whereas the LIST-ITEM-PAIRS attribute of a combo-box requires a quoted list of items, such as ("a, 1, b, 2, c, 3").
- If you do not specify the LIST-ITEMS or LIST-ITEM-PAIRS option, the screen value of the variable or field becomes the null string (" "). To display or set values in the combo-box, you must first set the LIST-ITEMS or LIST-ITEM-PAIRS attribute to assign a drop-down list that specifies the available values.
- If you specify the SORT option for a COMBO-BOX, then any items you add with the ADD-FIRST, ADD-LAST, or INSERT methods are added in sorted order rather than the order you specify.
- Windows allows the user to transfer focus to the drop-down list by pressing ALT and one of the letters in the label. This is called a mnemonic.
- When you use the SIMPLE and DROP-DOWN options to define a character-field or character-variable combo-box widget, the FORMAT string for the field or variable is ignored.
- Items in a combo-box are case insensitive.
SEE ALSO
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