combobox - Create and manipulate combination box widgets

SYNOPSIS

combobox pathName ?options?

INHERITANCE

itk::Widget <- LabeledWidget <- Entryfield <- Combobox

STANDARD OPTIONS

background
foreground
insertBorderWidth
justify
selectForeground
borderWidth
highlightColor
insertOffTime
relief
textVariable
cursor
highlightThickness
insertOnTime
selectBackground
width
exportSelection
insertBackground
insertWidth
selectBorderWidth

See the "options" manual entry for details on the standard options.

ASSOCIATED OPTIONS

hscrollmode
vscrollmode
items
textBackground
textFont

See the "scrolledlistbox" manual entry for details on the above inherited options.

show
state

See the "entry" manual entry for details on the above inherited options.

INHERITED OPTIONS

childSitePos
invalid
command
textBackground
fixed
textFont
focusCommand
validate

See the "entryfield" class manual entry for details on the inherited options.

labelBitmap
labelPos
labelFont
labelText
labelImage
labelVariable
labelMargin

See the "labeledwidget" class manual entry for details on the inherited options.

WIDGET-SPECIFIC OPTIONS

Name:                   autoClear
Class:                  AutoClear
Command-Line Switch:	-autoclear

Name:                   arrowRelief
Class:                  Relief
Command-Line Switch:	-arrowrelief

Name:                   dropdown
Class:                  Dropdown
Command-Line Switch:	-dropdown

Name:                   editable
Class:                  Editable
Command-Line Switch:	-editable

Name:                   flipArrow
Class:                  FlipArrow
Command-Line Switch:	-fliparrow

Name:                   listHeight
Class:                  Height
Command-Line Switch:	-listheight

Name:                   margin
Class:                  Margin
Command-Line Switch:	-margin

Name:                   popupCursor
Class:                  Cursor
Command-Line Switch:	-popupcursor

Name:                   selectionCommand
Class:                  SelectionCommand
Command-Line Switch:	-selectioncommand

Name:                   unique
Class:                  Unique
Command-Line Switch:	-unique

DESCRIPTION

The combobox command creates an enhanced entry field widget with an optional associated label and a scrollable list. When an item is selected in the list area of a Combobox it's value is then displayed in the entry field text area. Functionally similar to an Optionmenu, the Combobox adds (optional) list scrolling and (optional) item editing and inserting capabilities.

There are two basic styles of Comboboxes (determined by the -dropdown option): dropdown and simple. The dropdown style adds an arrow button to the right of the entry field which when activated will pop up (and down) the scrolled listbox beneath the entry field. The simple (non-dropdown) Combobox permanently displays the listbox beneath the entry field and has no arrow button. Either style allows an optional entry field label.

METHODS

The combobox command creates a new Tcl command whose name is pathName. This command may be used to invoke various operations on the widget. It has the following general form:

pathName option ?arg arg ...?
Option and the args determine the exact behavior of the command. The following commands are possible for Combobox widgets:

ASSOCIATED METHODS

icursor
scan

See the "entry" manual entries for details on the above associated methods.

curselection
xview
index
yview
see
size

See the "listbox" manual entries for details on the above associated methods.

getcurselection
justify
sort

See the "scrolledlistbox" manual entries for details on the above associated methods.

WIDGET-SPECIFIC METHODS

pathName cget option
Returns the current value of the configuration option given by option. Option may have any of the values accepted by the combobox command.
pathName clear ?component?
Clears the contents from one or both components. Valid component values are list, or entry. With no component specified, both are cleared.
pathName configure ?option? ?value option value ...?
Query or modify the configuration options of the widget. If no option is specified, returns a list describing all of the available options for pathName (see Tk_ConfigureInfo for information on the format of this list). If option is specified with no value, then the command returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given widget option(s) to have the given value(s); in this case the command returns an empty string. Option may have any of the values accepted by the combobox command.
pathName delete component first ?last?
Delete one or more elements from a given component, list or entry. If a list item to be removed is currently selected (displayed in the entry field area), the entry field will be cleared.
pathName get ?index?
With no arguments, returns the contents currently in the entry field area. With a single argument, returns the contents of the listbox item at the indicated index.
pathName insert component index element ?element element ...?
Insert one or more new elements into the given component, list or entry, just before the element given by index.
pathName selection option first ?last?
Adjust the selection within the listbox component and updates the contents of the entry field component to the value of the selected item. See the "listbox" manual entry for more details on parameter options.

COMPONENTS

Name:                   entry
Class:                  Entryfield

Name:                   list
Class:                  Scrolledlistbox

DEFAULT BINDINGS

The Combobox generally has the same bindings as it's primary component items - the Scrolledlistbox and Entryfield. However it also adds these:

[1] Button-1 mouse press on the arrow key of a dropdown Combobox causes the list to be popped up. If the combobox is non-editable, a Button-1 press on the entry field area will also pop up the list.

[2] Button-1 mouse press anywhere on the display removes a dropdown listbox which has been popped up, unless the keypress is upon one of the Combobox scrollbars which scrolls the list. If it is pressed upon an item in the list area, that item will be selected before the list is removed.

[3] Button-3 mouse press on the arrow key of a dropdown Combobox causes the next item to be selected. Shift-Button-3 causes the previous item to be selected.

[4] Escape keypress removes a dropdown list which has been popped up.

[5] The <space> and <Return> keystrokes select the current item. They also remove the popped up list for dropdown comboboxes.

[6] Up and Down arrow keypresses from the entry field and arrow button component cause the previous and next items in the listbox to be selected respectively. Ctl-P and Ctl-N are similarly mapped for emacs emulation.

[7] Entry field and arrow button component Shift-Up and Shift-Down arrow keys pop up and down the listbox of a dropdown Combobox. The arrow button component also maps <Return> and <space> similarly.

EXAMPLE

 proc selectCmd {} {
    puts stdout "[.cb2 getcurselection]"
 }

 #
 # Non-editable Dropdown Combobox
 #
 combobox .cb1 -labeltext Month: \\
     -selectioncommand {puts "selected: [.cb1 getcurselection]"} \\
     -editable false -listheight 185 -popupcursor hand1 \\
     -items {Jan Feb Mar Apr May June Jul Aug Sept Oct Nov Dec}
	
 #
 # Editable Dropdown Combobox
 #
 combobox .cb2 -labeltext "Operating System:" \\
    -items {Linux HP-UX SunOS Solaris Irix} -selectioncommand selectCmd

 #
 # Simple Combobox
 #
 combobox .cb3 -labeltext Fonts: -labelpos nw \\
   -dropdown false -listheight 220 -items [exec xlsfonts]

 pack .cb1 -padx 10 -pady 10 -fill x 
 pack .cb2 -padx 10 -pady 10 -fill x
 pack .cb3 -padx 10 -pady 10 -fill x 

AUTHOR

John S. Sigler

KEYWORDS

combobox, entryfield, scrolledlistbox, itk::Widget, entry, listbox, widget, iwidgets