Radiobutton Entries
- Preface
- Introduction
- Tutorial
- Implementation
- Commands
- bitmap
- eval-wish
- get-tk-var
- photo
- set-tk-var!
- tk
- tk-id->widget
- tk-var
- tk/after
- tk/appname
- tk/bind
- tk/bindtags
- tk/caret
- tk/choosecolor
- tk/choosedirectory
- tk/clipboard
- tk/console
- tk/destroy
- tk/dialog
- tk/event
- tk/focus
- tk/getopenfile
- tk/getsavefile
- tk/grab
- tk/grid
- tk/image
- tk/lower
- tk/messagebox
- tk/option
- tk/pack
- tk/place
- tk/popup
- tk/raise
- tk/scaling
- tk/update
- tk/useinputmethods
- tk/wait
- tk/windowingsystem
- tk/winfo
- tk/wm
- Options
- Extensions
- Changes
A radiobutton menu entry behaves much like a radiobutton widget.
Radiobutton entries are organized in groups of which only one entry may be selected at a time. Whenever a particular entry becomes selected it stores a particular value into a particular global variable (as determined by the #:value and #:variable options for the entry). This action causes any previously-selected entry in the same group to deselect itself. Once an entry has become selected, any change to the entry's associated variable will cause the entry to deselect itself.
Grouping of radiobutton entries is determined by their associated variables: if two entries have the same associated variable then they are in the same group. An indicator diamond is displayed to the left of the label in each radiobutton entry.
If the entry is selected then the indicator's center is displayed in the color given by the #:selectcolor option for the entry; otherwise the indicator's center is displayed in the background color for the menu.
If a #:command option is specified for a radiobutton entry, then its value (which is a lambda expression) each time the entry is invoked; this happens after selecting the entry.