COMMAND [KEY()] "option" block
The COMMAND [KEY(key-name)]
"option-name"
clause defines a menu action handler with a set
of instructions to be executed when an action is invoked. The option text (option-name
),
converted to lowercase letters, defines the name of the action.
For example, when defining:
COMMAND "Hello"
The name of the action will be "hello
" (not "Hello
"
with a capital H).
When used with the KEY()
clause, the command specifies both accelerator keys
and an option
text.
Action defaults will be applied by using the action name defined by the option text (converted to lowercase).
In TUI mode, actions created with COMMAND [KEY]
do not get accelerators from
action defaults; only actions defined with ON ACTION
will get accelerators of
action defaults.
Explicit action views defined in the form (BUTTON
in layout,
TOPMENU
or TOOLBAR
items) will get all action defaults associated
to the menu command, while default action views (i.e. buttons in the action frame) will be decorated
with the menu option text and comment specified in the program (this means that the
TEXT
and COMMENT
attributes of the corresponding action defaults
entry are not used for the default action views). However, other attributes such as the
IMAGE
will also be applied to default action views.
COMMAND "Hello" "This is the Hello option"
The
name of the action will become "hello
", the default action view button text will be
"Hello
", and the button hint will be "This is the Hello option
",
even if an action default defines a different text or comment for the "hello
"
action. If the corresponding action default defines an IMAGE
icon, it will display
in the default action view button.COMMAND
menu clause can be used as
default accelerator, if no other accelerator is defined by a KEY()
clause or by
action defaults:- When the menu option is not rendered as a default view and is bound to an action
view like a toolbar button, the first letter of the
COMMAND
option will define the default accelerator, except if several menuCOMMAND
options start with the same letter, or if the letter is used as accelerator by another command. - When the menu option is rendered as a default view, and the first letter of a menu
COMMAND
option is not used by other menu option labels, pressing the key corresponding to that letter will execute that action. If several menuCOMMAND
options start with the same letter and the user presses that key, the front-end shifts the focus from button to button. To fire the action, the user must press ENTER.
When using an ampersand (&) in the command name, some front-ends consider the letter
following & as an Alt-key accelerator, and the letter will be underscored. The ampersand
character forms part of the action name. For example, COMMAND "&Save"
will
create an action with the name "&save
".
In a MENU
instruction, the alternative to COMMAND [KEY]
"option-name"
can be the ON ACTION action-name
clause,
to write abstract code without having the decoration (option name, comment and accelerators) in the
program code.