Futurebasic/Language/Reference/on mouse
ON MOUSE
[edit | edit source]Statement
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Syntax
[edit | edit source]ON MOUSE {FN userFunction|GOSUB{lineNumber|"stmtLabel"}}
Description
[edit | edit source]This statement designates a particular function or subroutine as a mouse-event handling routine. A mouse-event handling routine is called in response to a mouseclick which occurs inside the content region of the currently active window (but not inside any buttons, scrollbars, edit fields nor picture fields).
After such a mouseclick occurs, FB does not call your designated routine immediately. Instead, your program continues executing until a HANDLEEVENTS
statement is reached. At that time, HANDLEEVENTS
will call your designated routine once for each mouseclick event that occurred; your designated routine should examine the MOUSE <event>
functions to get information about the event.
Note:
If you use the ON MOUSE FN userFunction
syntax, then userFunction
must refer to a function which was defined or prototyped at an earlier location in the source code. Your mouse-event handling function should not take any parameters, nor return a result.
If your program does not use HANDLEEVENTS
, you can use the MOUSE(_down)
, MOUSE(_lastMVert)
, MOUSE(_lastMHorz)
and many other position functions (outlined in the FB Mouse Group of the constants document) to track mouse activity.
See Also
[edit | edit source]MOUSE <event> MOUSE(_down); MOUSE <position> HANDLEEVENTS