adavis I am developing an application which requires a third mouse button; However, the two button mouse seems by far to be the most common variety. I've put together something which emulates a third mouse button by pressing both mouse buttons together. I've searched but haven't found an existing solution, though I guess there must be one, so I'm posting my version. It seems to work OK but I presume there is a neater solution...
I've decided to call the system button13 which generates the following virtual events:-
Buttons one and three must be pressed within 200ms of each other (This value can be set as a parameter).
proc button13 {widget {ms 200}} {
bind $widget <Button-1> "button13proc1 $widget 1 $ms"
bind $widget <Button-3> "button13proc1 $widget 3 $ms"
}
proc button13proc1 {widget button ms} {
global button13
if {[info exists button13($widget)] && ! [string equal $button13($widget) $button]} {
event generate $widget <<Button-13>>
catch "unset button13($widget)"
return
}
set button13($widget) $button
after $ms "button13proc2 $widget $button"
}
proc button13proc2 {widget button} {
global button13
if {! [info exists button13($widget)]} {
return
}
if {[info exists button13($widget)] && ! [string equal $button13($widget) $button]} {
event generate $widget <<Button-13>>
} else {
event generate $widget <<Button-$button>>
}
catch "unset button13($widget)"
}
#===================#
# Example of usage. #
#===================#
label .lab1 -text "Click on this label"
button13 .lab1
bind .lab1 <<Button-1>> "puts Button-1"
bind .lab1 <<Button-3>> "puts Button-3"
bind .lab1 <<Button-13>> "puts Button-13"
pack .lab1