In my quest to develop a gui generator, I have reached a stage in which I need to provide the user the ability to explore widgets placement and do a quick and easy form layout design. Same idea as some of us are already familiar with within Visual Basic and C++. The code presented here is a simplified version in order to be able to share it with a wider tcl/tk community, from newbie to guru.
The code as presented is developed in & for (yes, the tool is creating itself) tG2 v1.06.01
Some limitations which have already been solved in tG2:
- the titlebar height and framewidth of a toplevel is assumed fixed - when widgets are placed in frames, it will create another offset which needs to be taken into account, recursively...
The presented code is tested with tcl/tk v8.4.19 & WinXP OS.
# ------------------------------------------------------------------------------
bind . <Configure> {set components(geo) [split [split [wm geometry .] "x"] "+"]}
# ------------------------------------------------------------------------------
bind . <Motion> {
if {$components(moveObject) != ""} {
place $components(moveObject) \
-x [expr [winfo pointerx .] - [lindex $components(geo) 1] - 3 - $objectXoff] \
-y [expr [winfo pointery .] - [lindex $components(geo) 2] - 29 - $objectYoff]
}
}
# ------------------------------------------------------------------------------
proc makeMovableObject {w} {
set cmd "bind $w <Motion> \{$w config -cursor crosshair\}"; eval $cmd
set cmd "bind $w <Leave> \{$w config -cursor \"\"\}"; eval $cmd
set cmd "bind $w <ButtonPress-1> \{+;
set objectXoff \[expr %x]
set objectYoff \[expr %y]
set components(moveObject) $w
eval \[bind . <Motion>\]
\}"
eval $cmd
bind $w <ButtonRelease-1> {+;
set components(moveObject) ""
}
}
set components(moveObject) ""
eval [bind . <Configure>]
# ---------------------------------- TEST CODE ---------------------------------
button .button1 -text "hello world"
place .button1 -x 50 -y 50
makeMovableObject .button1
label .label1 -text "hello again"
place .label1 -x 50 -y 80
makeMovableObject .label1