diff options
Diffstat (limited to 'ipl/gprocs/select.icn')
| -rw-r--r-- | ipl/gprocs/select.icn | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/ipl/gprocs/select.icn b/ipl/gprocs/select.icn new file mode 100644 index 0000000..9557c00 --- /dev/null +++ b/ipl/gprocs/select.icn @@ -0,0 +1,99 @@ +############################################################################ +# +# File: select.icn +# +# Subject: Procedure to get selection from window +# +# Author: Ralph E. Griswold +# +# Date: August 30, 1996 +# +############################################################################ +# +# This file is in the public domain. +# +############################################################################ +# +# +# +############################################################################ +# +# Requires: Version 9 graphics +# +############################################################################ +# +# Links: grecords +# +############################################################################ + +link grecords + +procedure select(win) #: interactive selection from window + local x0, x1, y0, y1, w, h, state, event + + /win := &window + + WAttrib(win, "drawop=reverse") + WAttrib(win, "linestyle=onoff") + + state := "wait" + + while event := Event(win) do { + if event == "q" then { + DrawRectangle(win, \x0, y0, 0, 0) # clear if already drawn + fail + } + case state of { + "wait": { # waiting for selection + case event of { + &lpress: { + x1 := x0 := &x # initial coordinates + y1 := y0 := &y + DrawRectangle(win, x0, y0, 0, 0) # start selection + state := "select" # now select the rectangle + } + } + } + "select": { # select the rectangle + case event of { + &ldrag: { # selecting ... + DrawRectangle(win, x0, y0, x1 - x0, y1 - y0) # erase + x1 := &x # new opposite corner + y1 := &y + DrawRectangle(win, x0, y0, x1 - x0, y1 - y0) # draw + } + &lrelease: { # got it! + DrawRectangle(win, x0, y0, x1 - x0, y1 - y0) # erase + x1 := &x # new opposite corner + y1 := &y + if (x0 = x1) | (y0 = y1) then # no area + state := "wait" + else { + w := x1 - x0 # set up for action + h := y1 - y0 + DrawRectangle(win, x0, y0, w, h) # draw rectangle + state := "act" # now do something + } + } + } + } + "act": { + case event of { + "n": { # new selection + state := "wait" + DrawRectangle(win, x0, y0, w, h) # try again + } + "q": { # quit + DrawRectangle(win, x0, y0, w, h) + fail + } + "r": { # return selection + DrawRectangle(win, x0, y0, w, h) # + return rect(x0, y0, w, h) + } + } + } + } + } + +end |