Hi
If you want to use the checkbox, then you could change the way it works
The below code, substituted in pyvcp_widgets.py, will create an extra IN pin called pyvcp.{whateveryounamedcheckbox}.changepin
It toggles the state of the checkbox, when set TRUE.
(it will not toggle again until pin goes FALSE to prevent a race condition)
Activating will either check or uncheck the checkbox, depending upon its current state, user click on the checkbox will revert the state.
Code:
class pyvcp_checkbutton(Checkbutton):
""" (control) a check button
halpin is 1 when button checked, 0 otherwise
<checkbutton>
[ <halpin>"my-checkbutton"</halpin> ]
[ <text>"Name of Button"</text>] text set in widget
[ <initval>1</initval> ] sets intial value to 1, all values >=0.5 are assumed to be 1
</checkbutton>
"""
n=0
def __init__(self,master,pycomp,halpin=None,initval=0,**kw):
self.v = BooleanVar(master)
Checkbutton.__init__(self,master,variable=self.v,onvalue=1, offvalue=0,**kw)
if halpin == None:
halpin = "checkbutton."+str(pyvcp_checkbutton.n)
self.halpin=halpin
pycomp.newpin(halpin, HAL_BIT, HAL_OUT)
changepin = halpin + ".changepin"
self.changepin=changepin
pycomp.newpin(changepin, HAL_BIT, HAL_IN)
pycomp[self.changepin] = 0
pyvcp_checkbutton.n += 1
if initval >= 0.5:
self.value=1
else:
self.value=0
self.v.set(self.value)
self.reset = 0
def update(self,pycomp):
# prevent race condition if connected to permanently on pin
if pycomp[self.changepin] and not(self.reset):
self.v.set(not(self.v.get()))
self.reset = 1
pycomp[self.changepin] = 0 # try to reset, but may not work
if not(pycomp[self.changepin]) and(self.reset):
self.reset = 0
pycomp[self.changepin] = 0 # make sure is reset now
pycomp[self.halpin]=self.v.get()
As with all parsel-tongue, be very careful of indentation if you cut and paste this
You can amend to suit.
For instance: if you will only ever want to uncheck the box, just change the conditional test in update()
so that it only toggles the value in self.v if that value is true.
regards
EDIT added another reset of IN pin to ensure it is done, whatever the result of the conditional test
