Question

Still writing a game. This error’s a little different, though. I get a trace back like this…

Exception in Tkinter callback
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/3.1/lib/python3.1/tkinter/__init__.py",
line 1399, in __call__
return self.func(*args)
File "/Users/bluedragon1223/Desktop/Djambi0-2.py", line 68, in _newSpaceChosen
pieceID = event.widget.find_withtag(currentCommand)
File "/Library/Frameworks/Python.framework/Versions/3.1/lib/python3.1/tkinte/__init__.py",
line2199, in find_withtag
return self.find('withtag', tagOrId)
File "/Library/Frameworks/Python.framework/Versions/3.1/lib/python3.1/tkinter/__init__.py",
line 2173, in find
self.tk.call((self._w, 'find') + args)) or ()
_tkinter.TclError: wrong # args: should be ".23215664 find withtag tagOrId"

I mean, I thought the code innocuous enough.

I have global variables currentCommand = None and (CurX, CurY) = (0,0) and (ToX, ToY) = (0,0) to start with, if that has something to do with it, but the main problem is my events.

There are two:

def _newSpaceChosen(event):
print(event.widget.find_withtag('rN')) #Used to check if I had used find_withtag correctly
pieceID = event.widget.find_withtag(currentCommand) #This is the problem source
[CurX, CurY] = event.widget.coords(pieceID[1])
print(CurX, CurY)
[MetaToX, MetaToY] = _point2square(event.x, event.y)
print(event.x, event.y)
print(MetaToX, MetaToY)
[ToX, ToY] = _square2point(MetaToX, MetaToY)
print(ToX, ToY)
event.widget.move(pieceID, ToX - CurX, ToY - CurY)

def _onPieceClick(event):
stuffTags = event.widget.gettags(event.widget.find_closest(event.x, event.y))
try:
    event.widget.delete(event.widget.find_withtag('bbox'))
except:
    pass
bboxULX = (event.x // 90 + 1) * 90
bboxULY = (event.y // 90 + 1) * 90 
bboxLRX = (event.x // 90 + 1) * 90 - 90
bboxLRY = (event.y // 90 + 1) * 90 - 90
event.widget.create_rectangle(bboxULX,bboxULY,bboxLRX,bboxLRY, width=3,   
outline='yellow',tag='bbox')
currentCommand = stuffTags[0]
print(currentCommand)`

The idea was to store the game piece tag in currentCommand, and then use that value to control that specific piece until the piece was moved with bindings like this:

canvas.bind('<1>', _newSpaceChosen)

in the def __init__(self, mainWin): of a class Board(Canvas):
Each piece has it’s own tag_bind(#piece-var, '<1>', _onPieceClick)

My hypothesis is that currentCommand is not receiving a value soon enough.
What do you guys think causes this trace?

Answer 1

Your hypothesis is almost certainly correct. You can easily test this hypothesis by printing out the value before calling find_withtag.