oval

[Ben Bush]

I tested the following code and wanted to get the message of "oval2
got hit" if I click the red one. But I always got "oval1 got hit".
from Tkinter import *
root=Tk()
canvas=Canvas(root,width=100,height=100)
canvas.pack()
a=canvas.create_oval(10,10,20,20,tags='oval1',fill ='blue')
b=canvas.create_oval(50,50,80,80,tags='oval2',fill ='red')
def myEvent(event):
if a:
print "oval1 got hit!"
else:
print "oval2 got hit"
canvas.tag_bind('oval1','<Button>',func=myEvent)
canvas.tag_bind('oval2','<Button>',func=myEvent)
root.mainloop()

[Diez B. Roggisch]

Ben Bush wrote:

I tested the following code and wanted to get the message of "oval2
got hit" if I click the red one. But I always got "oval1 got hit".
from Tkinter import *
root=Tk()
canvas=Canvas(root,width=100,height=100)
canvas.pack()
a=canvas.create_oval(10,10,20,20,tags='oval1',fill ='blue')
b=canvas.create_oval(50,50,80,80,tags='oval2',fill ='red')
def myEvent(event):
if a:

Here is your problem. a is a name, bound to some value. So - it is true,
as python semantics are that way. It would not be true if it was e.g.

False, [], {}, None, ""
What you want instead is something like

if event.source == a:
...

Please note that I don't know what event actually looks like in Tkinter,
so check the docs what actually gets passed to you.
Regards,

Diez

[Ben Bush]

On 12/4/05, Diez B. Roggisch <de***@nospam.web.de> wrote:

Ben Bush wrote:

I tested the following code and wanted to get the message of "oval2
got hit" if I click the red one. But I always got "oval1 got hit".
from Tkinter import *
root=Tk()
canvas=Canvas(root,width=100,height=100)
canvas.pack()
a=canvas.create_oval(10,10,20,20,tags='oval1',fill ='blue')
b=canvas.create_oval(50,50,80,80,tags='oval2',fill ='red')
def myEvent(event):
if a:

Here is your problem. a is a name, bound to some value. So - it is true,
as python semantics are that way. It would not be true if it was e.g.

False, [], {}, None, ""
What you want instead is something like

if event.source == a:
...

Please note that I don't know what event actually looks like in Tkinter,
so check the docs what actually gets passed to you.

got AttributeError: Event instance has no attribute 'source'

[Peter Otten]

Ben Bush wrote:

On 12/4/05, Diez B. Roggisch <de***@nospam.web.de> wrote:

Ben Bush wrote:

> I tested the following code and wanted to get the message of "oval2
> got hit" if I click the red one. But I always got "oval1 got hit".
> from Tkinter import *
> root=Tk()
> canvas=Canvas(root,width=100,height=100)
> canvas.pack()
> a=canvas.create_oval(10,10,20,20,tags='oval1',fill ='blue')
> b=canvas.create_oval(50,50,80,80,tags='oval2',fill ='red')
> def myEvent(event):
> if a:

Here is your problem. a is a name, bound to some value. So - it is true,
as python semantics are that way. It would not be true if it was e.g.

False, [], {}, None, ""
What you want instead is something like

if event.source == a:
...

Please note that I don't know what event actually looks like in Tkinter,
so check the docs what actually gets passed to you.

got AttributeError: Event instance has no attribute 'source'

Note that Diez said /something/ /like/ /event.source/. The source is
actually called widget -- but that doesn't help as it denotes the canvas as
a whole, not the individual shape.

The following should work if you want one handler for all shapes:

def handler(event):
print event.widget.gettags("current")[0], "got hit"
canvas.tag_bind('oval1', '<Button>', handler)
canvas.tag_bind('oval2', '<Button>', handler)

I prefer one handler per shape:

def make_handler(message):
def handler(event):
print message
return handler

canvas.tag_bind('oval1', '<Button>', make_handler("oval 1 got hit"))
canvas.tag_bind('oval2', '<Button>', make_handler("oval 2 got hit"))

Peter

[Diez B. Roggisch]

>>

What you want instead is something like

if event.source == a:
...

Please note that I don't know what event actually looks like in Tkinter,
so check the docs what actually gets passed to you.

got AttributeError: Event instance has no attribute 'source'

As I said: I don'k _know_ how event actually looks like,a s I'm not a
Tkinter-expert, but I've had plenty of projects involving other
GUI-Toolkits, which work all the same in this manner. After all the
whole purposs of the event parameter is to inform you about the cause
for that event - in this case the pressing of a MB on a specific canvas
element.

But if you'd take it on you to consult the documentation as I asked you
to do, I'm pretty sure you find the proper attribute.
Regards,

Diez

[Ben Bush]

On 12/4/05, Diez B. Roggisch <de***@nospam.web.de> wrote:

What you want instead is something like

if event.source == a:
...

Please note that I don't know what event actually looks like in Tkinter,
so check the docs what actually gets passed to you.

got AttributeError: Event instance has no attribute 'source'

As I said: I don'k _know_ how event actually looks like,a s I'm not a
Tkinter-expert, but I've had plenty of projects involving other
GUI-Toolkits, which work all the same in this manner. After all the
whole purposs of the event parameter is to inform you about the cause
for that event - in this case the pressing of a MB on a specific canvas
element.

But if you'd take it on you to consult the documentation as I asked you
to do, I'm pretty sure you find the proper attribute.
Regards,

Diez
--
http://mail.python.org/mailman/listinfo/python-list

thanks anyway. The python manual for event is very brief and it is
hard for me to understand.
--
Ben Bush

[Ben Bush]

On 12/4/05, Peter Otten <__*******@web.de> wrote:

Ben Bush wrote:

On 12/4/05, Diez B. Roggisch <de***@nospam.web.de> wrote:

Ben Bush wrote:
> I tested the following code and wanted to get the message of "oval2
> got hit" if I click the red one. But I always got "oval1 got hit".
> from Tkinter import *
> root=Tk()
> canvas=Canvas(root,width=100,height=100)
> canvas.pack()
> a=canvas.create_oval(10,10,20,20,tags='oval1',fill ='blue')
> b=canvas.create_oval(50,50,80,80,tags='oval2',fill ='red')
> def myEvent(event):
> if a:

Here is your problem. a is a name, bound to some value. So - it is true,
as python semantics are that way. It would not be true if it was e.g.

False, [], {}, None, ""
What you want instead is something like

if event.source == a:
...

Please note that I don't know what event actually looks like in Tkinter,
so check the docs what actually gets passed to you.

got AttributeError: Event instance has no attribute 'source'

Note that Diez said /something/ /like/ /event.source/. The source is
actually called widget -- but that doesn't help as it denotes the canvas as
a whole, not the individual shape.

The following should work if you want one handler for all shapes:

def handler(event):
print event.widget.gettags("current")[0], "got hit"
canvas.tag_bind('oval1', '<Button>', handler)
canvas.tag_bind('oval2', '<Button>', handler)

I prefer one handler per shape:

def make_handler(message):
def handler(event):
print message
return handler

canvas.tag_bind('oval1', '<Button>', make_handler("oval 1 got hit"))
canvas.tag_bind('oval2', '<Button>', make_handler("oval 2 got hit"))

Peter

--
http://mail.python.org/mailman/listinfo/python-list

Peter,
It works. Thanks!
is there any good material to read if I want to improve my
understanding of working on interactive ways of dealing with shapes
on the TKinter?
--
Ben Bush

[Peter Otten]

Ben Bush wrote:

is there any good material to read if I want to improve my
understanding of working on interactive ways of dealing with shapes
on the TKinter?

See http://wiki.python.org/moin/TkInter for a list of references.
For me John Shipman's Tkinter Reference is normally sufficient.

Peter