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(r oot,width=100,h eight=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','<Butt on>',func=myEve nt)
canvas.tag_bind ('oval2','<Butt on>',func=myEve nt)
root.mainloop()

[Diez B. Roggisch]

Re: oval

Ben Bush wrote:[color=blue]
> 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(r oot,width=100,h eight=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:[/color]

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]

Re: oval

On 12/4/05, Diez B. Roggisch <deets@nospam.w eb.de> wrote:[color=blue]
> Ben Bush wrote:[color=green]
> > 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(r oot,width=100,h eight=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:[/color]
>
> 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.[/color]

got AttributeError: Event instance has no attribute 'source'

[Peter Otten]

Re: oval

Ben Bush wrote:
[color=blue]
> On 12/4/05, Diez B. Roggisch <deets@nospam.w eb.de> wrote:[color=green]
>> Ben Bush wrote:[color=darkred]
>> > 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(r oot,width=100,h eight=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:[/color]
>>
>> 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.[/color]
>
> got AttributeError: Event instance has no attribute 'source'[/color]

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.ge ttags("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(me ssage):
def handler(event):
print message
return handler

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

Peter

[Diez B. Roggisch]

Re: oval

>>[color=blue][color=green]
>>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.[/color]
>
>
> got AttributeError: Event instance has no attribute 'source'[/color]

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]

Re: oval

On 12/4/05, Diez B. Roggisch <deets@nospam.w eb.de> wrote:[color=blue][color=green][color=darkred]
> >>
> >>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.[/color]
> >
> >
> > got AttributeError: Event instance has no attribute 'source'[/color]
>
> 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
>[/color]
thanks anyway. The python manual for event is very brief and it is
hard for me to understand.


--
Ben Bush

[Ben Bush]

Re: oval

On 12/4/05, Peter Otten <__peter__@web. de> wrote:[color=blue]
> Ben Bush wrote:
>[color=green]
> > On 12/4/05, Diez B. Roggisch <deets@nospam.w eb.de> wrote:[color=darkred]
> >> 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(r oot,width=100,h eight=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.[/color]
> >
> > got AttributeError: Event instance has no attribute 'source'[/color]
>
> 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.ge ttags("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(me ssage):
> def handler(event):
> print message
> return handler
>
> canvas.tag_bind ('oval1', '<Button>', make_handler("o val 1 got hit"))
> canvas.tag_bind ('oval2', '<Button>', make_handler("o val 2 got hit"))
>
> Peter
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>[/color]
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]

Re: oval

Ben Bush wrote:
[color=blue]
> 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?[/color]

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

Peter