Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Terry Reedy <tjreedy@udel.edu>
Newsgroups: comp.lang.python
Subject: Re: Resources/pointers for writing maintable, testable Python
Date: Thu, 19 May 2016 18:45:30 -0400
Lines: 67
Message-ID: <mailman.44.1463697947.27390.python-list@python.org>
References: <CA+yM-qbQSUKy8f3K1OF0-ON0mU7UugPLVnSkxXENkFes2SYQkA@mail.gmail.com> <CA+y5TLaDATkWELXdESMMYfmhJKNLiDJjGEbTDYYSRYTZqws4GA@mail.gmail.com> <mailman.22.1463608092.27390.python-list@python.org> <ffa86da4-f7f1-4a02-9fba-0bd6ca68e074@googlegroups.com> <nhkpa0$crf$1@ger.gmane.org> <mailman.35.1463675017.27390.python-list@python.org> <909ee5e9-ae16-4ebe-a6c1-c838ff3bb8fd@googlegroups.com> <nhlfmb$n5p$1@ger.gmane.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: quoted-printable
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0
In-Reply-To: <909ee5e9-ae16-4ebe-a6c1-c838ff3bb8fd@googlegroups.com>
Precedence: list
Xref: csiph.com comp.lang.python:108847

On 5/19/2016 4:10 PM, Mike Driscoll wrote:
> On Thursday, May 19, 2016 at 11:23:53 AM UTC-5, Terry Reedy wrote:

>> In my case, I learned better how to test IDLE from a user perspective.=

>> For tkinter apps, an external program such as Selenium is not needed.
>> Tk/tkinter have the simulated event generation and introspection neede=
d
>> to simulate a user hitting keys, clicking mouse buttons, and reading t=
he
>> screen.

> I am curious. Where is this documented? Are you referring to calling
 > the invoke() method on each widget?

For widget commands, yes.  (And thanks for reminding of the method.)

For events:
http://infohost.nmt.edu/tcc/help/pubs/tkinter/web/universal.html
(An indispensible tkinter reference) says:
'''
w.event_generate(sequence, **kw)

     This method causes an event to trigger without any external=20
stimulus. The handling of the event is the same as if it had been=20
triggered by an external stimulus. The sequence argument describes the=20
event to be triggered. You can set values for selected fields in the=20
Event object by providing keyword=3Dvalue arguments, where the keyword=20
specifies the name of a field in the Event object.

     See Section 54, =E2=80=9CEvents=E2=80=9D for a full discussion of ev=
ents.
'''
This omits some essentials.  tcl.tk/man/tcl8.6/TkCmd/event.htm
has much more, including the need to put focus on Text and Entry.

 From Stackoverflow, I learned that .update() is needed *before*=20
=2Eevent_generate.  The following works.

import tkinter as tk
root =3D tk.Tk()
def prt():
     print('Handler called')
button =3D tk.Button(root, text=3D'Click', command=3Dprt)
button.place(x=3D20, y=3D20)
def ev(e):
     print(e.x, e.y)
button.bind('<ButtonPress-1>', ev)
button.update()
button.event_generate('<ButtonPress-1>', x=3D0, y=3D0)
button.event_generate('<ButtonRelease-1>')
button.invoke()
entry=3Dtk.Entry(root)
entry.place(x=3D20, y=3D50)
entry.focus_force()
entry.update()
entry.event_generate('<Key-a>')

The event is reported, the handler is called, and 'a' is inserted.=20
(Inserting text could be done more easily, but some key events such as=20
<Key-End> do have text equivalents.)

--=20
Terry Jan Reedy