Re: [matplotlib-devel] RFC: double click support in matplotlib

[Daniel H. <dh...@gm...>]

I added double click support in, here in the following issue report:

https://github.com/matplotlib/matplotlib/issues/550

I did use the extra flag in MouseEvent, but I can change this to a
separate event if all think that it is appropriate; I still favor the
flag for backwards compatibility.  All backends are done except for
cocoagg; see the issue report above for details.

On Sat, Oct 22, 2011 at 10:57 PM, Benjamin Root <ben...@ou...> wrote:
>
>
> On Saturday, October 22, 2011, Daniel Hyams <dh...@gm...> wrote:
>> matplotlib doesn't support double clicks, and I was wondering if that
>> was a design decision, or something that had been relegated to the "to
>> do" box for someday. Hoping that it was still in the "todo" box, I
>> think I can put most of it in without too much trouble, and supply you
>> with a patch.
>>
>> The changes would be:
>>  1) an extra flag MouseEvent, so that in a button_press_event
>> handler, you can can tell if the press was a result of a double click
>> or not, and
>>  2) code in the backends to catch and set the double click flag properly
>>
>> I looked through the backends, and it was clear what to do in order to
>> support double clicks for all but backend_macosx.py.  I might be able
>> to deduce what to do there, but will likely need some support from
>> someone in order to get that one done.
>>
>> To support the double clicks, I would rather not create a new event
>> like 'button_doubleclick_event', for backwards compatibility.  I
>> believe that if we just stick with 'button_press_event' and set an
>> extra flag within the MouseEvent, any existing mpl code will still
>> work properly, because the normal sequence of events on a double click
>> are; DOWN, UP, DBLCLICK, UP.  In current versions of matplotlib, the
>> DBLCLICK event is treated as a DOWN, and the strategy of just adding a
>> extra flag in MouseEvent would mean that existing mpl code would still
>> see the double click event as a DOWN.
>>
>> Anyway, I want to "throw a feeler" out there, and ask if the patch
>> would be accepted were I to go ahead and do it. I didn't want to spend
>> the time working on it if a decision had already been made a while
>> back to not ever support double clicks.
>>
>
> My vote would be yes, but I think i would want it as a separate event.
>  Consider some of the widgets like lasso and the zoom bbox.  If one were to
> attach a button_press_event for the purpose of detecting double clicks, I
> would imagine that there may exist conflicts (or those widget codes would
> have to be adjusted to exclusively respond only to single clicks).  Would
> existing widgets also fire even if a double-click occured?
>
> My 2 cents,
> Ben Rootl



-- 
Daniel Hyams
dh...@gm...