mouse scroll event in Gtk3 backend

[Yves33]

Hello,

as previously reported

The scoll events are not captured in the Gtk3 backend on linux.
in matplotlib / lib / matplotlib / backends / backend_gtk3.py
the event mask is incorrect

event_mask = (Gdk.EventMask.BUTTON_PRESS_MASK |
Gdk.EventMask.BUTTON_RELEASE_MASK |
Gdk.EventMask.EXPOSURE_MASK |
Gdk.EventMask.KEY_PRESS_MASK |
Gdk.EventMask.KEY_RELEASE_MASK |
Gdk.EventMask.ENTER_NOTIFY_MASK |
Gdk.EventMask.LEAVE_NOTIFY_MASK |
Gdk.EventMask.POINTER_MOTION_MASK |
Gdk.EventMask.POINTER_MOTION_HINT_MASK|
Gdk.EventMask.SCROLL_MASK)

The correct event mask should be

event_mask = (Gdk.EventMask.BUTTON_PRESS_MASK   |
                  Gdk.EventMask.BUTTON_RELEASE_MASK |
                  Gdk.EventMask.SCROLL_MASK         |
                  Gdk.EventMask.EXPOSURE_MASK       |
                  Gdk.EventMask.KEY_PRESS_MASK      |
                  Gdk.EventMask.KEY_RELEASE_MASK    |
                  Gdk.EventMask.ENTER_NOTIFY_MASK   |
                  Gdk.EventMask.LEAVE_NOTIFY_MASK   |
                  Gdk.EventMask.POINTER_MOTION_MASK |
                  Gdk.EventMask.POINTER_MOTION_HINT_MASK)
(note the Gdk.EventMask.SCROLL_MASK)

thanks.

Yves

[TAC edit for markup]

[tacaswell]

Can you put in a PR (pull request) with that change?

Where was this previously reported?

[efiring]

I don't see any difference; I see Gdk.EventMask.SCROLL_MASK in both of your event_mask definitions. It is the last on the list in backend_gtk3.py, and 3rd in the list in your revised version. What am I missing?

[tacaswell]

@Yves33 any update on this?

[fariza]

I'm inclined to close this, we use the mouse scroll events in backend_tools. ZoomPanBase without any problem (Gtk3 backends).

[efiring]

Another good catch. Thanks, @fariza.