574702 - Dragging the window through glass areas gets jumpy

Status: RESOLVED FIXED

(Toolkit :: UI Widgets, defect)

Description

[:Felipe Gomes (needinfo for replies!)]

Attachment: Avoid starting the draggable component more than once on each element

Follow-up from bug 555081. Since we apply/unapply the binding that makes glass areas draggable depending on theme/tabs-on-top, the mouse listeners might end up being added more than once. When the mouse moves, two or more events are queued with the X/Y information. When the first event is processed, the window is correctly moved, and then the following events have wrong offset information and ends up moving the window again, with incorrect deltas.

STR:
  - with latest nightly, change the visibility of menubar/app-button back and forth at least twice.
  - try dragging the window through the glass area of the menu bar

Comment 1

[Dão Gottwald [:dao]]

Is this still working around the missing destructor? Would this be fixed by bug 83635, which is blocking beta2?

Comment 2

[:Felipe Gomes (needinfo for replies!)]

The patch that works around the missing destructor hasn't landed yet. I believe that bug 83635 will make it possible to get rid of the workaround, but it's hard to tell as there's no WIP fix there that I could try. I'll keep an eye on it and be sure to test that when 83635 is fixed.

Comment 3

[[not reading bugmail]]

In Reply to Filipe:

I see this when having a unmaximized window.  And after I open the browser I was testing just dragging the window around the screen from top to bottom, side to side.  I didn't check the CPU usage there.

Comment 4

[:Felipe Gomes (needinfo for replies!)]

Dale: yeah at first I thought it was just slowness that made the window jump, but I found the problem after you customize the menu off and on again. You said that it happened only at the menubar, right? Can you confirm that you have tweaked the settings to hide and show the menu bar, and then the problem appeared? Or can you see this in an entire fresh window that has never been customized?

(The patch here should fix this if that's the case)

Comment 5

[[not reading bugmail]]

I tried the tab bar area too, though trying to confirm the rest.

Comment 6

[:Gavin Sharp [email: [e-mail]]]

https://hg.mozilla.org/mozilla-central/rev/8790aa3006fc

Comment 7

[Dão Gottwald [:dao]]

We should file a bug on using a destructor and getting rid of these workarounds.