Issue 163 in los-cocos: Event order

[codesite...@google.com]

Status: New
Owner: ----

New issue 163 by mikejohnwyatt: Event order
http://code.google.com/p/los-cocos/issues/detail?id=163

What steps will reproduce the problem?

1. Create a heirarchy of event-handling layers. At least one of the layers
should have multiple child layers. All layers should handle the same event
and not return EVENT_HANDLED.

Example:

Scene
BackgroundLayer (z=0)
GuiLayer (z=1)
AlphaButton (z=0)
BravoButton (z=1)

2. Run the program and fire the event.

What is the expected output?

I expect the event handlers to be called in the following order:

1) BravoButton
2) AlphaButton
3) GuiLayer
4) BackgroundLayer

What do you see instead?

In reality, the order is like this:

1) BackgroundLayer
2) AlphaButton
3) BravoButton
4) GuiLayer

The problem is that the event handlers are simply pushed onto the window in
order of the layer's children list (which is sorted with the lowest Z
values first). This results in the handlers being called from
back-to-front, instead of the documented front-to-back (from
\cocos\layer\base_layers.py: "Events are propagated to layers (from front
to back) until some layer catches the event and accepts it.").

I need the order to be front-to-back so I can implement a basic GUI, in
which events (like a mouse click) can be first caught by a widget (like a
button) before being optionally passed to the background (i.e. if no button
was clicked).

I have attached a patch file to fix this issue. Basically I just reversed
the order of pushing child handlers onto the window in the scene and
layer's push_all_handlers() method. I also removed event pushing from the
on_enter method, since that would otherwise cause events to be registered
in order of on_enter being called.

Attachments:
event order fix.patch 2.4 KB

[codesite...@google.com]

Updates:
Status: Accepted

Comment #1 on issue 163 by ccanepacc: Event order
http://code.google.com/p/los-cocos/issues/detail?id=163

fwd to the general list,
http://thread.gmane.org/gmane.comp.python.cocos2d.user/1238
will summarize later.