vector layers: loadstart event eventually triggered without loadend

[fvanderbiest]

I was playing with the loadingPanel Addin Control, and I found out that a vector layer with a BBOX strategy was the culprit for not minimizing the control when I zoom in quickly so that several zoom levels are passed at once.

What happens in this case? The strategy's triggerRead method is called several times in a short while. This method first aborts the protocol, and then triggers the "loadstart" event. This means that loadstart events are triggered without their loadend counterparts. Hence the always maximized control.

To fix this, I suggest adding an "abort" event to the protocol (which does not have any event for now - cf  http://trac.openlayers.org/ticket/1767). The loadingPanel control would listen to this event for vector layers and call the decreaseCounter method.

[fvanderbiest]

Eric suggests to trigger the loadend event when calling protocol.abort(). Tests pass with FF3.

[bartvde]

Francois, do you see a problem in triggering loadend on abort? If so, could that be a solution instead of introducing another event?

[bartvde]

Ok, Eric had the same suggestion as what I was thinking.

[bartvde]

(In [10100]) bbox strategy should call loadend when aborting, p=fvanderbiest, r=me (closes #2504)