On Mar 7, 2011, at 7:39 PM, Eric Lemoine wrote:

> On Monday, March 7, 2011, Leigh Holcombe <[email protected]> wrote:
>> Greetings,
>> 
>> I have a layer constructed from a GeoJSON file, using the following code:
>> var trail1 = new OpenLayers.Layer.Vector("Kaau Crater", {strategies: [new 
>> OpenLayers.Strategy.Fixed()], protocol: new OpenLayers.Protocol.HTTP({url: 
>> "kaaucrater-rb.json", format: new OpenLayers.Format.GeoJSON()}), styleMap: 
>> styles, projection: utm4n});
>> 
>> What I'd like to do is get the bounds or centerpoint of the GeoJSON file 
>> automatically, perhaps by using something like getBounds or getCenterLonLat, 
>> but my newb mind is discovering that I can't perform these operations on the 
>> layer object I have created.  I suspect I need to also create a geometry 
>> layer from the GeoJSON file, but I am not sure how to do that.  Can anyone 
>> provide any direction?
> 
> Hi. The Vector layer has a getDataExtent method, that you can call
> when the features have been added to the layer:
> 
> trail1.events.on({"loadend": function() {
>    var bounds = trail1.getDataExtent();
> }});
> 
> -- 
> Eric Lemoine
> 

Thank you, that works very well.  However, it's a little too late in the 
process.  My plan is to use the bounds/extent to calculate the center of the 
overlay, and then pass that to map.setCenter.  Is there a way to make this 
happen before the loadend?

Additionally, where can I find a complete list of the standard events, such as 
loadstart and loadend?

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