[OpenLayers-Dev] map div has 0 height, width when loading in non-active tab

[Gregers Gram Rygg]

Hi,

Yes, we had a similar issue recently.

The map div needs to be visible when initializing the map (pleas
correct me if I'm wrong), so we fixed it by waiting to initialize the
map until the first time the map tab is activated.

Regards,
Gregers

On Tue, Oct 19, 2010 at 7:12 PM, crb <jcbeaude at yahoo.com> wrote:
>
> Greetings OL-devvers.
>
> We have an issue that's proving hard to fix/workaround and I'm hoping this
> forum can help.  We have a .NET app that has a main page with two tabs, a
> 'Search' tab and a 'Data' tab.  The OL map is in the 'Search' tab.  Whenever
> the page loads in the Data tab, then the map.div height and width are 0 and
> the map fails to initialize and throws an exception, which if uncaught
> causes all subsequent page javascript to fail.  As a test we tried
> explicitly setting the div height and width to fixed pixel values in the
> div's style but we get the same results.
>
> The error occurs when the layer does a loadMapObject() (in this case
> VirtualEarth, but we've also seen it occur in a vector layer) which does the
> following:
>
> var veDiv = OpenLayers.Util.createDiv(this.name);
> var sz = this.map.getSize();         // returns null
> vsDiv.style.width = sz.w + "px";    // throws an exception
>
>
> and is traceable back to this code in the Map.js:
>
> getSize: function () {
>    var size = null;
>    if (this.size != null) {
>        size = this.size.clone();
>    }
>
>    return size;
> }
>
>
> The full call stack beginning with our custom code is:
> this.map.addLayer(layer) -> Map.addLayer() -> layer.setMap(this) ->
> EventPane.setMap() -> this.loadMapObject() -> VirtualEarth.loadMapObject()
> -> map.getSize()
>
> When the map successfully loads (i.e. when the active tab is the Search tab)
> the map.div has the following valid property values (all are based on my
> screen size, obviously, but importantly non-zero):
> clientHeight: 473
> clientWidth: 787
> offsetHeight: 475
> offsetWidth: 789
> get scrollHeight: 473
> scrollWidth: 787
>
> When it fails, it has the following:
> clientHeight: 0
> clientWidth: 0
> offsetHeight: 0
> offsetWidth: 0
> get scrollHeight: 0
> scrollWidth: 0
>
> Unfortunately forcing the page to load on the Search tab every time is not a
> viable option for us.
>
> Has anyone else ever run across anything similar and/or have any thoughts on
> how we might overcome this?
> --
> View this message in context: http://osgeo-org.1803224.n2.nabble.com/map-div-has-0-height-width-when-loading-in-non-active-tab-tp5651744p5651744.html
> Sent from the OpenLayers Dev mailing list archive at Nabble.com.
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