[OpenLayers-Users] Displaying attributes by onmouseover

[Alexandre Dube]

Hi Kai,

  I've accomplished this kind of feature by customizing my own control.  
Its main purpose is to "highlight" features, but there's already a 
"displayPopup" property set to true by default.  You could customize the 
content of the popup to do what you want it to do and that should do the 
trick.

  See an example and the code :

http://dev.openlayers.org/sandbox/adube/openlayers/examples/highlight-feature.html
http://svn.openlayers.org/sandbox/adube/openlayers/lib/OpenLayers/Control/HighlightFeature.js

  Or, you could use displayPopup:false and register your own featureset 
event, like in this example which displays Ext.Windows instead of a OL 
popup : ( click on the "edit road" button )

http://dev4.mapgears.com/bdga-mapfish/bdgaWFS-T.html

  Hope this helps,

Alexandre

Kai Behncke wrote:
> Hi Till,
>
>
> thank you for the code :-)
> It`s quite helpful,although I didn`t get it to run as I want so far.
>
> The wfs is correctly visualized, I use that one:
> http://www.gastronomap.de/cgi-bin/mapserv?map=/home/promotion/behncke/gastronomap_wms/gastronomap_wfs.map&SERVICE=WFS&VERSION=1.0.0&Request=GetFeature&Typename=gastronomie_wfs
>
> If I do a mouseover at the different points of the wfs the following
>
> feature_info_hover(arguments[0], gastronomap_wfs) is called.
>
>
> I try:
>
> function feature_info_hover(feature, myWfsLayer)
> {
> alert (myWfsLayer.getFeatureById(feature.gid));
>
>
> ...and get always an alert with "null".
>
> (an "alert (feature);" gives an alert with [object Object], so I think the arguments[0]-parameter is transported correctly).
>
> Has anybody an idea why the gid of the feature doesn`t appear in the alert?
>
> Best regards, Kai
> -------- Original-Nachricht --------
>   
>> Datum: Tue, 24 Feb 2009 15:20:45 +0100
>> Von: Till Adams <adams at terrestris.de>
>> An: Kai Behncke <Kai-Behncke at gmx.de>, users at openlayers.org
>> Betreff: Re: [OpenLayers-Users] Displaying attributes by onmouseover
>>     
>
>   
>> Kai Behncke schrieb:
>>     
>>> Dear Openlayers-Users,
>>>
>>>
>>> I use an application with a couple of point objects (500) visualized by
>>>       
>> a wms in the map.
>>     
>>> I´m looking for a function that pops up a small window (for example
>>>       
>> with the name of an object) if I do a mouseover at an object in the map.
>>     
>>> I think for this using a second layer ("invisible" wfs) could be best
>>>       
>> practise (or which other possibilities shall be usable)??
>>     
>>> As far as I can see a script like that does not exist in the examples
>>>       
>> (if I haven`t overseen it.....).
>>     
>>> I would like to try to write one and supply it.
>>> What is the way if I want to supply a script like that to the examples?
>>>
>>> Best regards, Kai Behncke
>>>   
>>>       
>> Kai,
>>
>>
>> we use WFS and the select feature from OL::
>>
>> **
>>  * -------------------------------------------------------------------
>>  * feature_info_hover
>>  * function to hover a feature open a new pop up window and destroy
>>  * it after 3000 milliseconds (variable at end of function)
>>  *
>>  * @feature
>>  * -------------------------------------------------------------------
>>  */
>> function feature_info_hover(feature, myWfsLayer)
>> {
>>     if (this.popup && NABU.MAP && NABU.MAP.popups && 
>> NABU.MAP.popups.length > 0)
>>     {
>>         window.clearTimeout(this.autodestroy);
>>         this.popup.destroy();
>>         this.popup = null;
>>     }
>>     var myFeature = myWfsLayer.getFeatureById(feature.id);
>>    
>>     if (myFeature)
>>     {
>>    
>>         var window_position = new 
>> OpenLayers.LonLat(myFeature.geometry.x, myFeature.geometry.y);
>>         this.popup = new OpenLayers.Popup("ol-info-popup", 
>> window_position, null, '<div class="map-kurzinfo-popup"><span>' + 
>> myFeature.data.name + '</span><br><span onclick="javascript:OpenInfo(\'' 
>> + myFeature.data.gid + '\',\'' + myWfsLayer.typename + '\')" 
>> style="cursor:pointer;">weitere Informationen</span></div>', false);
>>         this.popup.autoSize = true;
>>         map.addPopup(this.popup, true);
>>         this.autodestroy = window.setTimeout(function()
>>         {
>>             if (map && map.popups && map.popups.length > 0)
>>             {
>>                 var len = map.popups.length;
>>                 for (var i = 0; i < len; i++)
>>                 {
>>                     if (map.popups[i] && map.popups[i].destroy)
>>                     {
>>                         map.popups[i].destroy();
>>                     }
>>                 }
>>             }
>>         }, 3000);
>>     }
>> }
>>
>> See that we refer manually to "myFeature.data.gid", 
>> "myFeature.data.name" and "myFeature.data.typename" which is not really 
>> them ost elegant way...
>>
>> Then initiate it through that code in the ol init function:
>>
>>
>>     hover.parken = new OpenLayers.Control.SelectFeature(tbl_p_parken, {
>>         callbacks: {
>>             'over': function()
>>             {
>>                 feature_info_hover(arguments[0], tbl_p_parken);
>>             }
>>         }
>>     });
>>     map.addControl(hover.parken);
>>     hover.parken.activate();
>>
>>
>> Where "tbl_p_parken" is our WFS defined in the layer section of the ol 
>> init function. This only works for one layer as the select feature of OL 
>> in the moment only handles one layer, this is to be changed on the next 
>> OL versions.
>>
>> Regards, Till
>>
>>
>> ----------------------------------------------------------
>> terrestris GmbH & Co. KG
>> Irmintrudisstrasse 17
>> 53111 Bonn
>> Germany
>>
>> Till Adams
>> Geschäftsführung
>>
>> Tel: +49 (0)228 / 962 899-52
>> Fax: +49 (0)228 / 962 899-57
>> adams at terrestris.de http://www.terrestris.de
>> Amtsgericht Bonn, HRA 6835
>> ---------------------------------------------------------
>>
>> Komplementärin:
>>
>> terrestris Verwaltungs GmbH
>>
>> vertreten durch:
>> Hinrich Paulsen, Till Adams
>>     
>
>   


-- 
Alexandre Dubé
Mapgears
www.mapgears.com