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<P><FONT SIZE=2 FACE="Arial">I have a problem that I don't know how to solve … I've poked around in the OL code, and I can't figure out how to do what I want. Can anyone here recommend a course of action?</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I am working on developing a tracking application which shows the tracks of multiple individuals on a single map. The track for a single individual consists of a set of positions shown by various icons connected in order by a line. Each position may need to be shown using a different icon, depending upon some other data collected while reading the location.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">In my current implementation, I have the markers in one layer and the line connecting the markers in another layer, which works great and gives me exactly the visual presentation I want. However, since there are two layers, there are two separate check boxes in the Layer Switcher control. This is confusing for the user, since logically it makes the most sense to have one layer (and consequently one checkbox) associated with one individual.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">The only way I could think of to merge the two layers together would be to draw polygons in the line layer instead of placing icons/markers in a separate marker layer.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">What I would REALLY like is some way to merge both markers and vectors together into a single layer, so that when I select/deselect that layer in the Layer Switcher, both markers and vectors appear/disappear concurrently. But I realize that due to the architecture of OL, it might not be possible to do that.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Alternately, I could achieve the result I want if the following additions were made to the layer code:</FONT>
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<P><FONT SIZE=2 FACE="Arial">1. Have a property associated with a layer that causes it to appear in the Layer Switcher list. This could be set as an option while constructing a new Layer object, and the Layer Switcher could pay attention to this property when generating the layer form.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">2. When a layer is selected or deselected in the Layer Switcher, trigger a "showlayer" or "hidelayer" event. That way, when the marker layer is shown/hidden, the showlayer/hidelayer event handler for the marker layer could cause the corresponding line layer to be shown/hidden.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">So, is there some way to achieve this in OL 2.4? Or should I go start modifying the code myself?</FONT>
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<P><FONT SIZE=2 FACE="Arial">Thanks!</FONT>
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<P><FONT SIZE=2 FACE="Arial">-eP</FONT>
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