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<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>Hi,</FONT></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>perhaps these
three examples may be helpful.</FONT></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>In the first and
the second example I use a LayerSwitcher, <BR>where the user can choose the
layers of an OpenLayers.Layer.WMS for display.</FONT></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>The third example
shows the use of SLD to color a layer for different attributes.</FONT></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2
face=Arial>[1]:http://gis.ibbeck.de/ginfo/apps/OLExamples/OL27/examples/GroundOverlay/GroundOverlay.asp<BR>[2]:http://gis.ibbeck.de/OLClient/OLClient.asp?WMC=data/WMC/!World.wmc.xml</FONT></DIV>
<DIV> </DIV>
<DIV dir=ltr align=left><FONT color=#0000ff size=2
face=Arial>[3]:http://gis.ibbeck.de/ginfo/apps/OLExamples/OL210/MapServer_SLD_World/MapServer_SLD_World.asp<BR></FONT></DIV>
<DIV dir=ltr align=left><SPAN class=062141017-21092014><FONT color=#0000ff
size=2 face=Arial>Regards,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=062141017-21092014><FONT color=#0000ff
size=2 face=Arial>Arnd</FONT></SPAN></DIV><BR>
<DIV dir=ltr lang=de class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>Von:</B> openlayers-users-bounces@lists.osgeo.org
[mailto:openlayers-users-bounces@lists.osgeo.org] <B>Im Auftrag von </B>Andreas
Forø Tollefsen<BR><B>Gesendet:</B> Freitag, 19. September 2014
20:02<BR><B>An:</B> Mark Prins<BR><B>Cc:</B> openlayers-users<BR><B>Betreff:</B>
Re: [OpenLayers-Users] Too many layers?<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV dir=ltr>Thanks for all your input. Really, this seems to be an issue with
how we can use OpenLayers to visualize a number of variables from the same
layer.
<DIV>In fact, my data is all from just two shapefiles representing two different
administrative units, with many variables for each layer. </DIV>
<DIV>This should basically only require me to have two layers in the map. One
for each administrative level.</DIV>
<DIV><BR></DIV>
<DIV>What I would like to have is just a simple "variable selector" for each of
the layer, where the user can select the variable in each of the layers that
should be symbolized, where each variable has a predefined SLD style. However, I
have not seen an example showing this, or seen code examples. </DIV>
<DIV><BR></DIV>
<DIV>Is this possible in Openlayers without too much custom coding? It seems to
me sometimes that Openlayers is not always easy to use to create thematic
maps.</DIV>
<DIV><BR></DIV>
<DIV>My solution to reduce the load is to have a custom LayerSwitcher, where
only one layer can be shown as overlay at the time.</DIV>
<DIV><BR></DIV>
<DIV>Andreas</DIV>
<DIV><BR></DIV></DIV>
<DIV class=gmail_extra><BR>
<DIV class=gmail_quote>2014-09-19 15:51 GMT+02:00 Mark Prins <SPAN
dir=ltr><<A href="mailto:mc.prins@gmail.com"
target=_blank>mc.prins@gmail.com</A>></SPAN>:<BR>
<BLOCKQUOTE
style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex"
class=gmail_quote>in this specific case I think you should really (re)think
your user<BR>interaction design. Think about:<BR>- Do you really want a user
to be able to switch on all these layers<BR>at the same time?<BR>- Does the
map still make sense if there are more than 3 layers<BR>selected (especially
if they overlap)?<BR>- Is there any way to reduce the options by combining
several areas<BR>into one layer?<BR><BR>We came up with a megamenu structure
(basically a list selector) for<BR>mapping a few hundred statistical units in
our project<BR>see: <A
href="https://github.com/MinELenI/CBSviewer/blob/master/src/main/webapp/WEB-INF/jsp/main_menu_theme_include.jsp"
target=_blank>https://github.com/MinELenI/CBSviewer/blob/master/src/main/webapp/WEB-INF/jsp/main_menu_theme_include.jsp</A><BR>
<DIV class=HOEnZb>
<DIV class=h5><BR><BR>2014-09-18 7:51 GMT+02:00 Andreas Forø Tollefsen <<A
href="mailto:andreasft@gmail.com">andreasft@gmail.com</A>>:<BR>>
Hi,<BR>><BR>> I am working on a thematic mapping platform showing data
at local<BR>> administrative levels.<BR>> I have many layers, so I run
into problems (see screenshot:<BR>> <A
href="http://gisintersect.com/many_layers.png"
target=_blank>http://gisintersect.com/many_layers.png</A>).<BR>><BR>> Is
there any way I can collapse groups of layers within the layer
switcher?<BR>> I have a high number of layers, as you can see in the
switcher. Hence, I<BR>> need some way to collapse/group/categorize the
layers, so that I do not need<BR>> to show all of them in the layerswitcher
at once.<BR>> The result is that layers drop outside the map, so either,
there is a<BR>> maximum number of layers, or there should be a better way
to do it.<BR>><BR>> Andreas<BR>><BR></DIV></DIV><SPAN
class="im HOEnZb">> _______________________________________________<BR>>
Users mailing list<BR>> <A
href="mailto:Users@lists.osgeo.org">Users@lists.osgeo.org</A><BR>> <A
href="http://lists.osgeo.org/mailman/listinfo/openlayers-users"
target=_blank>http://lists.osgeo.org/mailman/listinfo/openlayers-users</A><BR><BR><BR><BR></SPAN><SPAN
class=HOEnZb><FONT color=#888888>--<BR>Disclaimer;<BR>This message is just a
reflection of what I thought at the time of<BR>sending. The message may
contain information that is not intended for<BR>you or that you don't
understand.<BR></FONT></SPAN>
<DIV class=HOEnZb>
<DIV class=h5>_______________________________________________<BR>Users mailing
list<BR><A href="mailto:Users@lists.osgeo.org">Users@lists.osgeo.org</A><BR><A
href="http://lists.osgeo.org/mailman/listinfo/openlayers-users"
target=_blank>http://lists.osgeo.org/mailman/listinfo/openlayers-users</A></DIV></DIV></BLOCKQUOTE></DIV><BR></DIV>
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