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    <div class="moz-cite-prefix">Sure, I'd be glad to help.  What
      version do you use ?<br>
      <br>
      Alexandre<br>
      <br>
      <br>
      On 13-02-27 12:36 PM, Robert Smart wrote:<br>
    </div>
    <blockquote
      cite="mid:SNT401-EAS1579FC4FA8B4C553CE487E6AAFD0@phx.gbl"
      type="cite">
      <div>Hi, </div>
      <div><br>
      </div>
      <div>Thanks for a really in depth answer. It really explains it
        well.</div>
      <div><br>
      </div>
      <div>Unfortunately my javascript skills are pretty basic at the
        moment, so a lot of that went over my head<span
          class="Apple-style-span" style="-webkit-tap-highlight-color:
          rgba(26, 26, 26, 0.292969); -webkit-composition-fill-color:
          rgba(175, 192, 227, 0.230469);
          -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);">!</span></div>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);"><br>
        </span></div>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);">I like the sound of the vertexselection event on
          the vector layer class. Could you give me a few more hints
          about how this might work?</span></div>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);"><br>
        </span></div>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);">Or even better give me an example bit of code :)</span></div>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);"><br>
        </span></div>
      <span class="Apple-style-span" style="-webkit-tap-highlight-color:
        rgba(26, 26, 26, 0.292969); -webkit-composition-fill-color:
        rgba(175, 192, 227, 0.230469); -webkit-composition-frame-color:
        rgba(77, 128, 180, 0.230469); ">We would need to be able to
        access the vertex index of the selected vertex, and i guess
        there would have to be a method of removing the vertex from the
        feature, which would trigger a redraw of the feature on the map.</span>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);"><br>
        </span></div>
      <div><span class="Apple-style-span"
          style="-webkit-tap-highlight-color: rgba(26, 26, 26,
          0.292969); -webkit-composition-fill-color: rgba(175, 192, 227,
          0.230469); -webkit-composition-frame-color: rgba(77, 128, 180,
          0.230469);">We would have to also be able to define a style
          for that selected vertex too, and i suppose add some error
          trap to ensure that we can't select a virtual vertex?<br>
        </span></div>
      <div>
        <div><span class="Apple-style-span"
            style="-webkit-tap-highlight-color: rgba(26, 26, 26,
            0.292969); -webkit-composition-fill-color: rgba(175, 192,
            227, 0.230469); -webkit-composition-frame-color: rgba(77,
            128, 180, 0.230469);"><br>
          </span></div>
        <div><span class="Apple-style-span"
            style="-webkit-tap-highlight-color: rgba(26, 26, 26,
            0.292969); -webkit-composition-fill-color: rgba(175, 192,
            227, 0.230469); -webkit-composition-frame-color: rgba(77,
            128, 180, 0.230469);">Thanks again,</span></div>
        <div><span class="Apple-style-span"
            style="-webkit-tap-highlight-color: rgba(26, 26, 26,
            0.292969); -webkit-composition-fill-color: rgba(175, 192,
            227, 0.230469); -webkit-composition-frame-color: rgba(77,
            128, 180, 0.230469);"><br>
          </span></div>
        <div><span class="Apple-style-span"
            style="-webkit-tap-highlight-color: rgba(26, 26, 26,
            0.292969); -webkit-composition-fill-color: rgba(175, 192,
            227, 0.230469); -webkit-composition-frame-color: rgba(77,
            128, 180, 0.230469);">Rob</span></div>
        <div><br>
          <br>
        </div>
        <div><br>
          On 27 Feb 2013, at 13:51, "Alexandre Dubé" <<a
            moz-do-not-send="true" href="mailto:adube@mapgears.com">adube@mapgears.com</a>>
          wrote:<br>
          <br>
        </div>
        <blockquote type="cite">
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            <div class="moz-cite-prefix">Hi Rob,<br>
              <br>
                This would indeed be a nice feature to have.  Looking at
              the ModifyFeature control, I think this could be easily
              accomplished with minor modifications.<br>
              <br>
                If we look at the ModifyFeature control, it creates a
              DragFeature control to allow dragging the vertices
              around.  When you "mouse hover" a vertex feature, a
              callback function is triggered because it was defined here
              :<br>
                 
              <a moz-do-not-send="true" class="moz-txt-link-freetext"
href="https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Control/ModifyFeature.js#L267">https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Control/ModifyFeature.js#L267</a><br>
              <br>
                That's the callbacks for the OpenLayers.Handler.Feature
              object the drag control needs to interact with features on
              the map.  The drag control defines its callbacks method in
              the featureCallbacks object :<br>
                 
              <a moz-do-not-send="true" class="moz-txt-link-freetext"
href="https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Control/DragFeature.js#L119">https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Control/DragFeature.js#L119</a><br>
              <br>
                and here's the list of callbacks you can set to a
              feature handler: click, clickout, over, out, and dblclick.<br>
                 
              <a moz-do-not-send="true" class="moz-txt-link-freetext"
href="https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Handler/Feature.js#L30">https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Handler/Feature.js#L30</a><br>
              <br>
                So, back in the ModifyFeature control, you could add a
              'click' callback function just next to the 'over' one. 
              Instead of coding what you want it to do directly in the
              source, just define an abstract function that needs to be
              overriden OR you could fire an new vector layer event :
              vertexselected (which would need to be added to
              OpenLayer.Layer.Vector).<br>
              <br>
                Whoa, sorry for the long reply :)   In short, try to
              create a delegate method or event we could register to to
              do whatever we wanted on vertex selection.<br>
              <br>
                Does that make sense ?<br>
              <br>
              HTH,<br>
              <br>
              Alexandre<br>
              <br>
              <br>
              On 13-02-26 11:42 AM, Robert Smart wrote:<br>
            </div>
            <blockquote
              cite="mid:SNT127-DS253CEE7303DEA8D2C4CA9AAFC0@phx.gbl"
              type="cite">
              <div dir="ltr">
                <div style="FONT-FAMILY: 'Calibri'; COLOR: #000000;
                  FONT-SIZE: 12pt"><font face="Times New Roman">Hi All,<br>
                    <br>
                    I'm trying to port some existing functionality into
                    open layers and have <br>
                    managed to get most of it working. I'm just stuck on
                    a seemingly simple <br>
                    task.<br>
                    <br>
                    The current code allows a user to highlight a
                    polygon vertex by clicking on <br>
                    it (which changes its colour), so that the user can
                    then press a delete <br>
                    button to remove the vertex.<br>
                    <br>
                    Using the modify control I'm able to display the
                    vertices, and even delete <br>
                    them if I click on it and then press 'del' on my
                    keyboard, but this is not a <br>
                    great solution as there is no visual clue as to what
                    vertex has been <br>
                    selected.<br>
                    <br>
                    So is there a way to highlight or change the colour
                    of a single vertex the <br>
                    user has clicked on? is there then a way to remove
                    that vertex via code and <br>
                    have the polygon redraw on the screen to suit?<br>
                    <br>
                    I think this would actually be quite useful as a
                    standard feature as there <br>
                    are many cases where one might want to select an
                    individual vertex.<br>
                    <br>
                    Thanks,<br>
                    <br>
                    Rob</font> </div>
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</pre>
            </blockquote>
            <br>
            <br>
            <pre class="moz-signature" cols="72">-- 
Alexandre Dubé
Mapgears
<a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="http://www.mapgears.com">www.mapgears.com</a>
</pre>
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        </blockquote>
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          <div><span>_______________________________________________</span><br>
            <span>Users mailing list</span><br>
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                href="mailto:Users@lists.osgeo.org">Users@lists.osgeo.org</a></span><br>
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        </blockquote>
      </div>
    </blockquote>
    <br>
    <br>
    <pre class="moz-signature" cols="72">-- 
Alexandre Dubé
Mapgears
<a class="moz-txt-link-abbreviated" href="http://www.mapgears.com">www.mapgears.com</a>
</pre>
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