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I'm trying to display the coordinates of a Feature or vector layer after I use the modify radio button to resize my vector, but it does not work, nor on my drag feature. I'm using afterFeatureModified(), maybe this is wrong?

It only works with my onFeatureAdded() when I finish drawing a circle.

Below is my code, Any assistance is much appreciated.

      <html xmlns="http://www.w3.org/1999/xhtml">
      <head>
      <!--CSS for Map -->
      <style type="text/css">
     html, body, #map {
         margin: 0;
         width: 100%;
         height: 100%;
        }
      </style>
      <!-- END of CSS for Map -->

      <!--CSS for Controls to draw circle and navigate -->
      <style type="text/css">
    #controls {
        position: absolute;
        bottom: 1em;
        left: 100px;
        width: 400px;
        z-index: 20000;
        padding: 0 0.5em 0.5em 0.5em;
    }

    #controlToggle {
        padding-left: 1em;
    }

    #controlToggle li {
        list-style: none;
    }

    #form {
        position: absolute;
        bottom: 1em;
        left: 400px;
        width: 200px;
        z-index: 20000;
        padding: 0 0.5em 0.5em 0.5em;
    }
    </style>
    <!-- END CSS for Controls to draw circle -->

    <link href="css/style.css" rel="stylesheet" type="text/css" />
    <script src="js/firebug.js"></script>
    <script src="http://openlayers.org/dev/OpenLayers.js"></script>

    <script type="text/javascript">
      var lon = 24.0000000000;
      var lat = -29.000000000000;

      var zoom = 4;
      var map, layer, vectors, controls;

      function init() {




      // Because the Streetmaps system uses 300x300 tiles, we need to set up the scaling variables to work with these
      var aRes = [90, 45, 22.500000, 11.250000, 5.625000, 2.812500, 1.406250, 0.703125, 0.351563, 0.175781, 0.087891, 0.043945, 0.021973, 0.010986, 0.005493, 0.002747, 0.001373, 0.000687, 0.000343];
      for (var l = 0; l < aRes.length; l++) { aRes[l] = aRes[l] / 300; }

      // Normal init, but we pass through the info about the zoom/scaling as options
      map = new OpenLayers.Map('map', { tileSize: new OpenLayers.Size(300, 300), projection: 'CRS:84', numZoomLevels: aRes.length, resolutions: aRes, maxResolution: 360 / 300 });

      // At this point the control is used as per normal            
      layer1 = new OpenLayers.Layer.WMS(
                      'Streetmaps Streets',
                      'http://www.streetmaps.co.za/WMS/?',
                      {
                          key: 'HZPGNWPNDYPREPTIKSIHWKYKQYYOQVYX',
                          service: 'WMS',
                          request: 'GetMap',
                          version: '1.3.0',
                          layers: 'sm.maps.tiled',
                          format: 'image/png'
                      }
            );

      layer2 = new OpenLayers.Layer.WMS(
                      'Streetmaps Imagery',
                      'http://www.streetmaps.co.za/WMS/?',
                      {
                          key: 'HZPGNWPNDYPREPTIKSIHWKYKQYYOQVYX',
                          service: 'WMS',
                          request: 'GetMap',
                          version: '1.3.0',
                          layers: 'sm.imagery',
                          format: 'image/png'
                      }
            );

      // This loads the map
      map.addLayer(layer1);
      map.addLayer(layer2);

      map.setCenter(new OpenLayers.LonLat(lon, lat), zoom);
      map.addControl(new OpenLayers.Control.LayerSwitcher());
      var vectors = new OpenLayers.Layer.Vector("vector", { isBaseLayer: true });
      map.addLayers([vectors]);



      // This loads the overlays
      var wms = new OpenLayers.Layer.WMS("OpenLayers WMS",
        "http://vmap0.tiles.osgeo.org/wms/vmap0?", { layers: 'basic' });
      OpenLayers.Feature.Vector.style['default']['strokeWidth'] = '2';

      // allow testing of specific renderers via "?renderer=Canvas", etc
      var renderer = OpenLayers.Util.getParameters(window.location.href).renderer;
      renderer = (renderer) ? [renderer] : OpenLayers.Layer.Vector.prototype.renderers;

      vectors = new OpenLayers.Layer.Vector("Vector Layer", {
          renderers: renderer
      });

      map.addLayers([wms, vectors]);
      map.addControl(new OpenLayers.Control.LayerSwitcher());
      map.addControl(new OpenLayers.Control.MousePosition());
      map.setCenter(new OpenLayers.LonLat(lon, lat), zoom);



      // Now we call an alert to get the bounds or coordinates from a circle or vector we have drawn 
      vectors.events.on({
          featuresadded: onFeaturesAdded
      });

      function onFeaturesAdded(event) {
          var bounds = event.features[0].geometry.getBounds();
          var answer = "bottom: " + bounds.bottom + "\n";
          answer += "left: " + bounds.left + "\n";
          answer += "right: " + bounds.right + "\n";
          answer += "top: " + bounds.top + "\n";
          alert(answer);
      }

      vectors.events.on({
          afterfeaturemodified: afterFeatureModified
      });

      function afterFeatureModified(event) {
          var bounds = event.features[0].geometry.getBounds();
          var answer = "bottom: " + bounds.bottom + "\n";
          answer += "left: " + bounds.left + "\n";
          answer += "right: " + bounds.right + "\n";
          answer += "top: " + bounds.top + "\n";
          alert(answer);
      }


      controls = {
          regular: new OpenLayers.Control.DrawFeature(vectors,
                    OpenLayers.Handler.RegularPolygon,
                    { handlerOptions: { sides: 40} }),
          modify: new OpenLayers.Control.ModifyFeature(vectors)
      };

      for (var key in controls) {
          map.addControl(controls[key]);
      }

      map.setCenter(new OpenLayers.LonLat(0, 0), 3);
      document.getElementById('noneToggle').checked = true;
  }


      function update() {
      // reset modification mode
      //controls.modify.mode = OpenLayers.Control.ModifyFeature.RESHAPE;
      controls["modify"].activate();
      controls.modify.mode = OpenLayers.Control.ModifyFeature.ROTATE;

      var resize = document.getElementById("resize").checked;
      if (resize) {
          controls.modify.mode |= OpenLayers.Control.ModifyFeature.RESIZE;
          var keepAspectRatio = document.getElementById("keepAspectRatio").checked;
          if (keepAspectRatio) {
              controls.modify.mode &= ~OpenLayers.Control.ModifyFeature.RESHAPE;
          }
      }
      var drag = document.getElementById("drag").checked;
      if (drag) {
          controls.modify.mode |= OpenLayers.Control.ModifyFeature.DRAG;
      }

      //          if (rotate || drag) {
      //              controls.modify.mode &= ~OpenLayers.Control.ModifyFeature.RESHAPE;
      //          }
      //          var sides = parseInt(document.getElementById("sides").value);
      //          sides = Math.max(3, isNaN(sides) ? 0 : sides);
      //          controls.regular.handler.sides = sides;
      //          var irregular = document.getElementById("irregular").checked;
      //          controls.regular.handler.irregular = irregular;
  }


  function toggleControl(element) {
      for (key in controls) {
          var control = controls[key];
          if (element.value == key && element.checked) {
              control.activate();
          } else {
              control.deactivate();
          }
      }
  }
  </script>
  </head>
  <body onLoad="init()">
  <div id="map" class="smallmap"></div>
  <div id="controls">
  <ul id="controlToggle">
    <li>
        <input type="radio" name="type" value="none" id="noneToggle"
               onclick="toggleControl(this);" checked="checked" />

        <label for="noneToggle">navigate</label>
    </li>
    <li>
        <input type="radio" name="type" value="regular" id="regularToggle" onClick="toggleControl(this);" />
        <label for="regularToggle">draw regular polygon</label>
</li>
    <li>
        <input type="radio" name="type" value="modify" id="modifyToggle"
               onclick="update();" />

        <label for="modifyToggle">modify feature</label>
        <ul>
            <li>
                <input id="rotate" type="hidden" 
                       name="rotate" onChange="update()"  checked="checked"/>
            </li>
            <li>
                <input id="resize" type="hidden"
                       name="resize" onChange="update()"  checked="checked"/>
              <input id="keepAspectRatio" type="hidden"
                       name="keepAspectRatio" onChange="update()" checked="checked" />
                <label for="keepAspectRatio"></label>
            </li>
            <li>
                <input id="drag" type="hidden"
                       name="drag" onChange="update()"  checked="checked"/>
            </li>

        </ul>
    </li>
</ul>

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1 Answer 1

up vote 1 down vote accepted

It works, though you need to click back on the "draw regular polygon" radio so that it triggers the afterfeaturemodified. Or you could just use the featuremodified event so that as soon as you finish dragging or resizing it will trigger your function.

Also you'll need to change the var bounds = event.features[0].geometry.getBounds(); for var bounds = event.feature.geometry.getBounds(); because the event only returns one feature as appose to an array of features.

So i think this is what you're looking for:

vectors.events.on({
    featuremodified: featureModified
});

function featureModified(event) {

    var bounds = event.feature.geometry.getBounds();
    var answer = "bottom: " + bounds.bottom + "\n";
    answer += "left: " + bounds.left + "\n";
    answer += "right: " + bounds.right + "\n";
    answer += "top: " + bounds.top + "\n";
    alert(answer);
}
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