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vectoropenlayerslimitlayer

OpenLayers Vector Layer Maximum number of features

I was wondering if it is possible to limit the number of features you an draw on a vectorylayer. If I already have a polygon drawn, and go to draw another it will delete the first feature.

If not is it possible to add a listener to the vector layer, so that I can erase all features when clicking to draw?

Thanks!!!

Solution

  • You can't set max number of features on Vector Layer, but it has a whole lot of events where you can inject your own logic. Here are available events:

    "beforefeatureadded", "beforefeaturesadded",
"featureadded", "featuresadded", "beforefeatureremoved",
"beforefeaturesremoved", "featureremoved", "featuresremoved",
"beforefeatureselected", "featureselected", "featureunselected", 
"beforefeaturemodified", "featuremodified", "afterfeaturemodified",
"vertexmodified", "vertexremoved", "sketchstarted",
"sketchmodified", "sketchcomplete", "refresh"

    You can use "beforefeatureadded" for instance:

    your_vectror_layer.events.on({'beforefeatureadded': function(){
  //Remove first feature or whatever you want to do
}});