Openlayers creating RegularPolygon that is too small then return false

Question

My project has to use imagelayer to show map , it can create box on map, box will be a area to put device marker on top , but when the box is too small , there will be a bug in project..., so is there some one who can tell me how to prevent this from happening?

The code is below:

// map init
$map = new OpenLayers.Map("gmap");
$map.addControl(new OpenLayers.Control.MousePosition());

//add basic layer
$map.addLayers([new OpenLayers.Layer.Image(
    'Main Layer',
    'images/ec/area/area1.jpg',
    new OpenLayers.Bounds(0, 0, 2565, 1293),
    new OpenLayers.Size(1282.5, 646.5),
    {layers: 'basic'}
)]);

//add vector Layer to map
vectorLayer = new OpenLayers.Layer.Vector("Overlay");//Area layer
vectorLayer1 = new OpenLayers.Layer.Vector("Overlay1");//device layer
$map.addLayers([vectorLayer,vectorLayer1]);

selectControl = {
    selector: new OpenLayers.Control.SelectFeature([vectorLayer,vectorLayer1], {
        onSelect: createPopup,
        onUnselect: destroyPopup
    }),
    box : new OpenLayers.Control.DrawFeature(vectorLayer,
        OpenLayers.Handler.RegularPolygon, {
            handlerOptions: {
                sides: 4,
                irregular: true
            },
            callbacks: {
                up: function(geometry){

                    if( geometry.getArea() < 2500 ){
                        alert("Box too small can not be create!");
                        return false; //still can not return false!!!!
                    }
                }
            }
        }
    )
};

//this can log Area Size But can not return false!!
selectControl["box"].handler.callbacks.create = function(data) {
    if(data.getArea() < 2500){
        console.log("Area Size:"+data.getArea());
        return false;
    }
}

---

Should I check when the box too small then remove it?

Or how to prevent the create box when the box is too small?

Answer 1

My friend Chris help me to resolve the problem and the answer will be like this: http://jsfiddle.net/v18kuxgf/

polygonLayer.events.register('featureadded', null, function(event) {
                        var feature = event.feature,
                            geometry = feature.geometry;
                        if (geometry.getArea() < 2500) {
                            alert('Box too small to create!');
                            polygonLayer.removeFeatures(feature);
                        }
                    });