I have a map that changes tiles based on four radio buttons. I need the popup window that appears when you roll over a tile to change as the different map layers change. I've gotten it to appear but when I switch layers the map just adds another popup window. I tried using control.removeFrom(map) but it doesn't seem to work. I think my logic may be screwed up somewhere. Here is one of the if statements:

if (two == true && black == true) { 
                function blkNineStyle(feature) {
                    return {
                    fillColor: getColor(feature.properties.pctBlack9000),
                    weight: 2,
                    opacity: 1,
                    color: '#666',
                    dashArray: '2',
                    fillOpacity: 0.9
                    };
                }
                                    //Tried to us this to take off the control.
                info.removeFrom(map);
                map.removeLayer(geojson);
                geojson = L.geoJson(tracts, {style: blkNineStyle, onEachFeature: onEachFeature}).addTo(map);

                var info = L.control();

                info.onAdd = function (map) {
                    this._div = L.DomUtil.create('div', 'info');
                    this.update();
                    return this._div;
                };

                info.update = function (props) {
                    this._div.innerHTML = '<h4>Percent White population change</h4>' + (props ? '<b>' + props.name + '</b><br />' + props.pctBlack9000 + '%' : 'Hover over a tract');
                };

                info.addTo(map);
            }

You can see the (broken) map here.

I have a map that changes tiles based on four radio buttons. I need the popup window that appears when you roll over a tile to change as the different map layers change. I've gotten it to appear but when I switch layers the map just adds another popup window. I tried using control.removeFrom(map) but it doesn't seem to work. I think my logic may be screwed up somewhere. Here is one of the if statements:

if (two == true && black == true) { 
                function blkNineStyle(feature) {
                    return {
                    fillColor: getColor(feature.properties.pctBlack9000),
                    weight: 2,
                    opacity: 1,
                    color: '#666',
                    dashArray: '2',
                    fillOpacity: 0.9
                    };
                }
                                    //Tried to us this to take off the control.
                info.removeFrom(map);
                map.removeLayer(geojson);
                geojson = L.geoJson(tracts, {style: blkNineStyle, onEachFeature: onEachFeature}).addTo(map);

                var info = L.control();

                info.onAdd = function (map) {
                    this._div = L.DomUtil.create('div', 'info');
                    this.update();
                    return this._div;
                };

                info.update = function (props) {
                    this._div.innerHTML = '<h4>Percent White population change</h4>' + (props ? '<b>' + props.name + '</b><br />' + props.pctBlack9000 + '%' : 'Hover over a tract');
                };

                info.addTo(map);
            }

You can see the (broken) map here.

• javascript
• jquery
• leaflet

3 Answers 3

I had this same problem myself and I just solved it.

I had to define an empty variable in the global environment (outside any functions you're using). This isn't a full script or anything, but the general idea I'm describing is below:

    var info;  // CREATING INFO VARIABLE IN GLOBAL ENVIRONMENT
    function makeMap() {
    ..... geojsons, styles, other stuff ....

    // REMOVING PREVIOUS INFO BOX
    if (info != undefined) {
    info.removeFrom(map)
    }

    // making current layer's info box
    info = L.control();

    info.onAdd = function (map) {
    this._div = L.DomUtil.create('div', 'info');
    this.update();
    return this._div;
    };

    info.update = function (props) {
    this._div.innerHTML = '<h4>Data by Zip Code</h4>' + (props ?
    '<b>Zip Code:  ' + props.id + '</b><br />Value:  ' + matchKey(props.id, meanById)
    : 'Hover over a zip code');
    };

    info.addTo(map);

    ..... other stuff again ......

    } // end function

I am very new to both Leaflet and javascript, so I have to say that I'm not exactly sure where to place the info.removeFrom(map) line in the code you have posted at the map link you provided, but you are on the right track with 'info.removeFrom(map)' .

I was able to problem-solve my issue with dynamic legends and info boxes by fiddling around here: http://jsfiddle/opensas/TnX96/

I believe you want to remove the control similarly how you added it.

In this case leaflet provides direct remove() method similar to addTo(map) method.

Example-

Whenever you want to remove the legend control use following code-

Create Control-

var legendControl = L.control({position: 'bottomleft'});
    legendControl.addTo(mymap);

Remove Control-

legendControl.remove();

For more details refer/click here...

Despite the fact that this question was asked a year ago, I recently had to e up with a solution to a similar problem myself so feel as if I should share in case anybody else ends up here like I did.

The L.control() object in Leaflet isn't technically a layer, and this is why trying to add and remove it some times doesn't work in the same way as for layers.

http://leafletjs./reference.html#icontrol

As the L.control constructor requires you only to "create all the neccessary DOM elements for the control", the HTML content of the div itself can be updated and deleted as and when required. Thus, to make a control feature appear and disappear from the map, and instead of adding and removing the L.control object, just adjust the HTML contents of the div contained by it. An empty div would result in no control feature being shown by the map.

Thus the above snippet would bee:

//construct control, initialize div

info = L.control();
info.onAdd = function (map) {
this._div = L.DomUtil.create('div', 'info');
this.update();
return this._div;
};
if (two == true && black == true) { 
            function blkNineStyle(feature) {
                return {
                fillColor: getColor(feature.properties.pctBlack9000),
                weight: 2,
                opacity: 1,
                color: '#666',
                dashArray: '2',
                fillOpacity: 0.9
                };
            }

//set div content to empty string; makes control disappear from map

            info.getContainer().innerHTML='';

            map.removeLayer(geojson);
            geojson = L.geoJson(tracts, {style: blkNineStyle, onEachFeature: onEachFeature}).addTo(map);

//update content of control to make the control reappear

            info.update = function (props) {
                this._div.innerHTML = '<h4>Percent White population change</h4>' + (props ? '<b>' + props.name + '</b><br />' + props.pctBlack9000 + '%' : 'Hover over a tract');
            };

        }

 //other cases...
if (two == false && black == true) { 

//delete and update control where necessary

    info.getContainer().innerHTML='';