leafletjs : Highlight polyline on mouseover - leaflet

Seems the title is quite self-explanatory but to elaborate more, here is what I'm having trouble with, I have an array of polylines that I am displaying on a map, now what I am aiming to do is, when I hover over a certain polyline from the list, only that polyline highlights (or changes color). What I have right now is something like this (this code is inside a loop that goes to the end filling polyLineArray with individual polyline data,
var pointList = [];
// pointList is an array and lat/lngs
var polyLineProperties = {
color: 'red',
opacity: 1,
weight: 5,
clickable: true
}
var polyLine = new L.polyline(pointList, polyLineProperties);
polyLine.on('mouseover', function() {
// WHAT TO DO HERE to HIGHLIGHT that specific polyline.
});
polyLineArray.push(polyLine);
Hope someone could help me with this, it'll be nice, if someone could even advice on how to alter any property of a polyline and not just color.
Thank you and awaiting your replies :)

Okay,
Sorry but I've managed to figure this one out, thanks to the tutorial on the following link,
Interactive Choropleth Map
This is all that was required,
polyLine.on('mouseover', function(e) {
var layer = e.target;
layer.setStyle({
color: 'blue',
opacity: 1,
weight: 5
});
});
Thank you all for reading.

Related

Trigger event on multiple features when hovering over any of those in leaflet

I have a layer with two polylines and polylineDecorators. I would like to highlight both polylines and polylineDecorators when I hover on any of these. Right now I'm able to highlight only one at the time when hovering on it.
Here is my code:
var layer_migration = L.layerGroup({
layerName: 'layer_migration',
pane: 'linesPane',
});
function onEachFeature_migration (feature, layer) {
var polyline = L.polyline(layer.getLatLngs(),{
color: "#8B0000",weight: 5,opacity: 0.4,dashArray: '8,8',
dashOffset: 0
}).addTo(layer_migration);
var PLdecorator1 = L.polylineDecorator(polyline, {
patterns: [{
offset: '104%',
repeat: 100,
symbol: L.Symbol.arrowHead({pixelSize: 16,
pathOptions: {color: "#8B0000",fillOpacity: 0.6,weight: 0
}
})
}]
}).addTo(layer_migration)
var myfeatures = L.featureGroup([polyline,PLdecorator1]).addTo(layer_migration);
myfeatures.on('mouseover', function(e) {
var layer = e.target;
layer.setStyle({color: '#8B0000',opacity: 1,fillOpacity:1
});
});
}
Any help super appreciated.
Thanks,
P
In your mouseover callback, I think that e.target will just refer to the individual layer (polyline or decorator) that triggered the event, not the collection of layers that make up the feature group. I've not tested it, but according to the docs, you ought to be able to get the effect you want by calling .setLayer() on the feature group itself:
myfeatures.on('mouseover', function(e) {
myfeatures.setStyle({color: '#8B0000',opacity: 1,fillOpacity:1});
});
Also, if the two polylines are created by two separate calls to onEachFeature_migration(), then they will end up as two separate feature groups. To get around this, you might need to assign an empty featureGroup to myfeatures outside the function, then add the new polylines to it inside the function using myfeatures.addLayer().

Leaflet polylines not working

I'm trying to show Polylines in Leaflet but it doesn't seem to work. Am I missing anything or...? p.s. Coordinate pairs do not contain the same values, so it should yield lines...
//this adds markers to the map, which works
var d = {};
d.coordinates = [[lat,lng],[lat,lng]]
var latLngs = d.coordinates.map(function (c) {
var marker = L.marker(c).addTo(map);
return {
lat: c[0],
lng: c[1]
};
});
//This 'should' add polylines but doesn't ...
var polyline = L.polyline(d.coordinates, { color: 'red', weight: 12 }).addTo(map);
I tried all sorts of variations on the code above, varying with instantiation/factory method like: new L.polyline() vs L.polyline() and trying upper- and lowercase Polyline. I tried passing arrays of [double, double] and [L.LatLng, L.LatLng] and even [{lat:lat,lng:lng}] but nothing seems to work... I really must be overlooking a simple thing...
I'm using Leaflet 0.7.
Edit:
As shown in the jsFiddle by ghybs it should work. I updated my code to the following:
var firstpolyline = L.polyline(d.coordinates, {
color: 'red',
weight: 12
}).addTo(map);
I also added identical logging statements in both the jsFiddle and my solution.
console.log(firstpolyline); //polyline for jsFiddle
console.log(map);
console.log(d.coordinates);
Those yield this (left is custom solution which is not showing a line, right is jsFiddle which is showing a line). Manually copy-pasting different coordinates pairs of my solution to the jsFiddle just works...:
I'm really lost here :(
There is no reason to add an extra .polyline after the factory L.polyline().
var polyline2 = L.polyline(d.coordinates, {color: 'red', weight: 12}).addTo(map);
Demo: http://jsfiddle.net/ve2huzxw/48/
Side note: you should use a single equal sign (=) for assignment in d.coordinates == [[lat,lng],[lat,lng]]

Leaflet: how to change map center and zoom level clicking on circleMarker?

I'm working on a map with a few circleMarkers. When a user is clickin on one of this circleMarker, I would like to center the map on this circleMarker and to zoom in. It works when I try this on multipolygon layers, but I didn't succeed on circleMarkers. Does anyone can help me?
Here is the code for my circleMarkers:
<script>
var map = L.map('map', {
center: [41.8, 12.5],
zoom: 5,
zoomControl:true, maxZoom:15, minZoom:4,
});
var feature_group = new L.featureGroup([]);
var raster_group = new L.LayerGroup([]);
var basemap = L.tileLayer('http://server.arcgisonline.com/ArcGIS/rest/services/World_Shaded_Relief/MapServer/tile/{z}/{y}/{x}', {
attribution: 'Tiles © Esri — Source: Esri',
});
basemap.addTo(map);
function style1(feature) {
return {
weight: 2,
radius: 10,
opacity: 1,
color: 'black',
weight: 1,
fillOpacity: 1,
fillColor: 'red'
};
}
L.geoJson(villes, {
style: style1,
pointToLayer: function (feature, latlng)
{
return L.circleMarker(latlng).bindLabel( feature.properties.Name, {className: "ville", noHide: true });
}
}
)
.addTo(map)
.showLabel;
</script>.
Here is a link to the complete map.
Thank you.
This can be achieved really simply.
Let's assume marker points to your leaflet marker and map to your leaflet map.
Quick way (recommended)
marker.on("click", function(event) {
map.setView(marker.getLatLng(), 16);
}, marker);
Here, I don't even compute the needed zoom level, because I assume leaflet will have to zoom to its max level anyway.
I could also have added my marker to a L.LayerGroup, even if the main point of a LayerGroup is to group multiple markers.
Anyhow, the more precise way
marker.on("click", function(event) {
map.setView(marker.getLatLng(), map.getBoundsZoom(layerGroup.getBounds());
}, marker);
Note that the quick way will do it nicely too. The second solution might seem more precise but it also slower, and implies a use of LayerGroup which is not the way it has been designed to work (create a new layergroup for each marker).
Don't forget to take yout time reading the docs, it's well-designed and pretty easy to understand.
I find the solution:
function onClick(e) {map.setView(this.getLatLng(),15);}
L.geoJson(villes, {
style: style1,
pointToLayer: function (feature, latlng)
{
return L.circleMarker(latlng).bindLabel( feature.properties.Name, {className: "ville", noHide: true }).on('click', onClick);
}
}
)
.addTo(zoom1)
.showLabel;
Thanks Stranded Kid for your help.

How to apply css on polylines : leaflet

I am working with the application which uses leaflet api.
Introduction
I needed to draw different types of fences, using decorators i can somewhat apply good visuals to the polylines but not much.
Problem
I was willing to show twisted wires instead of dashes, dots or plain lines and I know the twisted wire line will be an image but can't find help about applying custom css to polylines.
Script Example
var fence2Icon = L.icon({
iconUrl: 'xxxx.png',
iconSize: [5, 20]
iconAnchor: [5, 18]
});
// Add coordinate to the polyline
var polylineFence2 = new L.Polyline([], { color: 'red' });
function fencePlace2(e) {
// New marker on coordinate, add it to the map
new L.Marker(e.latlng, { icon: fence2Icon, draggable: false }).addTo(curr);
// Add coordinate to the polyline
polylineFence2.addLatLng(e.latlng).addTo(curr);
var decorator = L.polylineDecorator(polylineFence2, {
patterns:[{offset:5,repeat:'20px',symbol:new L.Symbol.Dash({pixelSize:5})
}]
}).addTo(curr);
}
L.easyButton('fa-flash', function () {
$('.leaflet-container').css('cursor', 'crosshair');
map.on('click', fencePlace2);
polylineFence2 = new L.Polyline([], { color: 'red' });
}).addTo(map);
If someone know anything about polyline or another way please do help.
Thanks for your time:-)
You can add a class in the options of your polyline ...
var polyline = L.polyline(latlngs, { className: 'my_polyline' }).addTo(map);
and add your own settings in the CSS ...
.my_polyline {
stroke: green;
fill: none;
stroke-dasharray: 10,10;
stroke-width: 5;
}
Here is an example: http://jsfiddle.net/FranceImage/9dggfhnc/
You can also access some options directly ...
var polyline = L.polyline(latlngs, { dashArray: '10,10' }).addTo(map);
See Path Options
If you create a polyline you're in fact adding an element to the SVG element which Leaflet uses to draw it's overlays. Styling SVG path elements is different from styling regular HTML elements. There's no such thing as border and background-color etc. It has different properties, if you're interested here's a nice read on the matter:
https://developer.mozilla.org/en-US/docs/Web/SVG/Tutorial/Fills_and_Strokes
You can style Leaflet's path elements when you instanciate them via options or via CSS using the properties (related to styling) described in the documentation here:
http://leafletjs.com/reference.html#path
Via options:
new L.Polyline([...], {
weight: 3,
color: 'red',
opacity: 0.5
}).addTo(map);
Via CSS:
new L.Polyline([...], {
className: 'polyline'
}).addTo(map);
.polyline {
weight: 3,
color: red,
opacity: 0.5
}
However, what you want, using an image simply isn't possible. You can use images as fill for SVG paths, but it would be impossible for your usecase. You'de need to add a pattern definition to the SVG Leaflet is using and then you could use that id as the fill property as outlined in this answer:
https://stackoverflow.com/a/3798797/2019281 but will always fill/tile the image horizontally which won't work if your polyline is vertical.

Leaflet: Removing markers from map

I load some lat / lon info, then use it to build a polyline.
I then want to add a marker at each of the polyline vertices that will show when the polyline is clicked.
The vertices should disappear if a different (or the same) polyline is clicked.
The code below creates the polyline and the vertex markers.
But the vertex markers do not ever disappear.
I've tried to do this several ways with the same result. I've tried storing the vertex markers in an array and adding them directly to the map, then map.removeLayer'ing them. That doesn't work either. Nor does it work if I use an L.featureGroup instead of a layerGroup.
Clearly I've missed the point somewhere as to how markers can be removed. Could someone point me at the error in my methodology?
// trackMarkersVisible is a global L.layerGroup
// success is a callback from an ajax that fetches trackData, an array f lat/lon pairs
success: function (trackData) {
// build an array of latLng's
points = buildTrackPointSet(trackData, marker.deviceID);
var newTrack = L.polyline(
points, {
color: colors[colorIndex],
weight: 6,
clickable: true
}
);
$(newTrack).on("click", function () {
trackMarkersVisible.clearLayers();
$.each(points, function(idx, val) {
var tm = new L.Marker(val);
trackMarkersVisible.addLayer(tm);
});
map.addLayer(trackMarkersVisible);
});
}
Without a JSFiddle or Plunker it's hard to say because i'm not sure what behaviour your getting but using the clearLayers() method of L.LayerGroup should remove all layers from that group. I would check in the onclick handler if the group already has layers: group.getLayers().length === 0 If the group is empty, add the markers, if the group has layers use clearLayers. Example in code:
polyline.on('click', function (e) {
if (group.getLayers().length === 0) {
e.target._latlngs.forEach(function (latlng) {
group.addLayer(L.marker(latlng));
});
} else {
group.clearLayers();
}
});
This works for me, see the example on Plunker: http://plnkr.co/edit/7IPHrO?p=preview
FYI: an instance of L.Polyline is always clickable by default so you can leave out the clickable: true