leaflet

问题 This is my state: const [markers, setMarkers] = useState([]) I initialise a Leaflet map in a useEffect hook. It has a click eventHandler. useEffect(() => { map.current = Leaflet.map('mapid').setView([46.378333, 13.836667], 12) . . . map.current.on('click', onMapClick) }, [] Inside that onMapClick I create a marker on the map and add it to the state: const onMapClick = useCallback((event) => { console.log('onMapClick markers', markers) const marker = Leaflet.marker(event.latlng, { draggable:

问题 Is there a way to add a polygon programmatically using the Leaflet draw plugin? https://github.com/Leaflet/Leaflet.draw For example: click a button and add a square that can be edited by the plugin. 回答1: You just need to add your polygon (or whatever other layer that you want to be editable) to the Feature Group that you pass to the edit.featureGroup option of your L.Control.Draw control. var editableLayers = L.featureGroup().addTo(map); var drawControl = new L.Control.Draw({ edit: {

问题 Actually i'm working with Leaflet but when i add a leaftlet.webglheatmap layer it uses the entire screen... I need to show only the data (colour) inside a geoJson polygon, instead of all the map: I talked with the webglheatmap developer but he told me to create a new shape with webgl, but that is not an option in this minute I tried Leaflet.Snogylop too, but it just draw a shape outside my map and with some colours it doesnt do the effect. Thanks in advice 回答1: If I am interpreting your

问题 I am attempting to clear a leaflet map in react when fetching new data to map, and i am unsure how to approach this. I saw this post but not sure how exactly to apply it. Right now I have a function that fetches 1 of 2 geojsons I have loaded. App.js //SWAP FILES AS EXAMPLE fetchData = () => { //MAP SHOULD CLEAR EVERYTIME NEW DATA IS FETCHED if(this.state.loaded === 1) { fetch( "https://raw.githack.com/datafaust/raw/main/cruise-prototype/hh_2020112300_2020120623_Saturday_02.geojson" ) .then(

问题 I am attempting to clear a leaflet map in react when fetching new data to map, and i am unsure how to approach this. I saw this post but not sure how exactly to apply it. Right now I have a function that fetches 1 of 2 geojsons I have loaded. App.js //SWAP FILES AS EXAMPLE fetchData = () => { //MAP SHOULD CLEAR EVERYTIME NEW DATA IS FETCHED if(this.state.loaded === 1) { fetch( "https://raw.githack.com/datafaust/raw/main/cruise-prototype/hh_2020112300_2020120623_Saturday_02.geojson" ) .then(

问题 I am highlighting a line on R leaflet using the following command library(leaflet) m = leaflet() %>% addTiles(group = "OpenStreetMap") x <- c(1,5,4,8) y <- c(1,3,4,7) data = sp::SpatialLines(list(sp::Lines(sp::Line(cbind(x,y)), ID="a"))) addPolylines(smoothFactor = 0.4, map = m, data=data, opacity = 0.3, weight = 2, color = "black", label = "text", popup = "text1", highlightOptions = highlightOptions(bringToFront = TRUE, opacity = 1, weight = 5, sendToBack = FALSE, color = "white")) Is there

问题 I'm working on an app with a large number of markers and would like to cluster them. I found Leaflet.markercluster and it does a good job. However, I would like to customize the clustering of the markers. Specifically, I want to cluster my markers depending on the country they are in. I don't want a cluster which includes all markers in Europe but instead several clusters by country. Is there any way to achieve this? 回答1: You can create several clusters and add your markers to them

问题 I'm trying to achieve having markers on a CRS map (specifically a circular avatar with initials) that scale with the map's zoom (they would appear larger or smaller depending on the zoom, not remain the same size), and have been having considerable difficulty achieving performance. I've tried two different components for the avatars, (still not sure which is right solution): Circle component with a simple, permanent tooltip inside (this component is convenient because it automatically scales)

问题 I'm trying to achieve having markers on a CRS map (specifically a circular avatar with initials) that scale with the map's zoom (they would appear larger or smaller depending on the zoom, not remain the same size), and have been having considerable difficulty achieving performance. I've tried two different components for the avatars, (still not sure which is right solution): Circle component with a simple, permanent tooltip inside (this component is convenient because it automatically scales)

问题 I'm trying to achieve having markers on a CRS map (specifically a circular avatar with initials) that scale with the map's zoom (they would appear larger or smaller depending on the zoom, not remain the same size), and have been having considerable difficulty achieving performance. I've tried two different components for the avatars, (still not sure which is right solution): Circle component with a simple, permanent tooltip inside (this component is convenient because it automatically scales)