Using an id instead of a class here is important because Leaflet will expect an id to be passed to it for placing the map. The map div will need to exist in the DOM before you can reference it to create your map. This is possible during the AfterViewInit lifecycle hook. In this function, you will need to create a new Leaflet map object. The API allows you to define options in it as well. The center will be the geographic center of the contiguous United States located at The decimal coordinate system Leaflet uses assumes that anything to the west of the prime meridian will be a negative number, so the actual center coordinates will be [ Declare a variable for the map object, create the map, and call it from ngAfterViewinit :.
Next, open up app. With Leaflet, you visualize data as Layers. Save your changes. Then, stop your application and relaunch it. Open the application in your web browser localhost and observe the markers for the state capitals:. In this next step, you will change the markers from icons to circles. Then scale the size of the circles to reflect the population of the state capitol.
It will be very similar to the makrCapitalMarkers function. This object can contain a radius property. This function takes in a value population , a max value maximum population , and returns a radius in the range [0 - 20].
You will use the spread-operator and map to find the capital with the largest population:. Open the application in your web browser localhost and observe the new scaled circle markers for state capitals:. To install latest the Angular CLI, open a terminal and run the following command:. Let create a project to demonstrate an example of how to add a leaflet map in the angular 10 projects. We need to install our leaflet and leaflet-ant-path library in our project. Angular leaflet ant-path will display the path by latitude and longitude which we set.
For the map to render correctly, we need to import the Leaflet stylesheet to the Angular project. To do this import leaflet style in styles. Using that and file-saver, I was able to output the full image and regions, as follows:.
This worked brilliantly, except for one problem - the regions are rendering on the canvas clipped in the wrong position. That is, the region offset is wrong. Here is an example. The bottom and right of the map should be covered to the edge with coloured choropleth regions:. Edit: I had a look at an issue on the html2canvas site here which looked promising. Mine doesn't seem to have a transform problem as such, but there was someone that experienced the what I thought was a layer offset problem.
I implemented their solution here:. It's not really a layer offset problem I'm experiencing, but a layer clipping problem. Had the same issue recently, also went to the same quoted topic while trying to manage html2canvas.
In my case and maybe so do you , map was dynamic and carrying too many tiles and kind of elements markeclusters, piecharts, etc. It was messed up using the trick given by CraigVA. Leaflet Easy Print. I have done a fair bit of work on shifting the geojson to marry up the viewport with the background tiles, from the html2canvas link above. I did get it to correctly map if I moved the map around, but not when I zoomed.
It's very tricky and something I'd prefer not to do if I can avoid it. It's probably the worse way to do this, as if leaflet changes, the solution will break. Leaflet Easy Print gives me nothing extra over what dom-to-image gives me. There are errors in the console with dom-to-image, and the same errors appear when using leaflet easy print. At the bottom of the page we will have a button that calls a function in the TypeScript code to pan the map on a specific location.
With the scaffolding in place we can now focus on map. The map object will be configured to center the map on a latitude and longitude over Europe. Besides those properties the most important part of the initialization is the first parameter, 'map'.
This value matches up to the ID field in one of the map. Before anything can be displayed we also need to let Leaflet know where to retrieve the tiles for the map. These can be road maps, start charts, or any other image.
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