Latest Contributions by PatrickMcKinney1

I'm developing a Shortlist Story Map application that has 9 tabs.  Based upon an issue with a separate shortlist app, I have wrapped the `initMap(layers)` call around line 586 of the `main.js` file in a setTimeout function to ensure the layers load. For non-mobile devices there is a loading icon.  However, for mobile devices, there is no loading icon.  The user will see the plain background until the tabs load. I was wondering if anyone had some code snippets to add in a loading icon for mobile versions of the app?  It would improve the user experience. I am using version 1.4.9 of Shortlist.  Here is the development site for the app.  I appreciate any help or nudging anyone can provide! ... View more

I started developing an application using the 2.2 version of WebApp Builder Developer Edition.  I had been using version 2.0. In both the local environment and when deployed to a live server, the app is forcing HTTPS.  Is there a way to change individual apps or WAB in general to not force HTTPS? Thanks, Patrick ... View more

I have been developing data visualization web mapping applications for various Cumberland County departments using the Leaflet JavaScript library.  All of these apps have used the standard WGS84 Web Mercator Auxiliary Sphere projection/tiling scheme.  This is used in Google Maps, ArcGIS Online, and the other major web map players. And while this works just fine, I wondered if there was a way to build web maps using the custom projection and tiling scheme we use for our tiled map services.  It turns out there is - but it requires a few plugins. The first is Proj4js, which “ transform point coordinates from one coordinate system to another, including datum transformations.”   The second is Proj4Leaflet, which “makes it possible to use projections and CRS not built into Leaflet.”  CRS stands for Coordinate Reference System. I thought I would share the process for using Esri REST services with custom projections/tiling schemes in a Leaflet web map.  You can find the example on CodePen. When I was learning how to do this, I referenced the example from the Esri Leaflet documentation site.  We’ll use Cumberland County’s 2015 Existing Land Use service for this demo. The service uses the Pennsylvania State Plane South (ft) projection, or EPSG 2272 as it is also known.  The spatial reference for your Esri REST service can be found at the service’s endpoint URL. You can get the information for your specific projection from the Spatial Reference website.  Here is sample of what you’ll get from this website to construct the custom CRS for your service: +proj=lcc +lat_1=40.96666666666667 +lat_2=39.93333333333333 +lat_0=39.33333333333334 +lon_0=-77.75 +x_0=600000 +y_0=0 +ellps=GRS80 +datum=NAD83 +to_meter=0.3048006096012192 +no_defs We also need some information about the service itself.  This includes the origin, and resolution for each zoom level.  These can also be found at the service’s endpoint URL.  Below is an image showing where this information is located:     Here is the code snippet for creating the custom CRS for the Existing Land Use service:     var spcPACrs = new L.Proj.CRS( 'EPSG:2272', '+proj=lcc +lat_1=40.96666666666667 +lat_2=39.93333333333333 +lat_0=39.33333333333334 +lon_0=-77.75 +x_0=600000 +y_0=0 +ellps=GRS80 +datum=NAD83 +to_meter=0.3048006096012192 +no_defs', { origin: [-1.192142E8, 1.461669E8], resolutions: [ 260.41666666666663, 86.80555555555556, 43.40277777777778, 20.833333333333332, 10.416666666666666, 6.944444444444444, 4.166666666666666, 2.083333333333333, 1.0416666666666665, 0.5208333333333333 ] });‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   Now that we have created our custom CRS, we can construct the service.  We will be using the tiledMapLayer class from the Esri Leaflet library.  It should be noted that by default, you can only use this class for tiled map services that use the WGS84 Web Mercator Auxiliary Sphere projection.  You need the above referenced plugins to use other projections/tiling schemes.   var ccpaELU = L.esri.tiledMapLayer({ url: '//gis.ccpa.net/arcgiswebadaptor/rest/services/ELU/MapServer', maxZoom: 8, minZoom: 0, continuousWorld: true, attribution: 'Cumberland County', errorTileUrl: '//downloads2.esri.com/support/TechArticles/blank256.png' }).addTo(map);‍‍‍‍‍‍‍‍   Some of the options you can set are the minimum and maximum zoom levels for the service.  The numbers should match the Level ID numbers found at the service’s endpoint URL.   You also have options to set an image for any places where the tiles fail to load.  As the tiledMapLayer inherits from Leaflet’s tileLayer class, all of it’s options can be used with the tiledMapLayer.   Hopefully you have found this article helpful.  To see this example in action, please visit the CodePen site.         ... View more

I wanted to share some websites I've found helpful in getting icons for WebApp Builder widgets and the loading screen.  Feel free to share other sites you use. Font Awesome to PNG - Create a .png version of Font Awesome icons.  You can choose the color and size. Loading.io - Create loading icons (gif, svg).  This is great for the loading screen icon when WAB first loads. ... View more

Is there a way to limit how many records can be exported to CSV from the Attribute Table widget? If not, is there a way to limit how many records can be returned from a query on the service itself? Thanks, Patrick ... View more

I've created an ArcGIS Online group for us to share our maps/apps developed with Leaflet and the ESRI Leaflet plugins: http://www.arcgis.com/home/group.html?id=ee3f08a75a1e4d82a18ef6972e28ef81    I'm hoping we can inspire each other, and even help each other on our projects.   Thanks,   Patrick ... View more

Here's a demo of 2 ways to add GeoJSON to a Leaflet web map: http://codepen.io/pmckinney/pen/mELyNY   I know there is also the Leaflet-AJAX plugin.   And if you're interested in converting a shapefile or feature class to GeoJSON, check out the City of Philadelphia's ArcToolbox.   Does anyone know why the output of the ArcGIS Desktop JSON conversion tool does not work in Leaflet?  I've always wondered what was going on with this. ... View more