Strange blue border in MapView of ArcGIS JS 4

Starting from ArcGIS JS 4.x, under some special conditions, the MapView will have a blue border when the MapView is focus, who genius get this geneless idea?

To get rid of this stupid box, style the following:

.esri-view-surface--inset-outline::after {   
    outline: none !important;
    padding: 0px !important;
}

So when this stupid design will come out? When ever your HTML got the following conditions, that stupid box will be shown when MapView is on focus:

body {
    margin: 0;
} 

#mapDiv {
    width: 100%
}

... The most weird API ever encountered

Updating graphic in ArcGIS JS 4.x GraphicsLayer

Esri still don't have a clue on how to modify a graphic in GraphicsLayer directly at version 4.8.

You still need to clone the graphic, remove the existing one, and add the new one to realize the modification.

Ref:

https://developers.arcgis.com/javascript/latest/guide/functionality-matrix/index.html#graphicslayer

Stone age API.

Map server URL with query parameters in ArcGIS JS 4.6

Starting from ArcGIS JS 4.6, the map server URL should not have any query parameters. Any query parameters exists in the map server URL will be removed.

To handle this issues, you can override the urlUtils.removeQueryParameters() as below


require(["esri/core/urlUtils"], function(urlUtils) {

   urlUtils.removeQueryParameters = function(a){
      return a;
   };

});

But somehow that's a bad trick. A better way is to use the TileLayer._set() to get rid of the parameters stripping action when setting the URL. i.e.

TileLayer._set('url', 'map_server_url')

Using Proxy with ArcGIS JS

For servers without CORS enabled. We can use proxy mechanism to access the services.

This is done by modifying the proxy.ashx.

You can also add any parameters before sending the request to the actual server.

More references could be found at:

https://developers.arcgis.com/javascript/latest/guide/proxies/index.html

OpenLayers blurry map with ArcGIS tiles

Check this out:

https://github.com/openlayers/openlayers/issues/6430

Leaflet vs ArcGIS JS / FeatureLayer

I'd been deciding ESRI-Leaflet or ArcGIS JS for a small project. Some findings for our references:

When using FeatureLayer for plenty amount of data (e.g. vast amount of points), ArcGIS JS performs better than Leaflet. So even the file size of Leaflet is far smaller than ArcGIS JS, I still have to choose the larger one.

Hope Leaflet FeatureLayer performance can boost up in future.

ArcGIS: Query for a simplified feature set

To query a simplified feature set using QueryTask, you can set the "MaxAllowableOffset" property through

          com.esri.core.tasks.ags.query.Query.setMaxAllowableOffset( )

or if you're using ArcGIS Android SDK version 10.2.4 already, then it should be:

          com.esri.core.tasks.ags.query.QueryParameters.setMaxAllowableOffset( )

ArcGIS Server Cached Map Expiry Time

The tiled cached map expire time can be controlled by a variable "cacheControlMaxAge" in ArcGIS Server Administrator Directory, available starting at ArcGIS for Server (Window) 10.2.

Ref: http://resources.arcgis.com/en/help/main/10.2/index.html#//015400000577000000

The default HTTP header "max-age" is 86400 (i.e. 24 hours), which seems cannot be changed in ArcGIS Server 10.0.

For Android SDK 10.2, the map caching activities only works on the particular session. That means when the user quit the app and start it again. The previous cache will not be used.

Customize the 404 page for ArcGIS Server Map Services

ArcGIS Server 10 internal Tomcat web root:
       \ArcGIS\Server10.0\java\manager\web_output

ArcGIS Server 10 internal Tomcat conf:
       \ArcGIS\Server10.0\java\manager\service\managerappserver\conf

You may modify the web.xml by adding the error page definition:

        ...

        <welcome-file-list>

            <welcome-file>index.html</welcome-file>

            <welcome-file>index.htm</welcome-file>

            <welcome-file>index.jsp</welcome-file>

        </welcome-file-list>

        <error-page>

            <error-code>404</error-code>

            <location>/404.htm</location>

        </error-page>

    </web-app>

And the 404 error file can put in the root (/web_output)

Remove the "Zoom to" link in Callout of ArcGIS Javascript API

We can add the following style to hide the "Zoom to" link:

      .action.zoomTo {
      display: none;
      }

Ref:
http://forums.arcgis.com/threads/89318-Remove-quot-Zoom-to-quot-link

ESRI ArcGIS JS API version 3.4 hiding the Dojo Dnd style "dojoDndAvatar"

For ArcGIS JS API v3.4, if you include "esri.css" in your project, then your Dojo Dnd Avatar (the floating hints while you're doing drag and drop) will be disappeared.

Why? Because in "esri.css", esri.css got the following style:

     .dojoDndAvatar {display: none;}

God... What the hell ESRI guys are doing ?!

ArcGIS JS: Move a graphic to top

To move a graphic in a ArcGIS JS GraphicsLayer to top:

g.getDojoShape().moveToFront();

But this may breaks the onClick event of the GraphicsLayer, beware.

Updated: in ArcGIS JS API version 3.8, use getShape( ) instead. ESRI... no more stupid naming please...

Secure the ArcGIS Server

References for securing the ArcGIS server:

• http://blogs.esri.com/esri/arcgis/2010/06/23/five-things-to-consider-when-securing-arcgis-server/
• http://geochalkboard.wordpress.com/2010/12/13/using-a-proxy-page-with-the-arcgis-server-api-for-javascript/
• http://resources.esri.com/help/9.3/arcgisserver/apis/javascript/arcgis/help/jshelp/ags_proxy.htm#webprint

Using ArcGIS JS API v2.5 - v2.8

Some notes on using their API:

• In 2.5, the path is /library/2.5/arcgis (or arcgis_compact)
• In 2.6, the path changed to /library/2.6/jsapi (or jsapicompact), but the manual doesn't changed. So be careful when following the installation manual
• The file in /library/2.6/jsapi/js/esri/jsapi.js will create a Javascript error. You might need to replace the file content with the one in ESRI ArcGIS JS API production site.

Something more about the Javascript files in the API:

• The jsapi.js contains UTF8 characters (‰ - u8240, ¤ - u0164), when ArcGIS JS API "index.jsp" includes this file using <jsp:include>, the UTF8 characters will corrupted. I found two solutions for that
1. Modify the jsapi.js, swap those UTF8 characters back to escaped (\u) characters, and save the file back as ANSI format. OR
2. Modify the "index.jsp", avoid using <jsp:include>, try to use file reader with encoding specified. For example: FileUtils.readFileToString(new File(filepath_), "UTF8"); (where FileUtils is from org.apache.commons.io package)