topic Re: map.units support in agslib-3.0pre-2012-03-15 in ArcGIS API for Flex Questions

map.units support in agslib-3.0pre-2012-03-15

TomSchuller — Mon, 16 Apr 2012 03:40:07 GMT

Hy,
I just wanted to migrate some widgets to the FlexViewer3.0.
Unfortantly, I'm blocked by the property "units" in the "Map" class.

In the "What's new" and "Migrating 2.5 to 3.0", I dont' find anything about a change on that property:
http://resourcesbeta.arcgis.com/en/help/flex-api/concepts/index.html#/What_s_new_in_ArcGIS_API_for_Flex/017p0000000w000000/
http://resourcesbeta.arcgis.com/en/help/flex-api/concepts/index.html#/Migrating_from_2_5_to_3_0/017p00000024000000/

In the API reference, I don't find a description for units:
http://resourcesbeta.arcgis.com/en/help/flex-api/apiref/com/esri/ags/Map.html#units
On the other side, reading the doc of the scale property, there is a relation to "units":
http://resourcesbeta.arcgis.com/en/help/flex-api/apiref/com/esri/ags/Map.html#scale

Is this a bug of a missed property or an undocumented change in the 3.0 api.

Thanks,
Tom

Re: map.units support in agslib-3.0pre-2012-03-15

IvanBespalov — Mon, 16 Apr 2012 05:24:45 GMT

Tom,
yes "units" property is not in reference (I do not know why), but it is String type property and it exists:

units property
units:String
The units of the Map.
These units are used for calculating the map scale. The default value is the units of the first layer added to the map.
This property can be used as the source for data binding.

map.units = Units.METERS;

see com.esri.ags.Units

Re: map.units support in agslib-3.0pre-2012-03-15

TomSchuller — Mon, 16 Apr 2012 05:40:09 GMT

It's not only missed in the reference, it's also missed in the library itself.

I can't use:

map.units

in my code.

Tom

Re: map.units support in agslib-3.0pre-2012-03-15

IvanBespalov — Sat, 11 Dec 2021 15:20:03 GMT

:confused:

it's also missed in the library itself

[ATTACH=CONFIG]13541[/ATTACH]

test:

protected function onWidgetOpen(event:Event):void
{
    Alert.show("Map units are: '" + map.units + "'", "onWidgetOpen");
}

[ATTACH=CONFIG]13542[/ATTACH]

No comments.

Re: map.units support in agslib-3.0pre-2012-03-15

TomSchuller — Mon, 16 Apr 2012 06:13:33 GMT

I'm on agslib-3.0pre-2012-03-15

Your version is on: beta1 2011-12-16

Tom

Re: map.units support in agslib-3.0pre-2012-03-15

IvanBespalov — Mon, 16 Apr 2012 06:16:49 GMT

Your version is on: beta1 2011-12-16

Tom, you're right. I did not pay attention to it.

Re: map.units support in agslib-3.0pre-2012-03-15

IvanBespalov — Sat, 11 Dec 2021 15:20:06 GMT

Map units are the first loaded layer units.
Until ESRI developers complete reference (or fix bugs), you can use first layer units:

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
      xmlns:s="library://ns.adobe.com/flex/spark" 
      xmlns:mx="library://ns.adobe.com/flex/mx" 
      xmlns:esri="http://www.esri.com/2008/ags">
 <s:layout>
  <s:VerticalLayout />
 </s:layout>
 <fx:Script>
  <![CDATA[
   import com.esri.ags.layers.ArcGISDynamicMapServiceLayer;
   import com.esri.ags.layers.Layer;
   
   import mx.collections.ArrayCollection;
   import mx.controls.Alert;
   
   
   protected function button1_clickHandler(event:MouseEvent):void
   {
    var layer:Layer = getMapFirstLayer();
    if (layer != null)
    {
     var message:String = "";
     if (layer is ArcGISTiledMapServiceLayer)
     {
      message = "Map units are: '" + ArcGISTiledMapServiceLayer(layer).units + "' - the first loaded layer units";
     }
     else if (layer is ArcGISDynamicMapServiceLayer)
     {
      message = "Map units are: '" + ArcGISDynamicMapServiceLayer(layer).units + "' - the first loaded layer units";
     }
     
     Alert.show(message, "Map units");
    }
   }
   
   private function getMapFirstLayer():Layer
   {
    if (map != null)
    {
     var mapLayers:ArrayCollection = map.layers as ArrayCollection;
     if (mapLayers != null && mapLayers.length > 0)
     {
      return mapLayers.getItemAt(0) as Layer;
     }
    }
    
    return null;
   }
   
  ]]>
 </fx:Script>
 <s:Button label="Show map units" click="button1_clickHandler(event)" />
 <esri:Map id="map">
  <esri:ArcGISTiledMapServiceLayer url="http://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer"/>
 </esri:Map> 
</s:Application>

Re: map.units support in agslib-3.0pre-2012-03-15

BjornSvensson — Mon, 16 Apr 2012 17:21:41 GMT

Is this a bug of a missed property or an undocumented change in the 3.0 api.

It's a yet-to-be documented change in the 3.0 API. Thanks for reminding us 🙂

We removed it because you no longer need to set it. Based on the spatial reference, the API will now automatically figure out the units for you.

Re: map.units support in agslib-3.0pre-2012-03-15

TomSchuller — Mon, 16 Apr 2012 17:41:52 GMT

Bjorn,
i agree that it's not important to set that property.

But I think it's useful to read out the information, either as:

readonly map property like: map.units

or readonly spatialreference property like: map.spatialReference.units

The spatialReference class has currently also no-property defined to read it out:
http://resourcesbeta.arcgis.com/en/help/flex-api/apiref/com/esri/ags/SpatialReference.html

I hope you can re-implement it in your API or give some way to access it.
If it will not be exposed as property, I will have to create a lookup-table for each spatialReferece-wkid.

Thanks,
Tom

Re: map.units support in agslib-3.0pre-2012-03-15

BjornSvensson — Mon, 16 Apr 2012 21:39:59 GMT

But I think it's useful to read out the information

Hi Tom,
I'm curious - what do you use it for? Just to display it to end user (seems a little unnecessary) - or do you need it for something else?

Re: map.units support in agslib-3.0pre-2012-03-15

TomSchuller — Tue, 17 Apr 2012 13:49:17 GMT

Hy,
I have written an advanced PrintWidget for the viewer.

You can find a demo here: http://gis.pch.etat.lu/flexViewerPrint/
The backend is a custom SOE.
The sources can be found here: http://bitbucker.schuller.lu

In fact, I need the "map.units" to calculate the current map extent based on the paper format and the map scale.
?? mapUnits = x paperUnits * mapScale

Tom

Re: map.units support in agslib-3.0pre-2012-03-15

TomSchuller — Fri, 01 Jun 2012 12:53:05 GMT

Hy,
did you have news if you reintegrate the property in the final Flex API version?

Tom

Re: map.units support in agslib-3.0pre-2012-03-15

DasaPaddock — Thu, 07 Jun 2012 18:34:51 GMT

Tom,

You can use Ivan's suggestion of getting the units from the first layer in the Map. This is all the Map was doing before unless it was explicitly set.

See:
http://forums.arcgis.com/threads/55275-map.units-support-in-agslib-3.0pre-2012-03-15?p=189991&viewfull=1#post189991