Creating Component/Widget Libary without MapViewer

DylanRoy

Hello,

I would like to create a component library that can interface with the ESRI ArcGIS library. I have already added some actionscript components that allow for the user to drag visual components onto the mxml in the design view. I am unable to create a custom component that can retrieve data from ESRI's map widget. I don't want to be forced make handlers for the ESRI components that are already there.

Deliverable:
A library that can interface with ArcGIS library and allows for components to be dropped into the mxml when in the design view of Flash Builder like ESRI's already existing Map components.

A sample workflow for this would be:
1. Drop Esri's Map component and set the source.
2. Drop custom component(i.e. latlog detector)

If anything is unclear please let me know.

Thanks!

Drew

dkroy,

Glad it worked so well.

If you wanted to take it one step further you could create a base component that contains the map as a default property and have some error checking built in place to ensure its added at runtime.

Then you would simply extend that base class for each new component you build. This would save you some time creating new components and ensure each components checked for the map property to be set and is named the same across your entire library.

An example of a base component might be:

package
{
 import com.esri.ags.Map;
 import mx.controls.Alert;
 import mx.events.FlexEvent;
 
 import spark.components.Group;
 
 public class BaseMapComponent extends Group
 {
  private var _map:Map;
  public function get map():Map
  {
   return _map;
  }
  
  public function set map(value:Map):void
  {
   _map = value;
  }
  
  public function BaseMapComponent()
  {
   super();
   this.addEventListener(FlexEvent.CREATION_COMPLETE, onCreationComplete);
  }
  
  private function onCreationComplete(event:FlexEvent) :void
  {
   validateMapPropertyIsSet();
  }

  private function validateMapPropertyIsSet():void
  {
   if (map == null)
   {
    Alert.show("Map property for  (" + this.className + ") is not set. This tool may not work coorectly");
   }
  }
 }
}

If you wanted to get even more fancy you could check if the map property is set and if not try and find the map component by looping through the applications children recursively.  This functionality would not be good if you were planning on having more than one map on the stage though... and it could be problematic, but may be worth a test.

Attached is a new sample that contains the base map component i described above. I would suggest going this way and extend it  as needed.. It may be helpful too because if you are into skinning it might save time on that end too.

Good luck,

Drew

MyComponents.zip