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Re: [udig-devel] Feature Selection using example 
Hi Peter,
As I expect you know the function Layer#getFilter() returns the filter that represents the current selection for the layer. If it is returning Filter.ALL that means no features are selected. Try selecting something with the selection tool and then run your operation. It should return some features. As an experiment pass in a different filter to the line: 


Query query = new DefaultQuery(layer.getSchema().getTypeName(),
layer.getFilter(),new String[]{"the_geom"});
a Filter.NONE perhaps. This will verify that the code works. If you are selecting features using a command then you must keep in mind that commands are run in a separate thread and in that case the layer's filter may not have been updated by the time this code has ran. If you are using commands to set the selection then you can use map.#sendCommandSync(). 

Hope one of these tips help,

Jesse

On 25-Jan-07, at 8:02 AM, ukpete wrote:



Hello all,
Having a problem using the example (taken from this glorious list) returning 
a collection of features
for the current layer. Basically it always returns a collection of size 0. 

Here is the method I'm using :

public FeatureCollection getFeaturesSelectedOnLayer ()
	{
		net.refractions.udig.project.internal.Map currentMap =
ApplicationGISInternal.getActiveMap();
Layer layer = currentMap.getEditManagerInternal().getSelectedLayer (); 
		Query query = new DefaultQuery(layer.getSchema().getTypeName(),
layer.getFilter(),new String[]{"the_geom"});
		FeatureIterator featureIterator = null;
		FeatureCollection features = null;
		try{
	        IProgressMonitor monitor = new NullProgressMonitor();
	        FeatureSource featureSource =
layer.getResource(FeatureSource.class, monitor);
	        features = featureSource.getFeatures(query);
	        featureIterator = features.features();
aLogger.info("features selected are : " + features.size() + "type 
name is " + layer.getSchema().getTypeName() + "..is selectable? " +
layer.isSelectable());
	        while(featureIterator.hasNext() )
		    {
	        	Feature feature = featureIterator.next();
		        aLogger.info("Feature selected is : " +
feature.getAttribute("the_geom").toString());
		
		    }
		}
        catch (Exception e)
        {
        	e.printStackTrace();
        }
        finally
        {
        	if (featureIterator != null)
        	{
        		featureIterator.close();
        	}
        }

        return features;
	}

If I just call the getFeatures() method - without the query, all the
features on that layer are returned correctly. Any idea what I am doing 
wrong?

Thanks again for taking the time to read this.

Pete Cornwell
--
View this message in context: http://www.nabble.com/Feature- Selection-using-example-tf3116329.html#a8632047 
Sent from the udig-devel mailing list archive at Nabble.com.

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