Re: [udig-devel] Select Feature - Problem with PickTool code example

[Jody Garnett <jody.garnett@xxxxxxxxx>]

Good afternoon.

In your code example you are making a very small envelope (ie
rectangle) with 0 width and 0 height. The BBOX filter defined by the
OGC Filter specification is not really going to find anything inside
this small rectangle.

I usually try and make a rectangle the size of 2 pixels.

Also note that source.getFeatures() returns everything; you want to
use source.getFeatures( filter ) to process your query.

Jody

On Tue, Apr 7, 2009 at 1:38 AM, Rodolphe QUEMERAIS
<rodolphe.quemerais@xxxxxxxxx> wrote:
> Hi all,
> I'm starting to study uDig possibilities and achieve to do manythings now
> (create new layer, add features to a layer,...) programatically. My next
> step is to edit a feature after selected it on screen but I'm unable to
> select one.
> I've tested the PickTool code from uDig examples but got no result.
> I've traced results with some println.. The coordinates are good, and I do
> have the number of features count but nothing is selected.
>
> This is the code taken from uDig examples and the println I added to see if
> datas are ok.
> Help would be welcome.
>
>   @Override
>         protected void onMouseReleased( MapMouseEvent e ) {
>             try{
>
>                 // convert the mouse click into map coordinates.  This is
> the
>                 // CRS obtained from the ViewportModel
>                 Coordinate world = getContext().pixelToWorld(e.x, e.y);
>
>                 // now we must transform the coordinate to the CRS of the
> layer
>                 ILayer layer = getContext().getSelectedLayer();
>                 MathTransform tranform = layer.mapToLayerTransform();
>
>                 double[] from=new double[]{world.x, world.y};
>                 double[] to = new double[2];
>                 tranform.transform(from, 0, to, 0, 1);
> //I check if coordinates are ok
> System.out.println(to[0]);
> System.out.println(to[1]);
>                 // Construct a envelope from the transformed coordinate
>                 Envelope env = new Envelope(new Coordinate(to[0],to[1]));
>
>                 // Query the feature source to get the features that
> intersect with that coordinate
>                 FeatureSource source =
> layer.getResource(FeatureSource.class, ProgressManager.instance().get());
>                 FeatureCollection featuresFiltre =
> source.getFeatures(layer.createBBoxFilter(env,
> ProgressManager.instance().get()));
>                 FeatureCollection features = source.getFeatures();
> //show the number of features on the layer and the selected features
> System.out.println("Selected features on Layer : "+features.size());
> System.out.println("Selected features : "+featuresFiltre.size());
>                 // do something smart, notify user probably.
>             } catch (Throwable t) {
> System.out.println("Nothing !!!");
>             }
>
>
>
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