Re: [Geotools-gt2-users] how to detect the map coordinate when using the direction keys

[Trevor S. <ts...@ty...>]

On Sat, 2005-07-09 at 18:26 +0000, Zekeng liang wrote:
> I have a problem to detect the map coordiante when moving the map . I  load 
> part of the sptial map data initially, and I want to detect the map 
> coordiante show that I can know when the map will move out of the map pane 
> and load the new part of the map from the database.
> I know that we can use GeoMouseEvent to get the map coordiante by click on 
> the map pane; but how to get the map coordiante when using key event?
> 
What you should do is listen to events fired by the SyledMapPane
whenever the bounds are changed.  In the listener, load your new
features into your existing layer (e.g. a MemoryDataStore) and the
StyledMapPane will automatically update.

        zoomListener = new ZoomChangeListener() {
            public void zoomChanged(ZoomChangeEvent arg0) {
                    Rectangle2D rect = mapPane.getVisibleArea();
                    Envelope area = new Envelope(rect.getMinX(),
rect.getMaxX(), rect.getMinY(), rect.getMaxY());
		    loadFeatures(area);
            }
        };
mapPane.addZoomListener(zoomListener);

You must define loadFeatures(area), natch.
-- 
Trevor Stone | Software Engineer | tel 800-554-4434 ext 208 | fax 303-271-1930 | email ts...@ty...
Tyler Technologies | Eagle Division | 14142 Denver West Pkwy Suite 155 | Lakewood, CO 80401 | www.tyler-eagle.com