private static void constructMapUI(final File shapefile) {
JMapFrame frame;
MapContent map = new MapContent();
FileDataStore dataStore;
SimpleFeatureSource shapefileSource;
try {
dataStore = FileDataStoreFinder.getDataStore(shapefile);
shapefileSource = dataStore.getFeatureSource();
} catch (IOException e) {
e.printStackTrace();
return;
}
Style shpStyle = SLD.createPolygonStyle(Color.RED, null, 0.0f);
Layer shpLayer = new FeatureLayer(shapefileSource, shpStyle);
map.addLayer(shpLayer);
frame = new JMapFrame(map);
frame.enableLayerTable(true);
frame.setSize(1000, 800);
frame.enableStatusBar(true);
frame.enableToolBar(true);
frame.setTitle("Map Viewer (courtesy of GeoTools");
JMenuBar menuBar = new JMenuBar();
frame.setJMenuBar(menuBar);
frame.setVisible(true);
frame.setDefaultCloseOperation(JMapFrame.HIDE_ON_CLOSE);
}
/**
* This method connects to the shapefile; retrieves information about its features; creates a map
* frame to display the shapefile and adds a custom feature selection tool to the toolbar of the
* map frame.
*/
public void displayShapefile(File file) throws Exception {
FileDataStore store = FileDataStoreFinder.getDataStore(file);
featureSource = store.getFeatureSource();
setGeometry();
/*
* Create the JMapFrame and set it to display the shapefile's features
* with a default line and colour style
*/
MapContext map = new DefaultMapContext();
map.setTitle("Feature selection tool example");
Style style = createDefaultStyle();
map.addLayer(featureSource, style);
mapFrame = new JMapFrame(map);
mapFrame.enableToolBar(true);
mapFrame.enableStatusBar(true);
/*
* Before making the map frame visible we add a new button to its
* toolbar for our custom feature selection tool
*/
JToolBar toolBar = mapFrame.getToolBar();
JButton btn = new JButton("Select");
toolBar.addSeparator();
toolBar.add(btn);
/*
* When the user clicks the button we want to enable
* our custom feature selection tool. Since the only
* mouse action we are intersted in is 'clicked', and
* we are not creating control icons or cursors here,
* we can just create our tool as an anonymous sub-class
* of CursorTool.
*/
btn.addActionListener(
new ActionListener() {
public void actionPerformed(ActionEvent e) {
mapFrame
.getMapPane()
.setCursorTool(
new CursorTool() {
@Override
public void onMouseClicked(MapMouseEvent ev) {
selectFeatures(ev);
}
});
}
});
/** Finally, we display the map frame. When it is closed this application will exit. */
mapFrame.setSize(600, 600);
mapFrame.setVisible(true);
}
/**
* Sets the display to paint selected features yellow and unselected features in the default
* style.
*
* @param IDs identifiers of currently selected features
*/
public void displaySelectedFeatures(Set<FeatureId> IDs) {
Style style;
if (IDs.isEmpty()) {
style = createDefaultStyle();
} else {
style = createSelectedStyle(IDs);
}
// mapFrame.getMapContext().getLayer(0).setStyle(style);
// 这里有点问题，需调整
mapFrame.getMapPane().repaint();
}
/**
* This method is called by our feature selection tool when the user has clicked on the map.
*
* @param pos map (world) coordinates of the mouse cursor
*/
void selectFeatures(MapMouseEvent ev) {
System.out.println("Mouse click at: " + ev.getMapPosition());
/*
* Construct a 5x5 pixel rectangle centred on the mouse click position
*/
Point screenPos = ev.getPoint();
Rectangle screenRect = new Rectangle(screenPos.x - 2, screenPos.y - 2, 5, 5);
/*
* Transform the screen rectangle into bounding box in the coordinate
* reference system of our map context. Note: we are using a naive method
* here but GeoTools also offers other, more accurate methods.
*/
AffineTransform screenToWorld = mapFrame.getMapPane().getScreenToWorldTransform();
Rectangle2D worldRect = screenToWorld.createTransformedShape(screenRect).getBounds2D();
ReferencedEnvelope bbox =
new ReferencedEnvelope(
worldRect,
// mapFrame.getMapContext().getCoordinateReferenceSystem());
// 这里有点问题，需调整
mapFrame.getMapContent().getCoordinateReferenceSystem());
/*
* Create a Filter to select features that intersect with
* the bounding box
*/
Filter filter = ff.intersects(ff.property(geometryAttributeName), ff.literal(bbox));
// ff.bbox(ff.property(geometryAttributeName), bbox);
/*
* Use the filter to identify the selected features
*/
try {
FeatureCollection<SimpleFeatureType, SimpleFeature> selectedFeatures =
featureSource.getFeatures(filter);
FeatureIterator<SimpleFeature> iter = selectedFeatures.features();
Set<FeatureId> IDs = new HashSet<FeatureId>();
try {
while (iter.hasNext()) {
SimpleFeature feature = iter.next();
IDs.add(feature.getIdentifier());
System.out.println(" " + feature.getIdentifier());
}
} finally {
iter.close();
}
if (IDs.isEmpty()) {
System.out.println(" no feature selected");
}
displaySelectedFeatures(IDs);
} catch (Exception ex) {
ex.printStackTrace();
return;
}
}