001    // License: GPL. See LICENSE file for details.
002    package org.openstreetmap.josm.gui;
003    
004    import static org.openstreetmap.josm.tools.I18n.tr;
005    
006    import java.awt.AlphaComposite;
007    import java.awt.Color;
008    import java.awt.Graphics;
009    import java.awt.Graphics2D;
010    import java.awt.Point;
011    import java.awt.Rectangle;
012    import java.awt.event.ComponentAdapter;
013    import java.awt.event.ComponentEvent;
014    import java.awt.event.MouseEvent;
015    import java.awt.event.MouseMotionListener;
016    import java.awt.geom.Area;
017    import java.awt.geom.GeneralPath;
018    import java.awt.image.BufferedImage;
019    import java.beans.PropertyChangeEvent;
020    import java.beans.PropertyChangeListener;
021    import java.util.ArrayList;
022    import java.util.Collection;
023    import java.util.Collections;
024    import java.util.Comparator;
025    import java.util.Enumeration;
026    import java.util.LinkedList;
027    import java.util.List;
028    import java.util.concurrent.CopyOnWriteArrayList;
029    
030    import javax.swing.AbstractButton;
031    import javax.swing.ActionMap;
032    import javax.swing.InputMap;
033    import javax.swing.JOptionPane;
034    import javax.swing.JPanel;
035    
036    import org.openstreetmap.josm.Main;
037    import org.openstreetmap.josm.actions.AutoScaleAction;
038    import org.openstreetmap.josm.actions.mapmode.MapMode;
039    import org.openstreetmap.josm.data.Bounds;
040    import org.openstreetmap.josm.data.Preferences.PreferenceChangeEvent;
041    import org.openstreetmap.josm.data.Preferences.PreferenceChangedListener;
042    import org.openstreetmap.josm.data.SelectionChangedListener;
043    import org.openstreetmap.josm.data.coor.LatLon;
044    import org.openstreetmap.josm.data.osm.DataSet;
045    import org.openstreetmap.josm.data.osm.DataSource;
046    import org.openstreetmap.josm.data.osm.OsmPrimitive;
047    import org.openstreetmap.josm.data.osm.visitor.BoundingXYVisitor;
048    import org.openstreetmap.josm.data.osm.visitor.paint.PaintColors;
049    import org.openstreetmap.josm.data.osm.visitor.paint.relations.MultipolygonCache;
050    import org.openstreetmap.josm.gui.layer.GpxLayer;
051    import org.openstreetmap.josm.gui.layer.Layer;
052    import org.openstreetmap.josm.gui.layer.MapViewPaintable;
053    import org.openstreetmap.josm.gui.layer.OsmDataLayer;
054    import org.openstreetmap.josm.gui.layer.markerlayer.MarkerLayer;
055    import org.openstreetmap.josm.gui.layer.markerlayer.PlayHeadMarker;
056    import org.openstreetmap.josm.tools.AudioPlayer;
057    import org.openstreetmap.josm.tools.BugReportExceptionHandler;
058    
059    /**
060     * This is a component used in the {@link MapFrame} for browsing the map. It use is to
061     * provide the MapMode's enough capabilities to operate.<br/><br/>
062     *
063     * {@code MapView} holds meta-data about the data set currently displayed, as scale level,
064     * center point viewed, what scrolling mode or editing mode is selected or with
065     * what projection the map is viewed etc..<br/><br/>
066     *
067     * {@code MapView} is able to administrate several layers.
068     *
069     * @author imi
070     */
071    public class MapView extends NavigatableComponent implements PropertyChangeListener, PreferenceChangedListener, OsmDataLayer.LayerStateChangeListener {
072    
073        /**
074         * Interface to notify listeners of a layer change.
075         * @author imi
076         */
077        public interface LayerChangeListener {
078            
079            /**
080             * Notifies this listener that the active layer has changed.
081             * @param oldLayer The previous active layer
082             * @param newLayer The new activer layer
083             */
084            void activeLayerChange(Layer oldLayer, Layer newLayer);
085            
086            /**
087             * Notifies this listener that a layer has been added.
088             * @param newLayer The new added layer
089             */
090            void layerAdded(Layer newLayer);
091            
092            /**
093             * Notifies this listener that a layer has been removed.
094             * @param oldLayer The old removed layer
095             */
096            void layerRemoved(Layer oldLayer);
097        }
098    
099        public interface EditLayerChangeListener {
100            void editLayerChanged(OsmDataLayer oldLayer, OsmDataLayer newLayer);
101        }
102    
103        public boolean viewportFollowing = false;
104    
105        /**
106         * the layer listeners
107         */
108        private static final CopyOnWriteArrayList<LayerChangeListener> layerChangeListeners = new CopyOnWriteArrayList<LayerChangeListener>();
109        private static final CopyOnWriteArrayList<EditLayerChangeListener> editLayerChangeListeners = new CopyOnWriteArrayList<EditLayerChangeListener>();
110    
111        /**
112         * Removes a layer change listener
113         *
114         * @param listener the listener. Ignored if null or already registered.
115         */
116        public static void removeLayerChangeListener(LayerChangeListener listener) {
117            layerChangeListeners.remove(listener);
118        }
119    
120        public static void removeEditLayerChangeListener(EditLayerChangeListener listener) {
121            editLayerChangeListeners.remove(listener);
122        }
123    
124        /**
125         * Adds a layer change listener
126         *
127         * @param listener the listener. Ignored if null or already registered.
128         */
129        public static void addLayerChangeListener(LayerChangeListener listener) {
130            if (listener != null) {
131                layerChangeListeners.addIfAbsent(listener);
132            }
133        }
134    
135        /**
136         * Adds an edit layer change listener
137         *
138         * @param listener the listener. Ignored if null or already registered.
139         * @param initialFire Fire an edit-layer-changed-event right after adding
140         * the listener in case there is an edit layer present
141         */
142        public static void addEditLayerChangeListener(EditLayerChangeListener listener, boolean initialFire) {
143            addEditLayerChangeListener(listener);
144            if (initialFire) {
145                if (Main.isDisplayingMapView() && Main.map.mapView.getEditLayer() != null) {
146                    fireEditLayerChanged(null, Main.map.mapView.getEditLayer());
147                }
148            }
149        }
150    
151        /**
152         * Adds an edit layer change listener
153         *
154         * @param listener the listener. Ignored if null or already registered.
155         */
156        public static void addEditLayerChangeListener(EditLayerChangeListener listener) {
157            if (listener != null) {
158                editLayerChangeListeners.addIfAbsent(listener);
159            }
160        }
161    
162        protected static void fireActiveLayerChanged(Layer oldLayer, Layer newLayer) {
163            for (LayerChangeListener l : layerChangeListeners) {
164                l.activeLayerChange(oldLayer, newLayer);
165            }
166        }
167    
168        protected static void fireLayerAdded(Layer newLayer) {
169            for (MapView.LayerChangeListener l : MapView.layerChangeListeners) {
170                l.layerAdded(newLayer);
171            }
172        }
173    
174        protected static void fireLayerRemoved(Layer layer) {
175            for (MapView.LayerChangeListener l : MapView.layerChangeListeners) {
176                l.layerRemoved(layer);
177            }
178        }
179    
180        protected static void fireEditLayerChanged(OsmDataLayer oldLayer, OsmDataLayer newLayer) {
181            for (EditLayerChangeListener l : editLayerChangeListeners) {
182                l.editLayerChanged(oldLayer, newLayer);
183            }
184        }
185    
186        /**
187         * A list of all layers currently loaded.
188         */
189        private final List<Layer> layers = new ArrayList<Layer>();
190        /**
191         * The play head marker: there is only one of these so it isn't in any specific layer
192         */
193        public PlayHeadMarker playHeadMarker = null;
194    
195        /**
196         * The layer from the layers list that is currently active.
197         */
198        private Layer activeLayer;
199    
200        private OsmDataLayer editLayer;
201    
202        /**
203         * The last event performed by mouse.
204         */
205        public MouseEvent lastMEvent = new MouseEvent(this, 0, 0, 0, 0, 0, 0, false); // In case somebody reads it before first mouse move
206    
207        private LinkedList<MapViewPaintable> temporaryLayers = new LinkedList<MapViewPaintable>();
208    
209        private BufferedImage nonChangedLayersBuffer;
210        private BufferedImage offscreenBuffer;
211        // Layers that wasn't changed since last paint
212        private final List<Layer> nonChangedLayers = new ArrayList<Layer>();
213        private Layer changedLayer;
214        private int lastViewID;
215        private boolean paintPreferencesChanged = true;
216        private Rectangle lastClipBounds = new Rectangle();
217        private MapMover mapMover;
218    
219        /**
220         * Constructs a new {@code MapView}.
221         * @param contentPane The content pane used to register shortcuts in its {@link InputMap} and {@link ActionMap}
222         */
223        public MapView(final JPanel contentPane) {
224            Main.pref.addPreferenceChangeListener(this);
225    
226            addComponentListener(new ComponentAdapter(){
227                @Override public void componentResized(ComponentEvent e) {
228                    removeComponentListener(this);
229    
230                    MapSlider zoomSlider = new MapSlider(MapView.this);
231                    add(zoomSlider);
232                    zoomSlider.setBounds(3, 0, 114, 30);
233    
234                    MapScaler scaler = new MapScaler(MapView.this);
235                    add(scaler);
236                    scaler.setLocation(10,30);
237    
238                    mapMover = new MapMover(MapView.this, contentPane);
239                    OsmDataLayer layer = getEditLayer();
240                    if (layer != null) {
241                        if (!zoomToDataSetBoundingBox(layer.data)) {
242                            // no bounding box defined
243                            AutoScaleAction.autoScale("data");
244                        }
245                    } else {
246                        AutoScaleAction.autoScale("layer");
247                    }
248                }
249            });
250    
251            // listend to selection changes to redraw the map
252            DataSet.addSelectionListener(repaintSelectionChangedListener);
253    
254            //store the last mouse action
255            this.addMouseMotionListener(new MouseMotionListener() {
256                public void mouseDragged(MouseEvent e) {
257                    mouseMoved(e);
258                }
259                public void mouseMoved(MouseEvent e) {
260                    lastMEvent = e;
261                }
262            });
263        }
264    
265        /**
266         * Adds a GPX layer. A GPX layer is added below the lowest data layer.
267         *
268         * @param layer the GPX layer
269         */
270        protected void addGpxLayer(GpxLayer layer) {
271            if (layers.isEmpty()) {
272                layers.add(layer);
273                return;
274            }
275            for (int i=layers.size()-1; i>= 0; i--) {
276                if (layers.get(i) instanceof OsmDataLayer) {
277                    if (i == layers.size()-1) {
278                        layers.add(layer);
279                    } else {
280                        layers.add(i+1, layer);
281                    }
282                    return;
283                }
284            }
285            layers.add(0, layer);
286        }
287    
288        /**
289         * Add a layer to the current MapView. The layer will be added at topmost
290         * position.
291         * @param layer The layer to add
292         */
293        public void addLayer(Layer layer) {
294            if (layer instanceof MarkerLayer && playHeadMarker == null) {
295                playHeadMarker = PlayHeadMarker.create();
296            }
297    
298            if (layer instanceof GpxLayer) {
299                addGpxLayer((GpxLayer)layer);
300            } else if (layers.isEmpty()) {
301                layers.add(layer);
302            } else if (layer.isBackgroundLayer()) {
303                int i = 0;
304                for (; i < layers.size(); i++) {
305                    if (layers.get(i).isBackgroundLayer()) {
306                        break;
307                    }
308                }
309                layers.add(i, layer);
310            } else {
311                layers.add(0, layer);
312            }
313            fireLayerAdded(layer);
314            boolean isOsmDataLayer = layer instanceof OsmDataLayer;
315            if (isOsmDataLayer) {
316                ((OsmDataLayer)layer).addLayerStateChangeListener(this);
317            }
318            boolean callSetActiveLayer = isOsmDataLayer || activeLayer == null;
319            if (callSetActiveLayer) {
320                // autoselect the new layer
321                setActiveLayer(layer); // also repaints this MapView
322            }
323            layer.addPropertyChangeListener(this);
324            Main.addProjectionChangeListener(layer);
325            AudioPlayer.reset();
326            if (!callSetActiveLayer) {
327                repaint();
328            }
329        }
330    
331        @Override
332        protected DataSet getCurrentDataSet() {
333            if (editLayer != null)
334                return editLayer.data;
335            else
336                return null;
337        }
338    
339        /**
340         * Replies true if the active layer is drawable.
341         *
342         * @return true if the active layer is drawable, false otherwise
343         */
344        public boolean isActiveLayerDrawable() {
345            return editLayer != null;
346        }
347    
348        /**
349         * Replies true if the active layer is visible.
350         *
351         * @return true if the active layer is visible, false otherwise
352         */
353        public boolean isActiveLayerVisible() {
354            return isActiveLayerDrawable() && editLayer.isVisible();
355        }
356    
357        /**
358         * Determines the next active data layer according to the following
359         * rules:
360         * <ul>
361         *   <li>if there is at least one {@link OsmDataLayer} the first one
362         *     becomes active</li>
363         *   <li>otherwise, the top most layer of any type becomes active</li>
364         * </ul>
365         *
366         * @return the next active data layer
367         */
368        protected Layer determineNextActiveLayer(List<Layer> layersList) {
369            // First look for data layer
370            for (Layer layer:layersList) {
371                if (layer instanceof OsmDataLayer)
372                    return layer;
373            }
374    
375            // Then any layer
376            if (!layersList.isEmpty())
377                return layersList.get(0);
378    
379            // and then give up
380            return null;
381    
382        }
383    
384        /**
385         * Remove the layer from the mapview. If the layer was in the list before,
386         * an LayerChange event is fired.
387         * @param layer The layer to remove
388         */
389        public void removeLayer(Layer layer) {
390            List<Layer> layersList = new ArrayList<Layer>(layers);
391    
392            if (!layersList.remove(layer))
393                return;
394    
395            setEditLayer(layersList);
396    
397            if (layer == activeLayer) {
398                setActiveLayer(determineNextActiveLayer(layersList), false);
399            }
400            
401            if (layer instanceof OsmDataLayer) {
402                ((OsmDataLayer)layer).removeLayerPropertyChangeListener(this);
403            }
404    
405            layers.remove(layer);
406            Main.removeProjectionChangeListener(layer);
407            fireLayerRemoved(layer);
408            layer.removePropertyChangeListener(this);
409            layer.destroy();
410            AudioPlayer.reset();
411            repaint();
412        }
413    
414        private boolean virtualNodesEnabled = false;
415    
416        public void setVirtualNodesEnabled(boolean enabled) {
417            if(virtualNodesEnabled != enabled) {
418                virtualNodesEnabled = enabled;
419                repaint();
420            }
421        }
422        public boolean isVirtualNodesEnabled() {
423            return virtualNodesEnabled;
424        }
425    
426        /**
427         * Moves the layer to the given new position. No event is fired, but repaints
428         * according to the new Z-Order of the layers.
429         *
430         * @param layer     The layer to move
431         * @param pos       The new position of the layer
432         */
433        public void moveLayer(Layer layer, int pos) {
434            int curLayerPos = layers.indexOf(layer);
435            if (curLayerPos == -1)
436                throw new IllegalArgumentException(tr("Layer not in list."));
437            if (pos == curLayerPos)
438                return; // already in place.
439            layers.remove(curLayerPos);
440            if (pos >= layers.size()) {
441                layers.add(layer);
442            } else {
443                layers.add(pos, layer);
444            }
445            setEditLayer(layers);
446            AudioPlayer.reset();
447            repaint();
448        }
449    
450        public int getLayerPos(Layer layer) {
451            int curLayerPos = layers.indexOf(layer);
452            if (curLayerPos == -1)
453                throw new IllegalArgumentException(tr("Layer not in list."));
454            return curLayerPos;
455        }
456    
457        /**
458         * Creates a list of the visible layers in Z-Order, the layer with the lowest Z-Order
459         * first, layer with the highest Z-Order last.
460         *
461         * @return a list of the visible in Z-Order, the layer with the lowest Z-Order
462         * first, layer with the highest Z-Order last.
463         */
464        protected List<Layer> getVisibleLayersInZOrder() {
465            ArrayList<Layer> ret = new ArrayList<Layer>();
466            for (Layer l: layers) {
467                if (l.isVisible()) {
468                    ret.add(l);
469                }
470            }
471            // sort according to position in the list of layers, with one exception:
472            // an active data layer always becomes a higher Z-Order than all other
473            // data layers
474            //
475            Collections.sort(
476                    ret,
477                    new Comparator<Layer>() {
478                        public int compare(Layer l1, Layer l2) {
479                            if (l1 instanceof OsmDataLayer && l2 instanceof OsmDataLayer) {
480                                if (l1 == getActiveLayer()) return -1;
481                                if (l2 == getActiveLayer()) return 1;
482                                return Integer.valueOf(layers.indexOf(l1)).compareTo(layers.indexOf(l2));
483                            } else
484                                return Integer.valueOf(layers.indexOf(l1)).compareTo(layers.indexOf(l2));
485                        }
486                    }
487            );
488            Collections.reverse(ret);
489            return ret;
490        }
491    
492        private void paintLayer(Layer layer, Graphics2D g, Bounds box) {
493            if (layer.getOpacity() < 1) {
494                g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER,(float)layer.getOpacity()));
495            }
496            layer.paint(g, this, box);
497            g.setPaintMode();
498        }
499    
500        /**
501         * Draw the component.
502         */
503        @Override public void paint(Graphics g) {
504            if (BugReportExceptionHandler.exceptionHandlingInProgress())
505                return;
506    
507            if (center == null)
508                return; // no data loaded yet.
509    
510            List<Layer> visibleLayers = getVisibleLayersInZOrder();
511    
512            int nonChangedLayersCount = 0;
513            for (Layer l: visibleLayers) {
514                if (l.isChanged() || l == changedLayer) {
515                    break;
516                } else {
517                    nonChangedLayersCount++;
518                }
519            }
520    
521            boolean canUseBuffer;
522            
523            synchronized (this) {
524                canUseBuffer = !paintPreferencesChanged;
525                paintPreferencesChanged = false;
526            }
527            canUseBuffer = canUseBuffer && nonChangedLayers.size() <= nonChangedLayersCount &&
528            lastViewID == getViewID() && lastClipBounds.contains(g.getClipBounds());
529            if (canUseBuffer) {
530                for (int i=0; i<nonChangedLayers.size(); i++) {
531                    if (visibleLayers.get(i) != nonChangedLayers.get(i)) {
532                        canUseBuffer = false;
533                        break;
534                    }
535                }
536            }
537    
538            if (null == offscreenBuffer || offscreenBuffer.getWidth() != getWidth() || offscreenBuffer.getHeight() != getHeight()) {
539                offscreenBuffer = new BufferedImage(getWidth(), getHeight(), BufferedImage.TYPE_3BYTE_BGR);
540            }
541    
542            Graphics2D tempG = offscreenBuffer.createGraphics();
543            tempG.setClip(g.getClip());
544            Bounds box = getLatLonBounds(g.getClipBounds());
545    
546            if (!canUseBuffer || nonChangedLayersBuffer == null) {
547                if (null == nonChangedLayersBuffer || nonChangedLayersBuffer.getWidth() != getWidth() || nonChangedLayersBuffer.getHeight() != getHeight()) {
548                    nonChangedLayersBuffer = new BufferedImage(getWidth(), getHeight(), BufferedImage.TYPE_3BYTE_BGR);
549                }
550                Graphics2D g2 = nonChangedLayersBuffer.createGraphics();
551                g2.setClip(g.getClip());
552                g2.setColor(PaintColors.getBackgroundColor());
553                g2.fillRect(0, 0, getWidth(), getHeight());
554    
555                for (int i=0; i<nonChangedLayersCount; i++) {
556                    paintLayer(visibleLayers.get(i),g2, box);
557                }
558            } else {
559                // Maybe there were more unchanged layers then last time - draw them to buffer
560                if (nonChangedLayers.size() != nonChangedLayersCount) {
561                    Graphics2D g2 = nonChangedLayersBuffer.createGraphics();
562                    g2.setClip(g.getClip());
563                    for (int i=nonChangedLayers.size(); i<nonChangedLayersCount; i++) {
564                        paintLayer(visibleLayers.get(i),g2, box);
565                    }
566                }
567            }
568    
569            nonChangedLayers.clear();
570            changedLayer = null;
571            for (int i=0; i<nonChangedLayersCount; i++) {
572                nonChangedLayers.add(visibleLayers.get(i));
573            }
574            lastViewID = getViewID();
575            lastClipBounds = g.getClipBounds();
576    
577            tempG.drawImage(nonChangedLayersBuffer, 0, 0, null);
578    
579            for (int i=nonChangedLayersCount; i<visibleLayers.size(); i++) {
580                paintLayer(visibleLayers.get(i),tempG, box);
581            }
582    
583            for (MapViewPaintable mvp : temporaryLayers) {
584                mvp.paint(tempG, this, box);
585            }
586    
587            // draw world borders
588            tempG.setColor(Color.WHITE);
589            Bounds b = getProjection().getWorldBoundsLatLon();
590            double lat = b.getMin().lat();
591            double lon = b.getMin().lon();
592    
593            Point p = getPoint(b.getMin());
594    
595            GeneralPath path = new GeneralPath();
596    
597            path.moveTo(p.x, p.y);
598            double max = b.getMax().lat();
599            for(; lat <= max; lat += 1.0)
600            {
601                p = getPoint(new LatLon(lat >= max ? max : lat, lon));
602                path.lineTo(p.x, p.y);
603            }
604            lat = max; max = b.getMax().lon();
605            for(; lon <= max; lon += 1.0)
606            {
607                p = getPoint(new LatLon(lat, lon >= max ? max : lon));
608                path.lineTo(p.x, p.y);
609            }
610            lon = max; max = b.getMin().lat();
611            for(; lat >= max; lat -= 1.0)
612            {
613                p = getPoint(new LatLon(lat <= max ? max : lat, lon));
614                path.lineTo(p.x, p.y);
615            }
616            lat = max; max = b.getMin().lon();
617            for(; lon >= max; lon -= 1.0)
618            {
619                p = getPoint(new LatLon(lat, lon <= max ? max : lon));
620                path.lineTo(p.x, p.y);
621            }
622    
623            int w = getWidth();
624            int h = getHeight();
625    
626            // Work around OpenJDK having problems when drawing out of bounds
627            final Area border = new Area(path);
628            // Make the viewport 1px larger in every direction to prevent an
629            // additional 1px border when zooming in
630            final Area viewport = new Area(new Rectangle(-1, -1, w + 2, h + 2));
631            border.intersect(viewport);
632            tempG.draw(border);
633    
634            if (Main.isDisplayingMapView() && Main.map.filterDialog != null) {
635                Main.map.filterDialog.drawOSDText(tempG);
636            }
637    
638            if (playHeadMarker != null) {
639                playHeadMarker.paint(tempG, this);
640            }
641    
642            g.drawImage(offscreenBuffer, 0, 0, null);
643            super.paint(g);
644        }
645    
646        /**
647         * Set the new dimension to the view.
648         */
649        public void recalculateCenterScale(BoundingXYVisitor box) {
650            if (box == null) {
651                box = new BoundingXYVisitor();
652            }
653            if (box.getBounds() == null) {
654                box.visit(getProjection().getWorldBoundsLatLon());
655            }
656            if (!box.hasExtend()) {
657                box.enlargeBoundingBox();
658            }
659    
660            zoomTo(box.getBounds());
661        }
662    
663        /**
664         * @return An unmodifiable collection of all layers
665         */
666        public Collection<Layer> getAllLayers() {
667            return Collections.unmodifiableCollection(layers);
668        }
669    
670        /**
671         * @return An unmodifiable ordered list of all layers
672         */
673        public List<Layer> getAllLayersAsList() {
674            return Collections.unmodifiableList(layers);
675        }
676    
677        /**
678         * Replies an unmodifiable list of layers of a certain type.
679         *
680         * Example:
681         * <pre>
682         *     List<WMSLayer> wmsLayers = getLayersOfType(WMSLayer.class);
683         * </pre>
684         *
685         * @return an unmodifiable list of layers of a certain type.
686         */
687        public <T> List<T>  getLayersOfType(Class<T> ofType) {
688            ArrayList<T> ret = new ArrayList<T>();
689            for (Layer layer : getAllLayersAsList()) {
690                if (ofType.isInstance(layer)) {
691                    ret.add(ofType.cast(layer));
692                }
693            }
694            return ret;
695        }
696    
697        /**
698         * Replies the number of layers managed by this mav view
699         *
700         * @return the number of layers managed by this mav view
701         */
702        public int getNumLayers() {
703            return layers.size();
704        }
705    
706        /**
707         * Replies true if there is at least one layer in this map view
708         *
709         * @return true if there is at least one layer in this map view
710         */
711        public boolean hasLayers() {
712            return getNumLayers() > 0;
713        }
714    
715        private void setEditLayer(List<Layer> layersList) {
716            OsmDataLayer newEditLayer = layersList.contains(editLayer)?editLayer:null;
717            OsmDataLayer oldEditLayer = editLayer;
718    
719            // Find new edit layer
720            if (activeLayer != editLayer || !layersList.contains(editLayer)) {
721                if (activeLayer instanceof OsmDataLayer && layersList.contains(activeLayer)) {
722                    newEditLayer = (OsmDataLayer) activeLayer;
723                } else {
724                    for (Layer layer:layersList) {
725                        if (layer instanceof OsmDataLayer) {
726                            newEditLayer = (OsmDataLayer) layer;
727                            break;
728                        }
729                    }
730                }
731            }
732    
733            // Set new edit layer
734            if (newEditLayer != editLayer) {
735                if (newEditLayer == null) {
736                    getCurrentDataSet().setSelected();
737                }
738    
739                editLayer = newEditLayer;
740                fireEditLayerChanged(oldEditLayer, newEditLayer);
741                refreshTitle();
742            }
743    
744        }
745    
746        /**
747         * Sets the active layer to <code>layer</code>. If <code>layer</code> is an instance
748         * of {@link OsmDataLayer} also sets {@link #editLayer} to <code>layer</code>.
749         *
750         * @param layer the layer to be activate; must be one of the layers in the list of layers
751         * @exception IllegalArgumentException thrown if layer is not in the lis of layers
752         */
753        public void setActiveLayer(Layer layer) {
754            setActiveLayer(layer, true);
755        }
756    
757        private void setActiveLayer(Layer layer, boolean setEditLayer) {
758            if (layer != null && !layers.contains(layer))
759                throw new IllegalArgumentException(tr("Layer ''{0}'' must be in list of layers", layer.toString()));
760    
761            if (layer == activeLayer)
762                return;
763    
764            Layer old = activeLayer;
765            activeLayer = layer;
766            if (setEditLayer) {
767                setEditLayer(layers);
768            }
769            fireActiveLayerChanged(old, layer);
770    
771            /* This only makes the buttons look disabled. Disabling the actions as well requires
772             * the user to re-select the tool after i.e. moving a layer. While testing I found
773             * that I switch layers and actions at the same time and it was annoying to mind the
774             * order. This way it works as visual clue for new users */
775            for (Enumeration<AbstractButton> e = Main.map.toolGroup.getElements() ; e.hasMoreElements() ;) {
776                AbstractButton button = e.nextElement();
777                MapMode mode = (MapMode)button.getAction();
778                boolean isLayerSupported = mode.layerIsSupported(layer);
779                button.setEnabled(isLayerSupported);
780                // Also update associated shortcut (fix #6876)
781                if (isLayerSupported) {
782                    Main.registerActionShortcut(mode, mode.getShortcut());
783                } else {
784                    Main.unregisterShortcut(mode.getShortcut());
785                }
786            }
787            AudioPlayer.reset();
788            repaint();
789        }
790    
791        /**
792         * Replies the currently active layer
793         *
794         * @return the currently active layer (may be null)
795         */
796        public Layer getActiveLayer() {
797            return activeLayer;
798        }
799    
800        /**
801         * Replies the current edit layer, if any
802         *
803         * @return the current edit layer. May be null.
804         */
805        public OsmDataLayer getEditLayer() {
806            return editLayer;
807        }
808    
809        /**
810         * replies true if the list of layers managed by this map view contain layer
811         *
812         * @param layer the layer
813         * @return true if the list of layers managed by this map view contain layer
814         */
815        public boolean hasLayer(Layer layer) {
816            return layers.contains(layer);
817        }
818    
819        /**
820         * Tries to zoom to the download boundingbox[es] of the current edit layer
821         * (aka {@link OsmDataLayer}). If the edit layer has multiple download bounding
822         * boxes it zooms to a large virtual bounding box containing all smaller ones.
823         *
824         * @return <code>true</code> if a zoom operation has been performed
825         */
826        public boolean zoomToDataSetBoundingBox(DataSet ds) {
827            // In case we already have an existing data layer ...
828            OsmDataLayer layer= getEditLayer();
829            if (layer == null)
830                return false;
831            Collection<DataSource> dataSources = ds.dataSources;
832            // ... with bounding box[es] of data loaded from OSM or a file...
833            BoundingXYVisitor bbox = new BoundingXYVisitor();
834            for (DataSource source : dataSources) {
835                bbox.visit(source.bounds);
836            }
837            if (bbox.hasExtend()) {
838                // ... we zoom to it's bounding box
839                recalculateCenterScale(bbox);
840                return true;
841            }
842            return false;
843        }
844    
845        public boolean addTemporaryLayer(MapViewPaintable mvp) {
846            if (temporaryLayers.contains(mvp)) return false;
847            return temporaryLayers.add(mvp);
848        }
849    
850        public boolean removeTemporaryLayer(MapViewPaintable mvp) {
851            return temporaryLayers.remove(mvp);
852        }
853    
854        public void propertyChange(PropertyChangeEvent evt) {
855            if (evt.getPropertyName().equals(Layer.VISIBLE_PROP)) {
856                repaint();
857            } else if (evt.getPropertyName().equals(Layer.OPACITY_PROP)) {
858                Layer l = (Layer)evt.getSource();
859                if (l.isVisible()) {
860                    changedLayer = l;
861                    repaint();
862                }
863            } else if (evt.getPropertyName().equals(OsmDataLayer.REQUIRES_SAVE_TO_DISK_PROP)
864                    || evt.getPropertyName().equals(OsmDataLayer.REQUIRES_UPLOAD_TO_SERVER_PROP)) {
865                OsmDataLayer layer = (OsmDataLayer)evt.getSource();
866                if (layer == getEditLayer()) {
867                    refreshTitle();
868                }
869            }
870        }
871    
872        protected void refreshTitle() {
873            boolean dirty = editLayer != null && (editLayer.requiresSaveToFile() || (editLayer.requiresUploadToServer() && !editLayer.isUploadDiscouraged()));
874            if (dirty) {
875                JOptionPane.getFrameForComponent(Main.parent).setTitle("* " + tr("Java OpenStreetMap Editor"));
876            } else {
877                JOptionPane.getFrameForComponent(Main.parent).setTitle(tr("Java OpenStreetMap Editor"));
878            }
879        }
880    
881        @Override
882        public void preferenceChanged(PreferenceChangeEvent e) {
883            synchronized (this) {
884                paintPreferencesChanged = true;
885            }
886        }
887    
888        private SelectionChangedListener repaintSelectionChangedListener = new SelectionChangedListener(){
889            public void selectionChanged(Collection<? extends OsmPrimitive> newSelection) {
890                repaint();
891            }
892        };
893    
894        public void destroy() {
895            Main.pref.removePreferenceChangeListener(this);
896            DataSet.removeSelectionListener(repaintSelectionChangedListener);
897            MultipolygonCache.getInstance().clear(this);
898            if (mapMover != null) {
899                mapMover.destroy();
900            }
901        }
902    
903        @Override
904        public void uploadDiscouragedChanged(OsmDataLayer layer, boolean newValue) {
905            if (layer == getEditLayer()) {
906                refreshTitle();
907            }
908        }
909    }