001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.actions;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.awt.event.KeyEvent;
007import java.util.Collection;
008
009import javax.swing.AbstractAction;
010
011import org.openstreetmap.josm.Main;
012import org.openstreetmap.josm.data.SelectionChangedListener;
013import org.openstreetmap.josm.data.osm.DataSet;
014import org.openstreetmap.josm.data.osm.OsmPrimitive;
015import org.openstreetmap.josm.gui.MapView;
016import org.openstreetmap.josm.gui.MapView.LayerChangeListener;
017import org.openstreetmap.josm.gui.layer.Layer;
018import org.openstreetmap.josm.gui.layer.OsmDataLayer;
019import org.openstreetmap.josm.gui.util.GuiHelper;
020import org.openstreetmap.josm.tools.Destroyable;
021import org.openstreetmap.josm.tools.ImageProvider;
022import org.openstreetmap.josm.tools.Shortcut;
023
024/**
025 * Base class helper for all Actions in JOSM. Just to make the life easier.
026 *
027 * A JosmAction is a {@link LayerChangeListener} and a {@link SelectionChangedListener}. Upon
028 * a layer change event or a selection change event it invokes {@link #updateEnabledState()}.
029 * Subclasses can override {@link #updateEnabledState()} in order to update the {@link #isEnabled()}-state
030 * of a JosmAction depending on the {@link #getCurrentDataSet()} and the current layers
031 * (see also {@link #getEditLayer()}).
032 *
033 * destroy() from interface Destroyable is called e.g. for MapModes, when the last layer has
034 * been removed and so the mapframe will be destroyed. For other JosmActions, destroy() may never
035 * be called (currently).
036 *
037 * @author imi
038 */
039public abstract class JosmAction extends AbstractAction implements Destroyable {
040
041    protected transient Shortcut sc;
042    private transient LayerChangeAdapter layerChangeAdapter;
043    private transient SelectionChangeAdapter selectionChangeAdapter;
044
045    /**
046     * Returns the shortcut for this action.
047     * @return the shortcut for this action, or "No shortcut" if none is defined
048     */
049    public Shortcut getShortcut() {
050        if (sc == null) {
051            sc = Shortcut.registerShortcut("core:none", tr("No Shortcut"), KeyEvent.CHAR_UNDEFINED, Shortcut.NONE);
052            // as this shortcut is shared by all action that don't want to have a shortcut,
053            // we shouldn't allow the user to change it...
054            // this is handled by special name "core:none"
055        }
056        return sc;
057    }
058
059    /**
060     * Constructs a {@code JosmAction}.
061     *
062     * @param name the action's text as displayed on the menu (if it is added to a menu)
063     * @param icon the icon to use
064     * @param tooltip  a longer description of the action that will be displayed in the tooltip. Please note
065     *           that html is not supported for menu actions on some platforms.
066     * @param shortcut a ready-created shortcut object or null if you don't want a shortcut. But you always
067     *            do want a shortcut, remember you can always register it with group=none, so you
068     *            won't be assigned a shortcut unless the user configures one. If you pass null here,
069     *            the user CANNOT configure a shortcut for your action.
070     * @param registerInToolbar register this action for the toolbar preferences?
071     * @param toolbarId identifier for the toolbar preferences. The iconName is used, if this parameter is null
072     * @param installAdapters false, if you don't want to install layer changed and selection changed adapters
073     * TODO: do not pass Icon, pass ImageProvider instead
074     */
075    public JosmAction(String name, ImageProvider icon, String tooltip, Shortcut shortcut, boolean registerInToolbar,
076            String toolbarId, boolean installAdapters) {
077        super(name);
078        if (icon != null)
079            icon.getResource().getImageIcon(this);
080        setHelpId();
081        sc = shortcut;
082        if (sc != null) {
083            Main.registerActionShortcut(this, sc);
084        }
085        setTooltip(tooltip);
086        if (getValue("toolbar") == null) {
087            putValue("toolbar", toolbarId);
088        }
089        if (registerInToolbar && Main.toolbar != null) {
090            Main.toolbar.register(this);
091        }
092        if (installAdapters) {
093            installAdapters();
094        }
095    }
096
097    /**
098     * The new super for all actions.
099     *
100     * Use this super constructor to setup your action.
101     *
102     * @param name the action's text as displayed on the menu (if it is added to a menu)
103     * @param iconName the filename of the icon to use
104     * @param tooltip  a longer description of the action that will be displayed in the tooltip. Please note
105     *           that html is not supported for menu actions on some platforms.
106     * @param shortcut a ready-created shortcut object or null if you don't want a shortcut. But you always
107     *            do want a shortcut, remember you can always register it with group=none, so you
108     *            won't be assigned a shortcut unless the user configures one. If you pass null here,
109     *            the user CANNOT configure a shortcut for your action.
110     * @param registerInToolbar register this action for the toolbar preferences?
111     * @param toolbarId identifier for the toolbar preferences. The iconName is used, if this parameter is null
112     * @param installAdapters false, if you don't want to install layer changed and selection changed adapters
113     */
114    public JosmAction(String name, String iconName, String tooltip, Shortcut shortcut, boolean registerInToolbar,
115            String toolbarId, boolean installAdapters) {
116        this(name, iconName == null ? null : new ImageProvider(iconName), tooltip, shortcut, registerInToolbar,
117                toolbarId == null ? iconName : toolbarId, installAdapters);
118    }
119
120    /**
121     * Constructs a new {@code JosmAction}.
122     *
123     * Use this super constructor to setup your action.
124     *
125     * @param name the action's text as displayed on the menu (if it is added to a menu)
126     * @param iconName the filename of the icon to use
127     * @param tooltip  a longer description of the action that will be displayed in the tooltip. Please note
128     *           that html is not supported for menu actions on some platforms.
129     * @param shortcut a ready-created shortcut object or null if you don't want a shortcut. But you always
130     *            do want a shortcut, remember you can always register it with group=none, so you
131     *            won't be assigned a shortcut unless the user configures one. If you pass null here,
132     *            the user CANNOT configure a shortcut for your action.
133     * @param registerInToolbar register this action for the toolbar preferences?
134     * @param installAdapters false, if you don't want to install layer changed and selection changed adapters
135     */
136    public JosmAction(String name, String iconName, String tooltip, Shortcut shortcut, boolean registerInToolbar, boolean installAdapters) {
137        this(name, iconName, tooltip, shortcut, registerInToolbar, null, installAdapters);
138    }
139
140    /**
141     * Constructs a new {@code JosmAction}.
142     *
143     * Use this super constructor to setup your action.
144     *
145     * @param name the action's text as displayed on the menu (if it is added to a menu)
146     * @param iconName the filename of the icon to use
147     * @param tooltip  a longer description of the action that will be displayed in the tooltip. Please note
148     *           that html is not supported for menu actions on some platforms.
149     * @param shortcut a ready-created shortcut object or null if you don't want a shortcut. But you always
150     *            do want a shortcut, remember you can always register it with group=none, so you
151     *            won't be assigned a shortcut unless the user configures one. If you pass null here,
152     *            the user CANNOT configure a shortcut for your action.
153     * @param registerInToolbar register this action for the toolbar preferences?
154     */
155    public JosmAction(String name, String iconName, String tooltip, Shortcut shortcut, boolean registerInToolbar) {
156        this(name, iconName, tooltip, shortcut, registerInToolbar, null, true);
157    }
158
159    /**
160     * Constructs a new {@code JosmAction}.
161     */
162    public JosmAction() {
163        this(true);
164    }
165
166    /**
167     * Constructs a new {@code JosmAction}.
168     *
169     * @param installAdapters false, if you don't want to install layer changed and selection changed adapters
170     */
171    public JosmAction(boolean installAdapters) {
172        setHelpId();
173        if (installAdapters) {
174            installAdapters();
175        }
176    }
177
178    @Override
179    public void destroy() {
180        if (sc != null) {
181            Main.unregisterActionShortcut(this);
182        }
183        MapView.removeLayerChangeListener(layerChangeAdapter);
184        DataSet.removeSelectionListener(selectionChangeAdapter);
185    }
186
187    private void setHelpId() {
188        String helpId = "Action/"+getClass().getName().substring(getClass().getName().lastIndexOf('.')+1);
189        if (helpId.endsWith("Action")) {
190            helpId = helpId.substring(0, helpId.length()-6);
191        }
192        putValue("help", helpId);
193    }
194
195    /**
196     * Sets the tooltip text of this action.
197     * @param tooltip The text to display in tooltip. Can be {@code null}
198     */
199    public final void setTooltip(String tooltip) {
200        if (tooltip != null) {
201            putValue(SHORT_DESCRIPTION, Main.platform.makeTooltip(tooltip, sc));
202        }
203    }
204
205    /**
206     * Replies the current edit layer
207     *
208     * @return the current edit layer. null, if no edit layer exists
209     */
210    public static OsmDataLayer getEditLayer() {
211        return Main.main != null ? Main.main.getEditLayer() : null;
212    }
213
214    /**
215     * Replies the current dataset.
216     *
217     * @return the current dataset. null, if no current dataset exists
218     */
219    public static DataSet getCurrentDataSet() {
220        return Main.main != null ? Main.main.getCurrentDataSet() : null;
221    }
222
223    protected void installAdapters() {
224        // make this action listen to layer change and selection change events
225        //
226        layerChangeAdapter = new LayerChangeAdapter();
227        selectionChangeAdapter = new SelectionChangeAdapter();
228        MapView.addLayerChangeListener(layerChangeAdapter);
229        DataSet.addSelectionListener(selectionChangeAdapter);
230        initEnabledState();
231    }
232
233    /**
234     * Override in subclasses to init the enabled state of an action when it is
235     * created. Default behaviour is to call {@link #updateEnabledState()}
236     *
237     * @see #updateEnabledState()
238     * @see #updateEnabledState(Collection)
239     */
240    protected void initEnabledState() {
241        updateEnabledState();
242    }
243
244    /**
245     * Override in subclasses to update the enabled state of the action when
246     * something in the JOSM state changes, i.e. when a layer is removed or added.
247     *
248     * See {@link #updateEnabledState(Collection)} to respond to changes in the collection
249     * of selected primitives.
250     *
251     * Default behavior is empty.
252     *
253     * @see #updateEnabledState(Collection)
254     * @see #initEnabledState()
255     */
256    protected void updateEnabledState() {
257    }
258
259    /**
260     * Override in subclasses to update the enabled state of the action if the
261     * collection of selected primitives changes. This method is called with the
262     * new selection.
263     *
264     * @param selection the collection of selected primitives; may be empty, but not null
265     *
266     * @see #updateEnabledState()
267     * @see #initEnabledState()
268     */
269    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
270    }
271
272    /**
273     * Adapter for layer change events
274     *
275     */
276    protected class LayerChangeAdapter implements MapView.LayerChangeListener {
277        private void updateEnabledStateInEDT() {
278            GuiHelper.runInEDT(new Runnable() {
279                @Override public void run() {
280                    updateEnabledState();
281                }
282            });
283        }
284
285        @Override
286        public void activeLayerChange(Layer oldLayer, Layer newLayer) {
287            updateEnabledStateInEDT();
288        }
289
290        @Override
291        public void layerAdded(Layer newLayer) {
292            updateEnabledStateInEDT();
293        }
294
295        @Override
296        public void layerRemoved(Layer oldLayer) {
297            updateEnabledStateInEDT();
298        }
299    }
300
301    /**
302     * Adapter for selection change events
303     */
304    protected class SelectionChangeAdapter implements SelectionChangedListener {
305        @Override
306        public void selectionChanged(Collection<? extends OsmPrimitive> newSelection) {
307            updateEnabledState(newSelection);
308        }
309    }
310}