001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.gui.widgets;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.awt.event.ActionEvent;
007import java.awt.event.ActionListener;
008import java.awt.event.ItemListener;
009import java.awt.event.MouseAdapter;
010import java.awt.event.MouseEvent;
011import java.awt.event.MouseListener;
012
013import javax.swing.AbstractAction;
014import javax.swing.ActionMap;
015import javax.swing.ButtonGroup;
016import javax.swing.ButtonModel;
017import javax.swing.Icon;
018import javax.swing.JCheckBox;
019import javax.swing.SwingUtilities;
020import javax.swing.event.ChangeListener;
021import javax.swing.plaf.ActionMapUIResource;
022
023import org.openstreetmap.josm.tools.Utils;
024
025/**
026 * A four-state checkbox. The states are enumerated in {@link State}.
027 * @since 591
028 */
029public class QuadStateCheckBox extends JCheckBox {
030
031    /**
032     * The 4 possible states of this checkbox.
033     */
034    public enum State {
035        /** Not selected: the property is explicitly switched off */
036        NOT_SELECTED,
037        /** Selected: the property is explicitly switched on */
038        SELECTED,
039        /** Unset: do not set this property on the selected objects */
040        UNSET,
041        /** Partial: different selected objects have different values, do not change */
042        PARTIAL
043    }
044
045    private final QuadStateDecorator model;
046    private State[] allowed;
047
048    /**
049     * Constructs a new {@code QuadStateCheckBox}.
050     * @param text the text of the check box
051     * @param icon the Icon image to display
052     * @param initial The initial state
053     * @param allowed The allowed states
054     */
055    public QuadStateCheckBox(String text, Icon icon, State initial, State[] allowed) {
056        super(text, icon);
057        this.allowed = Utils.copyArray(allowed);
058        // Add a listener for when the mouse is pressed
059        super.addMouseListener(new MouseAdapter() {
060            @Override public void mousePressed(MouseEvent e) {
061                grabFocus();
062                model.nextState();
063            }
064        });
065        // Reset the keyboard action map
066        ActionMap map = new ActionMapUIResource();
067        map.put("pressed", new AbstractAction() {
068            @Override
069            public void actionPerformed(ActionEvent e) {
070                grabFocus();
071                model.nextState();
072            }
073        });
074        map.put("released", null);
075        SwingUtilities.replaceUIActionMap(this, map);
076        // set the model to the adapted model
077        model = new QuadStateDecorator(getModel());
078        setModel(model);
079        setState(initial);
080    }
081    
082    /**
083     * Constructs a new {@code QuadStateCheckBox}.
084     * @param text the text of the check box
085     * @param initial The initial state
086     * @param allowed The allowed states
087     */
088    public QuadStateCheckBox(String text, State initial, State[] allowed) {
089        this(text, null, initial, allowed);
090    }
091
092    /** Do not let anyone add mouse listeners */
093    @Override public void addMouseListener(MouseListener l) { }
094    
095    /**
096     * Set the new state.
097     * @param state The new state
098     */
099    public void setState(State state) {
100        model.setState(state);
101    }
102    
103    /** 
104     * Return the current state, which is determined by the selection status of the model. 
105     * @return The current state 
106     */
107    public State getState() {
108        return model.getState();
109    }
110    
111    @Override
112    public void setSelected(boolean b) {
113        if (b) {
114            setState(State.SELECTED);
115        } else {
116            setState(State.NOT_SELECTED);
117        }
118    }
119
120    private final class QuadStateDecorator implements ButtonModel {
121        private final ButtonModel other;
122        
123        private QuadStateDecorator(ButtonModel other) {
124            this.other = other;
125        }
126        
127        private void setState(State state) {
128            if (state == State.NOT_SELECTED) {
129                other.setArmed(false);
130                other.setPressed(false);
131                other.setSelected(false);
132                setToolTipText(tr("false: the property is explicitly switched off"));
133            } else if (state == State.SELECTED) {
134                other.setArmed(false);
135                other.setPressed(false);
136                other.setSelected(true);
137                setToolTipText(tr("true: the property is explicitly switched on"));
138            } else if (state == State.PARTIAL) {
139                other.setArmed(true);
140                other.setPressed(true);
141                other.setSelected(true);
142                setToolTipText(tr("partial: different selected objects have different values, do not change"));
143            } else {
144                other.setArmed(true);
145                other.setPressed(true);
146                other.setSelected(false);
147                setToolTipText(tr("unset: do not set this property on the selected objects"));
148            }
149        }
150        
151        /**
152         * The current state is embedded in the selection / armed
153         * state of the model.
154         *
155         * We return the SELECTED state when the checkbox is selected
156         * but not armed, PARTIAL state when the checkbox is
157         * selected and armed (grey) and NOT_SELECTED when the
158         * checkbox is deselected.
159         */
160        private State getState() {
161            if (isSelected() && !isArmed()) {
162                // normal black tick
163                return State.SELECTED;
164            } else if (isSelected() && isArmed()) {
165                // don't care grey tick
166                return State.PARTIAL;
167            } else if (!isSelected() && !isArmed()) {
168                return State.NOT_SELECTED;
169            } else {
170                return State.UNSET;
171            }
172        }
173        /** Rotate to the next allowed state.*/
174        private void nextState() {
175            State current = getState();
176            for (int i = 0; i < allowed.length; i++) {
177                if (allowed[i] == current) {
178                    setState((i == allowed.length-1) ? allowed[0] : allowed[i+1]);
179                    break;
180                }
181            }
182        }
183        /** Filter: No one may change the armed/selected/pressed status except us. */
184        @Override public void setArmed(boolean b) { }
185        @Override public void setSelected(boolean b) { }
186        @Override public void setPressed(boolean b) { }
187        /** We disable focusing on the component when it is not enabled. */
188        @Override public void setEnabled(boolean b) {
189            setFocusable(b);
190            other.setEnabled(b);
191        }
192        /** All these methods simply delegate to the "other" model
193         * that is being decorated. */
194        @Override public boolean isArmed() { return other.isArmed(); }
195        @Override public boolean isSelected() { return other.isSelected(); }
196        @Override public boolean isEnabled() { return other.isEnabled(); }
197        @Override public boolean isPressed() { return other.isPressed(); }
198        @Override public boolean isRollover() { return other.isRollover(); }
199        @Override public void setRollover(boolean b) { other.setRollover(b); }
200        @Override public void setMnemonic(int key) { other.setMnemonic(key); }
201        @Override public int getMnemonic() { return other.getMnemonic(); }
202        @Override public void setActionCommand(String s) {
203            other.setActionCommand(s);
204        }
205        @Override public String getActionCommand() {
206            return other.getActionCommand();
207        }
208        @Override public void setGroup(ButtonGroup group) {
209            other.setGroup(group);
210        }
211        @Override public void addActionListener(ActionListener l) {
212            other.addActionListener(l);
213        }
214        @Override public void removeActionListener(ActionListener l) {
215            other.removeActionListener(l);
216        }
217        @Override public void addItemListener(ItemListener l) {
218            other.addItemListener(l);
219        }
220        @Override public void removeItemListener(ItemListener l) {
221            other.removeItemListener(l);
222        }
223        @Override public void addChangeListener(ChangeListener l) {
224            other.addChangeListener(l);
225        }
226        @Override public void removeChangeListener(ChangeListener l) {
227            other.removeChangeListener(l);
228        }
229        @Override public Object[] getSelectedObjects() {
230            return other.getSelectedObjects();
231        }
232    }
233}