001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.gui.preferences.display;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.awt.Component;
007import java.util.ArrayList;
008import java.util.Arrays;
009import java.util.List;
010import java.util.Locale;
011
012import javax.swing.Box;
013import javax.swing.DefaultComboBoxModel;
014import javax.swing.DefaultListCellRenderer;
015import javax.swing.JLabel;
016import javax.swing.JList;
017import javax.swing.JPanel;
018import javax.swing.ListCellRenderer;
019
020import org.openstreetmap.josm.Main;
021import org.openstreetmap.josm.gui.preferences.PreferenceSetting;
022import org.openstreetmap.josm.gui.preferences.PreferenceSettingFactory;
023import org.openstreetmap.josm.gui.preferences.PreferenceTabbedPane;
024import org.openstreetmap.josm.gui.preferences.SubPreferenceSetting;
025import org.openstreetmap.josm.gui.preferences.TabPreferenceSetting;
026import org.openstreetmap.josm.gui.widgets.JosmComboBox;
027import org.openstreetmap.josm.tools.GBC;
028import org.openstreetmap.josm.tools.I18n;
029import org.openstreetmap.josm.tools.LanguageInfo;
030
031/**
032 * Language preferences.
033 * @since 1065
034 */
035public class LanguagePreference implements SubPreferenceSetting {
036
037    private static final String LANGUAGE = "language";
038
039    /**
040     * Factory used to create a new {@code LanguagePreference}.
041     */
042    public static class Factory implements PreferenceSettingFactory {
043        @Override
044        public PreferenceSetting createPreferenceSetting() {
045            return new LanguagePreference();
046        }
047    }
048
049    /** the combo box with the available locales */
050    private JosmComboBox<Locale> langCombo;
051
052    @Override
053    public void addGui(final PreferenceTabbedPane gui) {
054        LanguageComboBoxModel model = new LanguageComboBoxModel();
055        // Selecting the language BEFORE the JComboBox listens to model changes speed up initialization by ~35ms (see #7386)
056        // See https://stackoverflow.com/questions/3194958/fast-replacement-for-jcombobox-basiccomboboxui
057        model.selectLanguage(Main.pref.get(LANGUAGE));
058        langCombo = new JosmComboBox<>(model);
059        langCombo.setRenderer(new LanguageCellRenderer());
060
061        LafPreference lafPreference = gui.getSetting(LafPreference.class);
062        final JPanel panel = lafPreference.panel;
063        panel.add(new JLabel(tr("Language")), GBC.std().insets(20, 0, 0, 0));
064        panel.add(GBC.glue(5, 0), GBC.std().fill(GBC.HORIZONTAL));
065        panel.add(langCombo, GBC.eol().fill(GBC.HORIZONTAL));
066        panel.add(Box.createVerticalGlue(), GBC.eol().fill(GBC.BOTH));
067
068        TabPreferenceSetting tabPref = lafPreference.getTabPreferenceSetting(gui);
069        tabPref.registerSubTab(this, tabPref.getSubTab(lafPreference));
070    }
071
072    @Override
073    public boolean ok() {
074        if (langCombo.getSelectedItem() == null)
075            return Main.pref.put(LANGUAGE, null);
076        else
077            return Main.pref.put(LANGUAGE,
078                    LanguageInfo.getJOSMLocaleCode((Locale) langCombo.getSelectedItem()));
079    }
080
081    private static class LanguageComboBoxModel extends DefaultComboBoxModel<Locale> {
082        private final List<Locale> data = new ArrayList<>();
083
084        LanguageComboBoxModel() {
085            data.add(0, null);
086            data.addAll(Arrays.asList(I18n.getAvailableTranslations()));
087        }
088
089        private void selectLanguage(String language) {
090            setSelectedItem(null);
091            if (language != null) {
092                String lang = LanguageInfo.getJavaLocaleCode(language);
093                for (Locale locale: data) {
094                    if (locale == null) {
095                        continue;
096                    }
097                    if (locale.toString().equals(lang)) {
098                        setSelectedItem(locale);
099                        return;
100                    }
101                }
102            }
103        }
104
105        @Override
106        public Locale getElementAt(int index) {
107            return data.get(index);
108        }
109
110        @Override
111        public int getSize() {
112            return data.size();
113        }
114    }
115
116    private static class LanguageCellRenderer implements ListCellRenderer<Locale> {
117        private final DefaultListCellRenderer dispatch;
118
119        /**
120         * Constructs a new {@code LanguageCellRenderer}.
121         */
122        LanguageCellRenderer() {
123            this.dispatch = new DefaultListCellRenderer();
124        }
125
126        @Override
127        public Component getListCellRendererComponent(JList<? extends Locale> list, Locale l,
128                int index, boolean isSelected, boolean cellHasFocus) {
129            return dispatch.getListCellRendererComponent(list,
130                    l == null
131                            ? tr("Default (Auto determined)")
132                            : LanguageInfo.getDisplayName(l),
133                    index, isSelected, cellHasFocus);
134        }
135    }
136
137    @Override
138    public boolean isExpert() {
139        return false;
140    }
141
142    @Override
143    public TabPreferenceSetting getTabPreferenceSetting(final PreferenceTabbedPane gui) {
144        return gui.getSetting(LafPreference.class).getTabPreferenceSetting(gui);
145    }
146}