view/classic/NewMidiInstrumentWizard.java

/*
 *   JSampler - a java front-end for LinuxSampler
 *
 *   Copyright (C) 2005-2007 Grigor Iliev <grigor@grigoriliev.com>
 *
 *   This file is part of JSampler.
 *
 *   JSampler is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License version 2
 *   as published by the Free Software Foundation.
 *
 *   JSampler is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with JSampler; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *   MA  02111-1307  USA
 */

package org.jsampler.view.classic;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFileChooser;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JSlider;
import javax.swing.JSpinner;
import javax.swing.JTextField;
import javax.swing.SpinnerNumberModel;

import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;

import net.sf.juife.Wizard;

import net.sf.juife.wizard.DefaultWizardModel;
import net.sf.juife.wizard.UserInputPage;
import net.sf.juife.wizard.WizardPage;

import org.jsampler.CC;
import org.jsampler.Instrument;
import org.jsampler.MidiInstrumentMap;
import org.jsampler.OrchestraModel;

import org.linuxsampler.lscp.MidiInstrumentInfo;
import org.linuxsampler.lscp.SamplerEngine;

import static org.jsampler.view.classic.ClassicI18n.i18n;


/**
 * A wizard for mapping new MIDI instrument.
 * @author Grigor Iliev
 */
public class NewMidiInstrumentWizard extends Wizard {
        
        /** Creates a new instance of <code>NewMidiInstrumentWizard</code>. */
        public
        NewMidiInstrumentWizard() {
                super(CC.getMainFrame(), i18n.getLabel("NewMidiInstrumentWizard.title"));
                setModel(new NewMidiInstrumentWizardModel());
        }
        
}

class NewMidiInstrumentWizardModel extends DefaultWizardModel {
        private final InstrLocationMethodWizardPage instrLocationMethodWizardPage =
                new InstrLocationMethodWizardPage();
        
        private final OrchestraSelectWizardPage orchestraSelectWizardPage =
                new OrchestraSelectWizardPage();
        
        private final ManualSelectWizardPage manualSelectWizardPage = new ManualSelectWizardPage();
        
        private final InstrumentMappingWizardPage instrumentMappingWizardPage =
                new InstrumentMappingWizardPage();
        
        NewMidiInstrumentWizardModel() {
                addPage(instrLocationMethodWizardPage);
                addStep(i18n.getLabel("NewMidiInstrumentWizard.step1"));
                
                addPage(manualSelectWizardPage);
                addPage(orchestraSelectWizardPage);
                addStep(i18n.getLabel("NewMidiInstrumentWizard.step2"), 2);
                
                addPage(instrumentMappingWizardPage);
                addStep(i18n.getLabel("NewMidiInstrumentWizard.step3"));
        }
        
                /**
         * Moves to the next page in the wizard.
         * @return The next page in the wizard.
         */
        public WizardPage
        next() {
                InstrLocationMethodWizardPage p1 = instrLocationMethodWizardPage;
                WizardPage p2 = manualSelectWizardPage;
                
                if(getCurrentPage() == p1 && p1.isOrchestraMethodSelected()) {
                        super.next();
                } else if(getCurrentPage() == manualSelectWizardPage) {
                        super.next();
                }
                
                return super.next();
        }
        
        /**
         * Moves to the previous page in the wizard.
         * @return The previous page in the wizard.
         * @see #hasPrevious
         */
        public WizardPage
        previous() {
                InstrLocationMethodWizardPage p1 = instrLocationMethodWizardPage;
                WizardPage p2 = instrumentMappingWizardPage;
                
                if(getCurrentPage() == orchestraSelectWizardPage) {
                        super.previous();
                } else if(getCurrentPage() == p2 && !p1.isOrchestraMethodSelected()) {
                        super.previous();
                }
                
                return super.previous();
        }
        
        public void
        mapInstrument() {
                MidiInstrumentInfo instr = new MidiInstrumentInfo();
                if(instrLocationMethodWizardPage.isOrchestraMethodSelected()) {
                        Instrument i = orchestraSelectWizardPage.getInstrument();
                        instr.setFileName(i.getPath());
                        instr.setInstrumentIndex(i.getInstrumentIndex());
                        instr.setEngine(i.getEngine());
                        instr.setLoadMode(orchestraSelectWizardPage.getLoadMode());
                } else {
                        instr.setFileName(manualSelectWizardPage.getSelectedFile());
                        instr.setInstrumentIndex(manualSelectWizardPage.getInstrumentIndex());
                        instr.setEngine(manualSelectWizardPage.getEngine());
                        instr.setLoadMode(manualSelectWizardPage.getLoadMode());
                }
                
                int map = instrumentMappingWizardPage.getMapId();
                int bank = instrumentMappingWizardPage.getMidiBank();
                int prog = instrumentMappingWizardPage.getMidiProgram();
                
                instr.setName(instrumentMappingWizardPage.getInstrumentName());
                instr.setVolume(instrumentMappingWizardPage.getVolume());
                
                CC.getSamplerModel().mapBackendMidiInstrument(map, bank, prog, instr);
        }
}

class InstrLocationMethodWizardPage extends UserInputPage {
        private final JRadioButton rbManual =
                new JRadioButton(i18n.getLabel("InstrLocationMethodWizardPage.rbManual"));
        
        private final JRadioButton rbOrchestra =
                new JRadioButton(i18n.getLabel("InstrLocationMethodWizardPage.rbOrchestra"));
        
        private final JCheckBox checkSkip =
                new JCheckBox(i18n.getLabel("InstrLocationMethodWizardPage.checkSkip"));
        
        InstrLocationMethodWizardPage() {
                super(i18n.getLabel("InstrLocationMethodWizardPage.subtitle"));
                
                String s = i18n.getLabel("InstrLocationMethodWizardPage.mainInstructions");
                setMainInstructions(s);
                
                JPanel p = new JPanel();
                p.setLayout(new BoxLayout(p, BoxLayout.Y_AXIS));
                
                ButtonGroup group = new ButtonGroup();
                group.add(rbManual);
                group.add(rbOrchestra);
                rbManual.setSelected(true);
                
                p.add(rbManual);
                p.add(rbOrchestra);
                
                JPanel p2 = new JPanel();
                p2.setLayout(new BorderLayout());
                p2.add(p, BorderLayout.NORTH);
                p2.add(checkSkip, BorderLayout.SOUTH);
                setMainPane(p2);
                
                switch(ClassicPrefs.getInstrLocationMethod()) {
                case 0:
                        rbManual.setSelected(true);
                        break;
                case 1:
                        rbOrchestra.setSelected(true);
                }
                
                checkSkip.setSelected(ClassicPrefs.getNewMidiInstrWizardSkip1());
                
                rbManual.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) {
                                if(rbManual.isSelected()) ClassicPrefs.setInstrLocationMethod(0);
                        }
                });
                
                rbOrchestra.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) {
                                if(rbOrchestra.isSelected()) ClassicPrefs.setInstrLocationMethod(1);
                        }
                });
                
                checkSkip.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) {
                                ClassicPrefs.setNewMidiInstrWizardSkip1(checkSkip.isSelected());
                        }
                });
        }
        
        /**
         * Determines whether the user selected an orchestra location method.
         */
        public boolean
        isOrchestraMethodSelected() { return rbOrchestra.isSelected(); }
}

class OrchestraSelectWizardPage extends UserInputPage {
        private final JLabel lOrchestras =
                new JLabel(i18n.getLabel("OrchestraSelectWizardPage.lOrchestras"));
        
        private final JLabel lInstruments =
                new JLabel(i18n.getLabel("OrchestraSelectWizardPage.lInstruments"));
        
        private final JLabel lLoadMode =
                new JLabel(i18n.getLabel("OrchestraSelectWizardPage.lLoadMode"));
        
        private final JComboBox cbOrchestras = new JComboBox();
        private final JComboBox cbInstruments = new JComboBox();
        private final JComboBox cbLoadMode = new JComboBox();
        
        OrchestraSelectWizardPage() {
                super(i18n.getLabel("OrchestraSelectWizardPage.subtitle"));
                setMainInstructions(i18n.getLabel("OrchestraSelectWizardPage.mainInstructions"));
                
                GridBagLayout gridbag = new GridBagLayout();
                GridBagConstraints c = new GridBagConstraints();
                
                JPanel p = new JPanel();
                
                p.setLayout(gridbag);
                
                c.fill = GridBagConstraints.NONE;
                
                c.gridx = 0;
                c.gridy = 0;
                c.anchor = GridBagConstraints.EAST;
                c.insets = new Insets(0, 0, 6, 16);
                gridbag.setConstraints(lOrchestras, c);
                p.add(lOrchestras); 
                
                c.gridx = 0;
                c.gridy = 1;
                gridbag.setConstraints(lInstruments, c);
                p.add(lInstruments);
                
                c.gridx = 0;
                c.gridy = 2;
                c.insets = new Insets(12, 0, 6, 16);
                gridbag.setConstraints(lLoadMode, c);
                p.add(lLoadMode);
                
                c.gridx = 1;
                c.gridy = 0;
                c.weightx = 1.0;
                c.insets = new Insets(0, 0, 6, 48);
                c.fill = GridBagConstraints.HORIZONTAL;
                c.anchor = GridBagConstraints.NORTH;
                gridbag.setConstraints(cbOrchestras, c);
                p.add(cbOrchestras); 
                
                c.gridx = 1;
                c.gridy = 1;
                gridbag.setConstraints(cbInstruments, c);
                p.add(cbInstruments);
                
                c.gridx = 1;
                c.gridy = 2;
                c.insets = new Insets(12, 0, 6, 48);
                gridbag.setConstraints(cbLoadMode, c);
                p.add(cbLoadMode);
                
                JPanel p2 = new JPanel();
                p2.setOpaque(false);
                c.gridx = 0;
                c.gridy = 3;
                c.fill = GridBagConstraints.VERTICAL;
                c.weightx = 0.0;
                c.weighty = 1.0;
                gridbag.setConstraints(p2, c);
                p.add(p2);
                
                setMainPane(p);
                
                cbOrchestras.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) { orchestraChanged(); }
                });
                
                for(int i = 0; i < CC.getOrchestras().getOrchestraCount(); i++) {
                        cbOrchestras.addItem(CC.getOrchestras().getOrchestra(i));
                }
                
                cbInstruments.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) { instrumentChanged(); }
                });
                
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.DEFAULT);
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.ON_DEMAND);
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.ON_DEMAND_HOLD);
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.PERSISTENT);
        }
        
        private void
        orchestraChanged() {
                OrchestraModel om = (OrchestraModel)cbOrchestras.getSelectedItem();
                String s = om == null ? null : om.getDescription();
                if(s != null && s.length() == 0) s = null;
                cbOrchestras.setToolTipText(s);
                
                cbInstruments.removeAllItems();
                if(om == null || om.getInstrumentCount() == 0) {
                        cbInstruments.setEnabled(false);
                        return;
                }
                
                cbInstruments.setEnabled(true);
                
                for(int i = 0; i < om.getInstrumentCount(); i++) {
                        cbInstruments.addItem(om.getInstrument(i));
                }
        }
        
        private void
        instrumentChanged() {
                Instrument instr = (Instrument)cbInstruments.getSelectedItem();
                String s = instr == null ? null : instr.getDescription();
                if(s != null && s.length() == 0) s = null;
                cbInstruments.setToolTipText(s);
                
                getWizard().enableNextButton(instr != null);
        }
        
        public void
        postinitPage() {
                getWizard().enableNextButton(cbInstruments.getSelectedItem() != null);
        }
        
        /**
         * Gets the selected instrument.
         */
        public Instrument
        getInstrument() { return (Instrument)cbInstruments.getSelectedItem(); }
        
        /**
         * Gets the selected load mode.
         */
        public MidiInstrumentInfo.LoadMode
        getLoadMode() { return (MidiInstrumentInfo.LoadMode) cbLoadMode.getSelectedItem(); }
}

class ManualSelectWizardPage extends UserInputPage {
        private final JLabel lFilename =
                new JLabel(i18n.getLabel("ManualSelectWizardPage.lFilename"));
        
        private final JLabel lIndex = new JLabel(i18n.getLabel("ManualSelectWizardPage.lIndex"));
        
        private final JLabel lEngine = new JLabel(i18n.getLabel("ManualSelectWizardPage.lEngine"));
        
        private final JLabel lLoadMode =
                new JLabel(i18n.getLabel("ManualSelectWizardPage.lLoadMode"));
        
        private final JTextField tfFilename = new JTextField();
        private final JSpinner spinnerIndex = new JSpinner(new SpinnerNumberModel(0, 0, 500, 1));
        
        private final JButton btnBrowse =
                new JButton(Res.iconFolderOpen16);
        
        private final JComboBox cbEngine = new JComboBox();
        private final JComboBox cbLoadMode = new JComboBox();
        
        ManualSelectWizardPage() {
                super(i18n.getLabel("ManualSelectWizardPage.subtitle"));
                setMainInstructions(i18n.getLabel("ManualSelectWizardPage.mainInstructions"));
                
                GridBagLayout gridbag = new GridBagLayout();
                GridBagConstraints c = new GridBagConstraints();
                
                JPanel mainPane = new JPanel();
                
                mainPane.setLayout(gridbag);
                
                c.fill = GridBagConstraints.NONE;
                
                c.gridx = 0;
                c.gridy = 0;
                c.anchor = GridBagConstraints.EAST;
                c.insets = new Insets(3, 3, 3, 3);
                gridbag.setConstraints(lFilename, c);
                mainPane.add(lFilename); 
                
                c.gridx = 0;
                c.gridy = 1;
                gridbag.setConstraints(lIndex, c);
                mainPane.add(lIndex);
                
                c.gridx = 0;
                c.gridy = 2;
                c.insets = new Insets(12, 3, 3, 3);
                gridbag.setConstraints(lEngine, c);
                mainPane.add(lEngine);
                
                c.gridx = 0;
                c.gridy = 3;
                c.insets = new Insets(3, 3, 3, 3);
                gridbag.setConstraints(lLoadMode, c);
                mainPane.add(lLoadMode);
                
                btnBrowse.setMargin(new Insets(0, 0, 0, 0));
                btnBrowse.setToolTipText(i18n.getLabel("ManualSelectWizardPage.btnBrowse"));
                c.gridx = 2;
                c.gridy = 0;
                gridbag.setConstraints(btnBrowse, c);
                mainPane.add(btnBrowse);
                
                c.fill = GridBagConstraints.HORIZONTAL;
                c.gridx = 1;
                c.gridy = 0;
                c.weightx = 1.0;
                c.anchor = GridBagConstraints.WEST;
                gridbag.setConstraints(tfFilename, c);
                mainPane.add(tfFilename);
                        
                c.gridx = 1;
                c.gridy = 1;
                gridbag.setConstraints(spinnerIndex, c);
                mainPane.add(spinnerIndex);
                
                c.gridx = 1;
                c.gridy = 2;
                c.insets = new Insets(12, 3, 3, 64);
                gridbag.setConstraints(cbEngine, c);
                mainPane.add(cbEngine);
                
                c.gridx = 1;
                c.gridy = 3;
                c.insets = new Insets(3, 3, 3, 64);
                gridbag.setConstraints(cbLoadMode, c);
                mainPane.add(cbLoadMode);
                
                JPanel p2 = new JPanel();
                p2.setOpaque(false);
                c.gridx = 0;
                c.gridy = 4;
                c.fill = GridBagConstraints.VERTICAL;
                c.weightx = 0.0;
                c.weighty = 1.0;
                gridbag.setConstraints(p2, c);
                mainPane.add(p2);
                
                setMainPane(mainPane);
                
                tfFilename.getDocument().addDocumentListener(getHandler());
                
                btnBrowse.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) { onBrowse(); }
                });
                
                for(SamplerEngine e : CC.getSamplerModel().getEngines()) cbEngine.addItem(e);
                
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.DEFAULT);
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.ON_DEMAND);
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.ON_DEMAND_HOLD);
                cbLoadMode.addItem(MidiInstrumentInfo.LoadMode.PERSISTENT);
        }
        
        private void
        onBrowse() {
                JFileChooser fc = new JFileChooser();
                int result = fc.showOpenDialog(this);
                if(result == JFileChooser.APPROVE_OPTION) {
                        tfFilename.setText(fc.getSelectedFile().getPath());
                }
        }
        
        private void
        updateState() { getWizard().enableNextButton(tfFilename.getText().length() != 0); }
        
        public void
        postinitPage() {
                updateState();
        }
        
        /**
         * Gets the name of the instrument file.
         * @return The name of the instrument file.
         */
        public String
        getSelectedFile() { return tfFilename.getText(); }
        
        /**
         * Gets the index of the instrument in the instrument file.
         * @return The index of the instrument in the instrument file.
         */
        public int
        getInstrumentIndex() { return Integer.parseInt(spinnerIndex.getValue().toString()); }
        
        /**
         * Gets the selected engine.
         */
        public String
        getEngine() { return ((SamplerEngine)cbEngine.getSelectedItem()).getName(); }
        
        /**
         * Gets the selected load mode.
         */
        public MidiInstrumentInfo.LoadMode
        getLoadMode() { return (MidiInstrumentInfo.LoadMode)cbLoadMode.getSelectedItem(); }
        
        private final Handler eventHandler = new Handler();
        
        private Handler
        getHandler() { return eventHandler; }
        
        private class Handler implements DocumentListener {
                // DocumentListener
                public void
                insertUpdate(DocumentEvent e) { updateState(); }
                
                public void
                removeUpdate(DocumentEvent e) { updateState(); }
                
                public void
                changedUpdate(DocumentEvent e) { updateState(); }
        }
}

class InstrumentMappingWizardPage extends WizardPage  {
        private final JLabel lName = new JLabel(i18n.getLabel("InstrumentMappingWizardPage.lName"));
        private final JLabel lMap = new JLabel(i18n.getLabel("InstrumentMappingWizardPage.lMap"));
        private final JLabel lBank = new JLabel(i18n.getLabel("InstrumentMappingWizardPage.lBank"));
        private final JLabel lProgram =
                new JLabel(i18n.getLabel("InstrumentMappingWizardPage.lProgram"));
        
        private final JLabel lVolume =
                new JLabel(i18n.getLabel("InstrumentMappingWizardPage.lVolume"));
        
        private final JTextField tfName = new JTextField();
        private final JComboBox cbMap = new JComboBox();
        private final JSpinner spinnerBank = new JSpinner(new SpinnerNumberModel(0, 0, 16383, 1));
        private final JComboBox cbProgram = new JComboBox();
        private final JSlider slVolume = new JSlider(0, 100, 100);
        
        InstrumentMappingWizardPage() {
                super(i18n.getLabel("InstrumentMappingWizardPage.subtitle"));
                setPageType(Type.CONFIRMATION_PAGE);
                
                GridBagLayout gridbag = new GridBagLayout();
                GridBagConstraints c = new GridBagConstraints();
                
                setLayout(gridbag);
                
                c.fill = GridBagConstraints.NONE;
                
                c.gridx = 0;
                c.gridy = 0;
                c.anchor = GridBagConstraints.EAST;
                c.insets = new Insets(24, 3, 3, 0);
                gridbag.setConstraints(lName, c);
                add(lName); 
                
                c.gridx = 0;
                c.gridy = 2;
                c.insets = new Insets(3, 3, 3, 0);
                gridbag.setConstraints(lMap, c);
                add(lMap);
                
                c.gridx = 0;
                c.gridy = 3;
                gridbag.setConstraints(lBank, c);
                add(lBank);
                
                c.gridx = 0;
                c.gridy = 4;
                gridbag.setConstraints(lProgram, c);
                add(lProgram);
                
                c.gridx = 0;
                c.gridy = 1;
                c.insets = new Insets(3, 3, 24, 0);
                gridbag.setConstraints(lVolume, c);
                add(lVolume);
                
                c.fill = GridBagConstraints.HORIZONTAL;
                c.gridx = 1;
                c.gridy = 0;
                c.weightx = 1.0;
                c.insets = new Insets(24, 12, 3, 36);
                c.anchor = GridBagConstraints.WEST;
                gridbag.setConstraints(tfName, c);
                add(tfName);
                        
                c.gridx = 1;
                c.gridy = 2;
                c.insets = new Insets(3, 12, 3, 36);
                gridbag.setConstraints(cbMap, c);
                add(cbMap);
                
                c.gridx = 1;
                c.gridy = 3;
                gridbag.setConstraints(spinnerBank, c);
                add(spinnerBank);
                
                c.gridx = 1;
                c.gridy = 4;
                gridbag.setConstraints(cbProgram, c);
                add(cbProgram);
                
                c.gridx = 1;
                c.gridy = 1;
                c.insets = new Insets(3, 12, 24, 36);
                gridbag.setConstraints(slVolume, c);
                add(slVolume);
                
                JPanel p2 = new JPanel();
                p2.setOpaque(false);
                c.gridx = 0;
                c.gridy = 5;
                c.insets = new Insets(0, 0, 0, 0);
                c.fill = GridBagConstraints.VERTICAL;
                c.weightx = 0.0;
                c.weighty = 1.0;
                gridbag.setConstraints(p2, c);
                add(p2);
                
                cbMap.addActionListener(new ActionListener() {
                        public void
                        actionPerformed(ActionEvent e) { updateState(); }
                });
                
                for(MidiInstrumentMap m : CC.getSamplerModel().getMidiInstrumentMaps()) {
                        cbMap.addItem(m);
                }
                
                tfName.getDocument().addDocumentListener(getHandler());
                
                cbMap.setEnabled(cbMap.getItemCount() > 0);
                
                
                for(int i = 0; i < 128; i++) cbProgram.addItem(new Integer(i));
        }
        
        private void
        updateState() {
                cbMap.setEnabled(cbMap.getItemCount() > 0);
                boolean b = cbMap.getSelectedItem() != null;
                spinnerBank.setEnabled(b);
                cbProgram.setEnabled(b);
                
                b = tfName.getText().length() > 0 && cbMap.getSelectedItem() != null;
                b = b && cbProgram.getSelectedItem() != null;
                if(getWizard() != null) getWizard().enableFinishButton(b);
        }
        
        public void
        postinitPage() {
                updateState();
        }
        
        /**
         * Invoked when the user clicks the 'Finish' button
         * while this page is the current page of the wizard.
         * @return <code>true</code>
         */
        public boolean
        mayFinish() {
                ((NewMidiInstrumentWizardModel)getWizardModel()).mapInstrument();
                return true;
        }
        
        /**
         * Gets the ID of the selected MIDI instrument map.
         */
        public int
        getMapId() { return ((MidiInstrumentMap)cbMap.getSelectedItem()).getMapId(); }
        
        /**
         * Gets the selected MIDI bank.
         */
        public int
        getMidiBank() { return Integer.parseInt(spinnerBank.getValue().toString()); }
        
        /**
         * Gets the selected MIDI program.
         */
        public int
        getMidiProgram() { return cbProgram.getSelectedIndex(); }
        
        /**
         * Gets the chosen name for the new MIDI instrument.
         * @return The chosen name for the new MIDI instrument.
         */
        public String
        getInstrumentName() { return tfName.getText(); }
        
        /**
         * Returns the volume level of the new MIDI instrument.
         * @return The volume level of the new MIDI instrument.
         */
        public float
        getVolume() {
                float f = slVolume.getValue();
                f /= 100;
                return f;
        }
        
        private final Handler eventHandler = new Handler();
        
        private Handler
        getHandler() { return eventHandler; }
        
        private class Handler implements DocumentListener {
                // DocumentListener
                public void
                insertUpdate(DocumentEvent e) { updateState(); }
                
                public void
                removeUpdate(DocumentEvent e) { updateState(); }
                
                public void
                changedUpdate(DocumentEvent e) { updateState(); }
        }
}