source: josm/src/org/openstreetmap/josm/gui/Main.java@ 18

// Licence: GPL
package org.openstreetmap.josm.gui;

import java.awt.BorderLayout;
import java.awt.Container;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JToolBar;
import javax.swing.UIManager;

import org.openstreetmap.josm.actions.ExitAction;
import org.openstreetmap.josm.actions.OpenGpxAction;
import org.openstreetmap.josm.actions.OpenOsmServerAction;
import org.openstreetmap.josm.actions.PreferencesAction;
import org.openstreetmap.josm.actions.SaveGpxAction;
import org.openstreetmap.josm.data.Preferences;
import org.openstreetmap.josm.data.Preferences.PreferencesException;

/**
 * Main window class consisting of the mainframe MDI application.
 *  
 * @author imi
 */
public class Main extends JFrame {

        /**
         * Global application window. Use this as JOPtionPane-parent to center on application.
         */
        public static Main main;

        /**
         * Global application preferences
         */
        public final static Preferences pref = new Preferences();
        
        /**
         * The main panel.
         */
        private Container panel;
        /**
         * The name of the current loaded mapFrame
         */
        private String name;
        /**
         * The mapFrame currently loaded.
         */
        private MapFrame mapFrame;
        
        /**
         * Construct an main frame, ready sized and operating. Does not 
         * display the frame.
         */
        public Main() {
                super("Java Open Street Map - Editor");
                setLayout(new BorderLayout());
                panel = new JPanel(new BorderLayout());
                getContentPane().add(panel, BorderLayout.CENTER);
                setSize(1000,740); // some strange default size
                setExtendedState(MAXIMIZED_BOTH); // some platform are able to maximize
                
                // creating actions
                OpenOsmServerAction openServerAction = new OpenOsmServerAction();
                OpenGpxAction openGpxAction = new OpenGpxAction();
                SaveGpxAction saveGpxAction = new SaveGpxAction();
                ExitAction exitAction = new ExitAction();
                PreferencesAction preferencesAction = new PreferencesAction();

                // creating menu
                JMenuBar mainMenu = new JMenuBar();
                setJMenuBar(mainMenu);

                JMenu fileMenu = new JMenu("Files");
                fileMenu.setMnemonic('F');
                fileMenu.add(openGpxAction);
                fileMenu.add(saveGpxAction);
                fileMenu.addSeparator();
                fileMenu.add(exitAction);
                mainMenu.add(fileMenu);
                
                JMenu connectionMenu = new JMenu("Connection");
                connectionMenu.setMnemonic('C');
                connectionMenu.add(openServerAction);
                mainMenu.add(connectionMenu);
                
                JMenu editMenu = new JMenu("Edit");
                editMenu.setMnemonic('E');
                editMenu.add(preferencesAction);
                mainMenu.add(editMenu);

                // creating toolbar
                JToolBar toolBar = new JToolBar();
                toolBar.setFloatable(false);
                toolBar.add(openServerAction);
                toolBar.add(openGpxAction);
                toolBar.add(saveGpxAction);
                toolBar.addSeparator();
                toolBar.add(preferencesAction);
                
                getContentPane().add(toolBar, BorderLayout.NORTH);
        }

        /**
         * Main application Startup
         * @param args  No parameters accepted.
         */
        public static void main(String[] args) {
                setupUiDefaults();
                
                // load preferences
                String errMsg = null;
                try {
                        pref.load();
                } catch (PreferencesException e1) {
                        e1.printStackTrace();
                        errMsg = "Preferences could not be loaded. Write default preference file to '"+Preferences.getPreferencesFile()+"'.";
                        try {
                                pref.save();
                        } catch (PreferencesException e) {
                                e.printStackTrace();
                                errMsg = "Preferences could not be loaded. Reverting to default.";
                        }
                }
                if (errMsg != null)
                        JOptionPane.showMessageDialog(null, errMsg);
                
                try {
                        UIManager.setLookAndFeel(pref.laf.getClassName());
                } catch (Exception e) {
                        e.printStackTrace();
                }
                
                main = new Main();
                main.setDefaultCloseOperation(EXIT_ON_CLOSE);
                main.setVisible(true);
        }


        /**
         * Set the main's mapframe. If a changed old mapFrame is already set, 
         * ask the user whether he want to save, discard or abort. If the user
         * aborts, nothing happens. 
         */
        public void setMapFrame(String name, MapFrame mapFrame) {
                //TODO: Check for changes and ask user
                this.name = name;
                if (this.mapFrame != null)
                        this.mapFrame.setVisible(false);
                this.mapFrame = mapFrame;
                panel.setVisible(false);
                panel.removeAll();
                if (mapFrame != null) {
                        mapFrame.fillPanel(panel);
                        panel.setVisible(true);
                        mapFrame.setVisible(true);
                }
        }
        /**
         * @return Returns the name.
         */
        public String getNameOfLoadedMapFrame() {
                return name;
        }
        /**
         * @return Returns the mapFrame.
         */
        public MapFrame getMapFrame() {
                return mapFrame;
        }

        
        /**
         * Sets some icons to the ui.
         */
        private static void setupUiDefaults() {
                UIManager.put("OptionPane.okIcon", ImageProvider.get("ok"));
                UIManager.put("OptionPane.yesIcon", UIManager.get("OptionPane.okIcon"));
                UIManager.put("OptionPane.cancelIcon", ImageProvider.get("cancel"));
                UIManager.put("OptionPane.noIcon", UIManager.get("OptionPane.cancelIcon"));
        }
}