drawapplet.java

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/*
 * @(#)DrawApplet.java 5.2
 *
 */

package CH.ifa.draw.applet;

import javax.swing.*;
import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.io.*;
import java.net.*;
import CH.ifa.draw.framework.*;
import CH.ifa.draw.standard.*;
import CH.ifa.draw.figures.*;
import CH.ifa.draw.util.*;


/**
 * DrawApplication defines a standard presentation for
 * a drawing editor that is run as an applet. The presentation is
 * customized in subclasses.<p>
 * Supported applet parameters: <br>
 * <i>DRAWINGS</i>: a blank separated list of drawing names that is
 *           shown in the drawings choice.
 */

public class DrawApplet
        extends JApplet
	    implements DrawingEditor, PaletteListener {

    transient private Drawing         fDrawing;
    transient private Tool            fTool;

    transient private StandardDrawingView fView;
    transient private ToolButton      fDefaultToolButton;
    transient private ToolButton      fSelectedToolButton;

    transient private boolean         fSimpleUpdate;
    transient private JButton          fUpdateButton;

    transient private JComboBox          fFrameColor;
    transient private JComboBox          fFillColor;
    transient private JComboBox          fTextColor;
    transient private JComboBox          fArrowChoice;
    transient private JComboBox          fFontChoice;

    transient private Thread          fSleeper;
    private Iconkit                   fIconkit;

    static String                     fgUntitled = "untitled";

    private static final String       fgDrawPath = "/CH/ifa/draw/";
    public static final String        IMAGES = fgDrawPath+"images/";

    /**
     * Initializes the applet and creates its contents.
     */
    public void init() {
        fIconkit = new Iconkit(this);

		getContentPane().setLayout(new BorderLayout());

        fView = createDrawingView();
        
        JPanel attributes = createAttributesPanel();
        createAttributeChoices(attributes);
        getContentPane().add("North", attributes);

        JPanel toolPanel = createToolPalette();
        createTools(toolPanel);
        getContentPane().add("West", toolPanel);

        getContentPane().add("Center", fView);
        JPanel buttonPalette = createButtonPanel();
        createButtons(buttonPalette);
        getContentPane().add("South", buttonPalette);

        initDrawing();
        // JFC should have its own internal double buffering...
        //setBufferedDisplayUpdate();
        setupAttributes();
    }

    /*
     * Gets the iconkit to be used in the applet.
     */

     /**** not sure whether this will still be needed on 1.1 enabled browsers
     protected Iconkit iconkit() {
        if (fIconkit == null) {

            startSleeper();
            loadAllImages(this); // blocks until images loaded
            stopSleeper();
        }
        return fIconkit;
    } */

    /**
     * Creates the attributes panel.
     */
    protected JPanel createAttributesPanel() {
        JPanel panel = new JPanel();
        panel.setLayout(new PaletteLayout(2, new Point(2,2), false));
        return panel;
    }

    /**
     * Creates the attribute choices. Override to add additional
     * choices.
     */
    protected void createAttributeChoices(JPanel panel) {
        panel.add(new JLabel("Fill"));
        fFillColor = createColorChoice("FillColor");
        panel.add(fFillColor);

        panel.add(new JLabel("Text"));
        fTextColor = createColorChoice("TextColor");
        panel.add(fTextColor);

        panel.add(new JLabel("Pen"));
        fFrameColor = createColorChoice("FrameColor");
        panel.add(fFrameColor);

        panel.add(new JLabel("Arrow"));
        CommandChoice choice = new CommandChoice();
        fArrowChoice = choice;
        choice.addItem(new ChangeAttributeCommand("none",     "ArrowMode", new Integer(PolyLineFigure.ARROW_TIP_NONE),  fView));
        choice.addItem(new ChangeAttributeCommand("at Start", "ArrowMode", new Integer(PolyLineFigure.ARROW_TIP_START), fView));
        choice.addItem(new ChangeAttributeCommand("at End",   "ArrowMode", new Integer(PolyLineFigure.ARROW_TIP_END),   fView));
        choice.addItem(new ChangeAttributeCommand("at Both",  "ArrowMode", new Integer(PolyLineFigure.ARROW_TIP_BOTH),  fView));
        panel.add(fArrowChoice);

        panel.add(new JLabel("Font"));
        fFontChoice = createFontChoice();
        panel.add(fFontChoice);
    }

    /**
     * Creates the color choice for the given attribute.
     */
    protected JComboBox createColorChoice(String attribute) {
        CommandChoice choice = new CommandChoice();
        for (int i=0; i<ColorMap.size(); i++)
            choice.addItem(
                new ChangeAttributeCommand(
                    ColorMap.name(i),
                    attribute,
                    ColorMap.color(i),
                    fView
                )
            );
        return choice;
    }

    /**
     * Creates the font choice. The choice is filled with
     * all the fonts supported by the toolkit.
     */
    protected JComboBox createFontChoice() {
        CommandChoice choice = new CommandChoice();
        String fonts[] = Toolkit.getDefaultToolkit().getFontList();
        for (int i = 0; i < fonts.length; i++)
            choice.addItem(new ChangeAttributeCommand(fonts[i], "FontName", fonts[i],  fView));
        return choice;
    }

    /**
     * Creates the buttons panel.
     */
    protected JPanel createButtonPanel() {
        JPanel panel = new JPanel();
        panel.setLayout(new PaletteLayout(2, new Point(2,2), false));
        return panel;
    }

    /**
     * Creates the buttons shown in the buttons panel. Override to
     * add additional buttons.
     * @param panel the buttons panel.
     */
    protected void createButtons(JPanel panel) {
        panel.add(new Filler(24,20));

        JComboBox drawingChoice = new JComboBox();
        drawingChoice.addItem(fgUntitled);

	    String param = getParameter("DRAWINGS");
	    if (param == null)
	        param = "";
       	StringTokenizer st = new StringTokenizer(param);
        while (st.hasMoreTokens())
            drawingChoice.addItem(st.nextToken());
        // offer choice only if more than one
        if (drawingChoice.getItemCount() > 1)
            panel.add(drawingChoice);
        else
            panel.add(new JLabel(fgUntitled));

		drawingChoice.addItemListener(
		    new ItemListener() {
		        public void itemStateChanged(ItemEvent e) {
		            if (e.getStateChange() == ItemEvent.SELECTED) {
		                loadDrawing((String)e.getItem());
		            }
		        }
		    }
		);

        panel.add(new Filler(6,20));

        JButton button;
        button = new CommandButton(new DeleteCommand("Delete", fView));
        panel.add(button);

        button = new CommandButton(new DuplicateCommand("Duplicate", fView));
        panel.add(button);

        button = new CommandButton(new GroupCommand("Group", fView));
        panel.add(button);

        button = new CommandButton(new UngroupCommand("Ungroup", fView));
        panel.add(button);

        button = new JButton("Help");
		button.addActionListener(
		    new ActionListener() {
		        public void actionPerformed(ActionEvent event) {
		            showHelp();
		        }
		    }
		);
        panel.add(button);

        fUpdateButton = new JButton("Simple Update");
		fUpdateButton.addActionListener(
		    new ActionListener() {
		        public void actionPerformed(ActionEvent event) {
                    if (fSimpleUpdate)
                        setBufferedDisplayUpdate();
                    else
                        setSimpleDisplayUpdate();
		        }
		    }
		);

        // panel.add(fUpdateButton); // not shown currently
    }

    /**
     * Creates the tools palette.
     */
    protected JPanel createToolPalette() {
        JPanel palette = new JPanel();
        palette.setLayout(new PaletteLayout(2,new Point(2,2)));
        return palette;
    }

    /**
     * Creates the tools. By default only the selection tool is added.
     * Override this method to add additional tools.
     * Call the inherited method to include the selection tool.
     * @param palette the palette where the tools are added.
     */
    protected void createTools(JPanel palette) {
        Tool tool = createSelectionTool();

        fDefaultToolButton = createToolButton(IMAGES+"SEL", "Selection Tool", tool);
        palette.add(fDefaultToolButton);
    }

    /**