sketchframe.java

用JAVA开发的一个小型画图软件

// Frame for the Sketcher application
import javax.swing.JFrame;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JRadioButtonMenuItem;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.ButtonGroup;
import javax.swing.KeyStroke;
import javax.swing.Action;
import javax.swing.AbstractAction;
import javax.swing.JToolBar;
import javax.swing.JButton;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JDialog;
import javax.swing.JPanel;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPopupMenu;
import javax.swing.JColorChooser;
import javax.swing.JFileChooser;

import javax.print.PrintService;
import java.awt.print.Printable;
import java.awt.print.PrinterJob;
import java.awt.print.PrinterException;
import java.awt.print.PageFormat;
import javax.print.attribute.HashPrintRequestAttributeSet;

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

import java.awt.Color;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.Font;
import java.awt.Rectangle;
import java.awt.Graphics;
import java.awt.Graphics2D;

import java.io.File;
import java.io.ObjectOutputStream;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.IOException;

import static java.awt.event.InputEvent.*;
import static java.awt.AWTEvent.*;
import static java.awt.Color.*;
import static Constants.SketcherConstants.*;

import java.util.Observer;
import java.util.Observable;

public class SketchFrame extends    JFrame 
                         implements ActionListener, Observer, Printable {  // Constructor
  public SketchFrame(String title, Sketcher theApp) {
    frameTitle = title + ": ";
    setTitle(frameTitle + filename);

    if(!DEFAULT_DIRECTORY.exists()) {
      if(!DEFAULT_DIRECTORY.mkdirs()) {
        JOptionPane.showMessageDialog(this,
                                      "Error creating default directory",
                                      "Directory Creation Error",
                                      JOptionPane.ERROR_MESSAGE);
      }
    }
    files = new JFileChooser(DEFAULT_DIRECTORY);
    this.theApp = theApp;                        // Save application object reference
    setJMenuBar(menuBar);                        // Add the menu bar to the window
    setDefaultCloseOperation(EXIT_ON_CLOSE);     // Default is exit the application

    JMenu fileMenu = new JMenu("File");          // Create File menu
    JMenu elementMenu = new JMenu("Elements");   // Create Elements menu
    JMenu optionsMenu = new JMenu("Options");    // Create options menu
    JMenu helpMenu = new JMenu("Help");          // Create Help menu

    fileMenu.setMnemonic('F');                   // Create shortcut
    elementMenu.setMnemonic('E');                // Create shortcut
    optionsMenu.setMnemonic('O');                // Create shortcut
    helpMenu.setMnemonic('H');                   // Create shortcut 
    
    // Create the action items for the file menu
    newAction = new FileAction("New", KeyStroke.getKeyStroke('N', CTRL_DOWN_MASK),"Create new sketch");
    openAction = new FileAction("Open", KeyStroke.getKeyStroke('O', CTRL_DOWN_MASK),"Open existing sketch");
    saveAction = new FileAction("Save", KeyStroke.getKeyStroke('S', CTRL_DOWN_MASK), "Save sketch");
    saveAsAction = new FileAction("Save As...");
    printAction = new FileAction("Print", KeyStroke.getKeyStroke('P', CTRL_DOWN_MASK), "Print sketch");
    closeAction = new FileAction("Exit",KeyStroke.getKeyStroke('X', CTRL_DOWN_MASK ), "Exit Sketcher");

    printSetupItem = new JMenuItem("Print Setup...");
    printSetupItem.addActionListener(this);
    printWindowItem = new JMenuItem("Print Window");
    printWindowItem.addActionListener(this);

    // Construct the file drop-down menu
    fileMenu.add(new JMenuItem(newAction));
    fileMenu.add(new JMenuItem(openAction));
    fileMenu.addSeparator();                     // Add separator
    fileMenu.add(new JMenuItem(saveAction));
    fileMenu.add(new JMenuItem(saveAsAction));
    fileMenu.addSeparator();                     // Add separator
    fileMenu.add(new JMenuItem(printAction));
    fileMenu.add(printSetupItem);
    fileMenu.add(printWindowItem);
    fileMenu.addSeparator();                     // Add separator
    fileMenu.add(new JMenuItem(closeAction));

    // Construct the Element drop-down menu
    elementMenu.add(new JMenuItem(lineAction = new TypeAction("Line", LINE, "Draw lines")));
    elementMenu.add(new JMenuItem(rectangleAction = new TypeAction("Rectangle", RECTANGLE, "Draw rectangles")));
    elementMenu.add(new JMenuItem(circleAction = new TypeAction("Circle", CIRCLE, "Draw circles")));
    elementMenu.add(new JMenuItem(curveAction = new TypeAction("Curve", CURVE, "Draw curves")));  
    elementMenu.add(new JMenuItem(textAction = new TypeAction("Text", TEXT, "Draw text")));
    elementMenu.addSeparator();

    JMenu colorMenu = new JMenu("Color");        // Color sub-menu
    elementMenu.add(colorMenu);                  // Add the sub-menu

    colorMenu.add(new JMenuItem(redAction = new ColorAction("Red", RED, "Draw in red")));
    colorMenu.add(new JMenuItem(yellowAction = new ColorAction("Yellow", YELLOW, "Draw in yellow")));
    colorMenu.add(new JMenuItem(greenAction = new ColorAction("Green", GREEN, "Draw in green")));
    colorMenu.add(new JMenuItem(blueAction = new ColorAction("Blue", BLUE, "Draw in blue")));

   // Add the font choice item to the options menu
    fontItem = new JMenuItem("Choose font...");
    fontItem.addActionListener(this);
    optionsMenu.add(fontItem);
   
    menuBar.add(fileMenu);                       // Add the file menu
    menuBar.add(elementMenu);                    // Add the element menu
    menuBar.add(optionsMenu);                    // Add the options menu
    menuBar.add(helpMenu);                       // Add the Help menu

    // Create pop-up menu
    popup.add(new JMenuItem(lineAction));
    popup.add(new JMenuItem(rectangleAction));
    popup.add(new JMenuItem(circleAction));
    popup.add(new JMenuItem(curveAction));
    popup.add(new JMenuItem(textAction));
    popup.addSeparator();
    popup.add(new JMenuItem(redAction));
    popup.add(new JMenuItem(yellowAction));
    popup.add(new JMenuItem(greenAction));
    popup.add(new JMenuItem(blueAction));
    customColorItem = popup.add(new JMenuItem("Custom Color...")); // Add the item
    customColorItem.addActionListener(this);     // and add its listener
 
    // Add file buttons
    toolBar.addSeparator();                      // Space at the start
    addToolBarButton(newAction);
    addToolBarButton(openAction);
    addToolBarButton(saveAction);
    printButton = addToolBarButton(printAction);
   
    // Add element type buttons
    toolBar.addSeparator();
    addToolBarButton(lineAction);
    addToolBarButton(rectangleAction);
    addToolBarButton(circleAction);
    addToolBarButton(curveAction);
    addToolBarButton(textAction);
    
    // Add element color buttons
    toolBar.addSeparator();
    addToolBarButton(redAction);
    addToolBarButton(yellowAction);
    addToolBarButton(greenAction);
    addToolBarButton(blueAction);
    toolBar.addSeparator();                      // Space at the end

    toolBar.setFloatable(false);                 // Inhibit toolbar floating
    toolBar.putClientProperty("JToolBar.isRollover",Boolean.TRUE);
    toolBar.setBorder(BorderFactory.createEtchedBorder(WHITE, LIGHT_GRAY));
    getContentPane().add(toolBar, BorderLayout.NORTH);

    getContentPane().add(statusBar, BorderLayout.SOUTH);   // Add the statusbar

    // Add the About item to the Help menu
    aboutItem = new JMenuItem("About");          // Create the item
    aboutItem.addActionListener(this);           // Listener is the frame
    helpMenu.add(aboutItem);                     // Add item to menu

    fontDlg = new FontDialog(this);              // Create the font dialog

    // Set up the printer and page format objects
    printJob = PrinterJob.getPrinterJob(); // Get a printing object
    pageFormat = printJob.defaultPage();   // Get the page format
    printer = printJob.getPrintService();  // Get the default printer
  }

  // Method to add a button to the toolbar
  private JButton addToolBarButton(Action action) {
    JButton button = new JButton(action);
    button.setBorder(BorderFactory.createRaisedBevelBorder());// Add button border
    button.setText(null);
    toolBar.add(button);
    return button;
 }

  // Print the window
  public int print(Graphics g,
                   PageFormat pageFormat,
                   int pageIndex)
             throws PrinterException {
    if(pageIndex>0)   // Only one page page 0 to be printed
      return NO_SUCH_PAGE;

    // Scale the component to fit
    Graphics2D g2D = (Graphics2D) g;

    // Calculate the scale factor to fit the window to the page
    double scaleX = pageFormat.getImageableWidth()/getWidth();
    double scaleY = pageFormat.getImageableHeight()/getHeight();

    double scale = Math.min(scaleX,scaleY);  // Get minimum scale factor

    // Move paper origin to page printing area corner
    g2D.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
    g2D.scale(scale,scale);                  // Apply the scale factor

    printAll(g2D);                           // Draw the component
    return PAGE_EXISTS;
  }

  // Display a custom file save dialog
  private File showDialog(String dialogTitle,
                          String approveButtonText,
                          String approveButtonTooltip,
                          File file) {           // Current file - if any

    files.setDialogTitle(dialogTitle);
    files.setApproveButtonText(approveButtonText);
    files.setApproveButtonToolTipText(approveButtonTooltip);
    files.setFileSelectionMode(files.FILES_ONLY);
    ExtensionFilter sketchFilter = new ExtensionFilter(".ske",
                                              "Sketch files (*.ske)");
    files.addChoosableFileFilter(sketchFilter);            // Add the filter
    files.setFileFilter(sketchFilter);                     // and select it
    files.rescanCurrentDirectory();
    files.setSelectedFile(file);
    files.rescanCurrentDirectory();
    files.setSelectedFile(file);
    int result = files.showDialog(SketchFrame.this, null);  // Show the dialog
    return (result == files.APPROVE_OPTION) ? files.getSelectedFile() : null;
  }

  // Save the sketch if it is necessary
  private void saveOperation() {
    if(!sketchChanged) {
      return;
    }

    File file = modelFile;
    if(file == null) {
      file = showDialog("Save Sketch",
                        "Save",
                        "Save the sketch",
                        new File(files.getCurrentDirectory(), filename));
      if(file == null ||  (file.exists() &&    // Check for existence
         JOptionPane.NO_OPTION ==              // Overwrite warning
              JOptionPane.showConfirmDialog(SketchFrame.this,
                                      file.getName()+" exists. Overwrite?",
                                      "Confirm Save As",
                                      JOptionPane.YES_NO_OPTION,
                                      JOptionPane.WARNING_MESSAGE)))
            return;                            // No selected file
    }
    saveSketch(file);    
  }

  // Write a sketch to outFile
  private void saveSketch(File outFile) {
    try {
      ObjectOutputStream out =  new ObjectOutputStream(
                                new BufferedOutputStream(
                                new FileOutputStream(outFile)));
      out.writeObject(theApp.getModel());        // Write the sketch to the stream
      out.close();                               // Flush & close it
    } catch(IOException e) {
      System.err.println(e);
      JOptionPane.showMessageDialog(SketchFrame.this,
                                    "Error writing a sketch file.",
                                    "File Output Error",
                                    JOptionPane.ERROR_MESSAGE);
      return;                                    // Serious error - return
    }
    if(outFile != modelFile) {             // If we are saving to a new file
                                           // we must update the window
      modelFile = outFile;                       // Save file reference
      filename = modelFile.getName();            // Update the file name
      setTitle(frameTitle + modelFile.getPath());  // Change the window title
    }
    sketchChanged = false;                       // Set as unchanged
  }

    // Prompt for save operation when necessary
    public void checkForSave() {
      if(sketchChanged && JOptionPane.YES_OPTION ==
              JOptionPane.showConfirmDialog(SketchFrame.this,
                               "Current file has changed. Save current file?",
                               "Confirm Save Current File",
                               JOptionPane.YES_NO_OPTION,
                               JOptionPane.WARNING_MESSAGE)) {
        saveOperation();
      }
    }

  // Method for opening file