sketchframe.java

JAVA 2入门经典 练习答案

      if(keystroke != null)
        putValue(ACCELERATOR_KEY, keystroke);
    }

    FileAction(String name, String tooltip) {
      this(name);                                // Call the other constructor
      if(tooltip != null)                        // If there is tooltip text
        putValue(SHORT_DESCRIPTION, tooltip);    // ...squirrel it away
    }

    FileAction(String name, KeyStroke keystroke, String tooltip) {
      this(name, keystroke);                         // Call the other constructor
      if(tooltip != null)                             // If there is tooltip text
        putValue(SHORT_DESCRIPTION, tooltip);         // ...squirrel it away
    }
    
    // Event handler
    public void actionPerformed(ActionEvent e) {
      String name = (String)getValue(NAME);
      if(name.equals(saveAction.getValue(NAME))) {
        saveOperation();
      } else if(name.equals(saveAsAction.getValue(NAME))) {
       File file = showDialog("Save Sketch As",
                              "Save",
                              "Save the sketch",
                              's',
                              modelFile == null ? new File(
                                                files.getCurrentDirectory(),
                                                filename):modelFile);
       if(file != null) {
          if(file.exists() && !file.equals(modelFile))
           if(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 file selected
          saveSketch(file);
        }
        return;
      } else if(name.equals(openAction.getValue(NAME))) {
        checkForSave();

        // Now open a sketch file
        File file = showDialog(
                           "Open Sketch File",        // Dialog window title
                           "Open",                    // button lable
                           "Read a sketch from file", // Button tooltip text
                           'o',                       // Shortcut character
                           null);                     // No file selected
        if(file != null)                           // If a file was selected
          openSketch(file);                        // then read it
      } else if(name.equals(newAction.getValue(NAME))) {
        checkForSave();
        theApp.insertModel(new SketchModel());    // Insert new empty sketch
        modelFile = null;                         // No file for it
        filename = DEFAULT_FILENAME;              // Default name
        setTitle(frameTitle + files.getCurrentDirectory() + 
                 "\\" + filename);
        sketchChanged = false;                    // Not changed yet
      } else if(name.equals(closeAction.getValue(NAME))) {
        checkForSave();
        System.exit(0);
      } if(name.equals(printAction.getValue(NAME))) {
        // Get a printing object
        PrinterJob printJob = PrinterJob.getPrinterJob(); 

        PrintService printer = printJob.getPrintService();
        if(printer == null) {
          JOptionPane.showMessageDialog(SketchFrame.this,
                                        "No default printer available.",
                                        "Printer Error",
                                        JOptionPane.ERROR_MESSAGE);
          return;
        }
        // The view is the page source
        printJob.setPageable(theApp.getView());   // The view is the page source
        
        if(printJob.printDialog()) {     // Display print dialog
                                                  // If true is returned...
          try {
            printJob.print();                            // then print
          } catch(PrinterException pe) {
            System.out.println(pe);
            JOptionPane.showMessageDialog(SketchFrame.this,
                                          "Error printing a sketch.",
                                          "Printer Error",
                                          JOptionPane.ERROR_MESSAGE);
          }
        }
      }
    }
  }

  class TypeAction extends AbstractAction {    
    TypeAction(String name, int typeID) {
      super(name);
      this.typeID = typeID;
      String iconFileName = "Images/" + name + ".gif";
      if(new File(iconFileName).exists())
        putValue(SMALL_ICON, new ImageIcon(iconFileName));
    }
    
    TypeAction(String name, int typeID, String tooltip) {
      this(name, typeID);
      if(tooltip != null)                               // If there is a tooltip
        putValue(SHORT_DESCRIPTION, tooltip);           // ...squirrel it away
    }

    public void actionPerformed(ActionEvent e) {
      elementType = typeID;  
      statusBar.setTypePane(typeID);
    }

    private int typeID;
  }

  // Handles color menu items
  class ColorAction  extends AbstractAction {
    public ColorAction(String name, Color color) {
      super(name);
      this.color = color;
      String iconFileName = "Images/" + name + ".gif";
      if(new File(iconFileName).exists())
        putValue(SMALL_ICON, new ImageIcon(iconFileName));
    }
    
    public ColorAction(String name, Color color, String tooltip) {
      this(name, color);
       if(tooltip != null)                               // If there is a tooltip
         putValue(SHORT_DESCRIPTION, tooltip);           // ...squirrel it away
    }
    
    public void actionPerformed(ActionEvent e) {
      elementColor = color;
      statusBar.setColorPane(color);
    }

    private Color color;
  }

  private JMenuItem addMenuItem(JMenu menu, Action action) {
    JMenuItem item = menu.add(action);                  // Add the menu item

    KeyStroke keystroke = (KeyStroke)action.getValue(action.ACCELERATOR_KEY);
    if(keystroke != null)
      item.setAccelerator(keystroke);
      
    // remove this comments to disable icons
    // item.setIcon(null);                                 // Remove the icon
    return item;                                        // Return the menu item
  }

    public Color getElementColor() { 
      return elementColor; 
    }

  public int getElementType() { 
    return elementType; 
  }

  // Handle About menu action events
  public void actionPerformed(ActionEvent e)  {
    if(e.getSource() == aboutItem) {
      // Create about dialog with the menu item as parent
      JOptionPane.showMessageDialog(this,                          // Parent
                            "Sketcher Copyright Ivor Horton 2001", // Message
                            "About Sketcher",                      // Title
                            JOptionPane.INFORMATION_MESSAGE);      // Message type

    } else if(e.getSource() == fontItem) {      // Set the dialog window position
      Rectangle bounds = getBounds();
      fontDlg.setLocation(bounds.x + bounds.width/3, bounds.y + bounds.height/3);
      fontDlg.setVisible(true);            // Show the dialog

    } else if(e.getSource() == customColorItem) {
      Color color = JColorChooser.showDialog(this, "Select Custom Color",
                                                           elementColor);
      if(color != null) {
        elementColor = color;
        statusBar.setColorPane(color);
      }
    }
  }

    // Class defining a general purpose message box
  class AboutDialog extends JDialog implements ActionListener   {
    public AboutDialog(Frame parent, String title, String message)  {
      super(parent, title, true);
      // If there was a parent, set dialog position inside
      if(parent != null) {
        Dimension parentSize = parent.getSize();     // Parent size
        Point p = parent.getLocation();              // Parent position
        setLocation(p.x+parentSize.width/4,p.y+parentSize.height/4); 
      }

      // Create the message pane
      JPanel messagePane = new JPanel();
      messagePane.add(new JLabel(message));        
      getContentPane().add(messagePane);

      // Create the button pane
      JPanel buttonPane = new JPanel();
      JButton button = new JButton("OK");        // Create OK button
      buttonPane.add(button);                    // add to content pane
      button.addActionListener(this);
      getContentPane().add(buttonPane, BorderLayout.SOUTH);
      setDefaultCloseOperation(DISPOSE_ON_CLOSE);
      pack();                                    // Size window for components
      setVisible(true);
    }

    // OK button action
    public void actionPerformed(ActionEvent e)  {
      setVisible(false);                         // Set dialog invisible
      dispose();                                 // Release the dialog resources
    }
  }

  public Font getCurrentFont() {  
    return font;  
  }

  public void setCurrentFont(Font font) {  
    this.font = font;  
  }

  public String getSketchName() {
    return filename;
  }

  private JPopupMenu popup = new JPopupMenu("General");       // Window pop-up

  // Element color actions
  private ColorAction redAction, yellowAction, greenAction, blueAction;

  // Element type actions
  private TypeAction lineAction, rectangleAction, circleAction, curveAction, textAction;

  // File actions
  private FileAction newAction, openAction, closeAction, saveAction, saveAsAction, printAction;
  private XMLExportAction exportAction;    // Stores action for XML export menu item
  private XMLImportAction importAction;    // Stores action for XML import menu item

  private JMenuBar menuBar = new JMenuBar();     // Window menu bar

  private Color elementColor = DEFAULT_ELEMENT_COLOR;   // Current element color
  private int elementType = DEFAULT_ELEMENT_TYPE;       // Current element type

  private JToolBar toolBar = new JToolBar();      // Window toolbar
  private Sketcher theApp;

  private StatusBar statusBar = new StatusBar();    // Window status bar

  // Sundry menu items
  private JMenuItem aboutItem, fontItem;
  private Font font = DEFAULT_FONT;                      // Current font

  private FontDialog fontDlg;                      // The font dialog
  private String frameTitle;                  // Frame title
  private String filename = DEFAULT_FILENAME; // Current model file name
  private File modelFile;                     // File for the current sketch
  private boolean sketchChanged = false;         // Model changed flag
  private JFileChooser files;                   // File chooser dialog

  private JMenuItem customColorItem;

  private HashPrintRequestAttributeSet requestAttr = new  HashPrintRequestAttributeSet();
}