sketchframe.java

一个利用java 实现的具有简单的画图功能的小程序

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

import java.awt.Color;
import java.awt.BorderLayout;

import java.io.File;

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

public class SketchFrame extends JFrame {
  // Constructor
  public SketchFrame(String title, Sketcher theApp) {
    setTitle(title);                             // Set the window title
    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
    fileMenu.setMnemonic('F');                   // Create shortcut
    elementMenu.setMnemonic('E');                // 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");
    closeAction = new FileAction("Close");
    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");

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

    // 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.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")));

    menuBar.add(fileMenu);                       // Add the file menu
    menuBar.add(elementMenu);                    // Add the element menu

    // Add file buttons
    toolBar.addSeparator();                      // Space at the start
    addToolBarButton(newAction);
    addToolBarButton(openAction);
    addToolBarButton(saveAction);
    addToolBarButton(printAction);
   
    // Add element type buttons
    toolBar.addSeparator();
    addToolBarButton(lineAction);
    addToolBarButton(rectangleAction);
    addToolBarButton(circleAction);
    addToolBarButton(curveAction);

    // 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);

    // Disable actions
    saveAction.setEnabled(false);
    closeAction.setEnabled(false);
    printAction.setEnabled(false);
  }

  // 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;
 }

  // Method making the current element color available
  public Color getElementColor() { 
    return elementColor; 
  }

  // Method making the current element type available
  public int getElementType() { 
    return elementType; 
  }

  // Inner class defining Action objects for File menu items
  class FileAction extends AbstractAction {    
    // Constructor to implement an accelerator and a tooltip
    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
      }
    }

    // Constructor to implement a tooltip
    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
      }
    }

    // Constructor
    FileAction(String name) {
      super(name);
      String iconFileName = "Images/" + name + ".gif";
      if(new File(iconFileName).exists()) {
        putValue(SMALL_ICON, new ImageIcon(iconFileName));
      }
    }

   // Constructor
    FileAction(String name, KeyStroke keystroke) {
      this(name);
      if(keystroke != null) {
        putValue(ACCELERATOR_KEY, keystroke);
      }
    }

    // Event handler
    public void actionPerformed(ActionEvent e) {
      // You will add action code here eventually...
    }
  }

  // Inner class defining Action objects for Element type menu items
  class TypeAction extends AbstractAction {    
    // Constructor to implement a tooltip
    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
      }
    }

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

    private int typeID;
  }

  // Handles color menu items
  class ColorAction  extends AbstractAction {
    // Constructor to implement a tooltip
    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 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 void actionPerformed(ActionEvent e) {
      elementColor = color;
    }

    private Color color;
  }

  // File actions
  private FileAction newAction, openAction, closeAction,
                     saveAction, saveAsAction, printAction;

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

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

  private JMenuBar menuBar = new JMenuBar();           // Window menu bar
  private JToolBar toolBar = new JToolBar();           // Window toolbar
  private Color elementColor = DEFAULT_ELEMENT_COLOR;  // Current element color
  private int elementType = DEFAULT_ELEMENT_TYPE;      // Current element type
  private Sketcher theApp;                             // The application object
}