scribble.java

java 的164个例子的源代码,包括了 很多方面,供包括了19个方面的 源代码

/*
 * Copyright (c) 2000 David Flanagan.  All rights reserved.
 * This code is from the book Java Examples in a Nutshell, 2nd Edition.
 * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied.
 * You may study, use, and modify it for any non-commercial purpose.
 * You may distribute it non-commercially as long as you retain this notice.
 * For a commercial use license, or to purchase the book (recommended),
 * visit http://www.davidflanagan.com/javaexamples2.
 */
package com.davidflanagan.examples.gui;
import java.awt.*;          
import java.awt.event.*;    
import javax.swing.*;       
import javax.swing.border.*;

/**
 * This JFrame subclass is a simple "paint" application.
 **/
public class Scribble extends JFrame {
    /**
     * The main method instantiates an instance of the class, sets it size,
     * and makes it visible on the screen
     **/
    public static void main(String[] args) {
	Scribble scribble = new Scribble();
	scribble.setSize(500, 300);
	scribble.setVisible(true);
    }

    // The scribble application relies on the ScribblePane2 component developed
    // earlier.  This field holds the ScribblePane2 instance it uses.
    ScribblePane2 scribblePane;

    /**
     * This constructor creates the GUI for this application.
     **/
    public Scribble() {
	super("Scribble");  // Call superclass constructor and set window title

	// Handle window close requests
	this.addWindowListener(new WindowAdapter() {
		public void windowClosing(WindowEvent e) { System.exit(0); }
	    });

	// All content of a JFrame (except for the menubar) goes in the
	// Frame's internal "content pane", not in the frame itself.
	// The same is true for JDialog and similar top-level containers.
	Container contentPane = this.getContentPane();

	// Specify a layout manager for the content pane
	contentPane.setLayout(new BorderLayout());

	// Create the main scribble pane component, give it a border, and
	// a background color, and add it to the content pane
	scribblePane = new ScribblePane2();
	scribblePane.setBorder(new BevelBorder(BevelBorder.LOWERED));
	scribblePane.setBackground(Color.white);
	contentPane.add(scribblePane, BorderLayout.CENTER);

	// Create a menubar and add it to this window.  Note that JFrame
	// handles menus specially and has a special method for adding them
	// outside of the content pane.
	JMenuBar menubar = new JMenuBar();  // Create a menubar
	this.setJMenuBar(menubar);          // Display it in the JFrame

	// Create menus and add to the menubar
	JMenu filemenu = new JMenu("File");
	JMenu colormenu = new JMenu("Color");
	menubar.add(filemenu);
	menubar.add(colormenu);
	
	// Create some Action objects for use in the menus and toolbars.
	// An Action combines a menu title and/or icon with an ActionListener.
	// These Action classes are defined as inner classes below.
	Action clear = new ClearAction();
	Action quit = new QuitAction();
	Action black = new ColorAction(Color.black);
	Action red = new ColorAction(Color.red);
	Action blue = new ColorAction(Color.blue);
	Action select = new SelectColorAction();

	// Populate the menus using Action objects
	filemenu.add(clear);
	filemenu.add(quit);
	colormenu.add(black);
	colormenu.add(red);
	colormenu.add(blue);
	colormenu.add(select);

	// Now create a toolbar, add actions to it, and add it to the
	// top of the frame (where it appears underneath the menubar)
	JToolBar toolbar = new JToolBar();
	toolbar.add(clear);
	toolbar.add(select);
	toolbar.add(quit);
	contentPane.add(toolbar, BorderLayout.NORTH);

	// Create another toolbar for use as a color palette and add to 
	// the left side of the window.
	JToolBar palette = new JToolBar();
	palette.add(black);
	palette.add(red);
	palette.add(blue);
	palette.setOrientation(SwingConstants.VERTICAL);
	contentPane.add(palette, BorderLayout.WEST);
    }

    /** This inner class defines the "clear" action that clears the scribble */
    class ClearAction extends AbstractAction {
	public ClearAction() {
	    super("Clear");  // Specify the name of the action
	}
	public void actionPerformed(ActionEvent e) { scribblePane.clear(); }
    }

    /** This inner class defines the "quit" action to quit the program */
    class QuitAction extends AbstractAction {
	public QuitAction() { super("Quit"); }
	public void actionPerformed(ActionEvent e) { 
	    // Use JOptionPane to confirm that the user really wants to quit
	    int response =
		JOptionPane.showConfirmDialog(Scribble.this, "Really Quit?");
	    if (response == JOptionPane.YES_OPTION) System.exit(0);
	}
    }

    /**
     * This inner class defines an Action that sets the current drawing color
     * of the ScribblePane2 component.  Note that actions of this type have
     * icons rather than labels
     **/
    class ColorAction extends AbstractAction {
	Color color;
	public ColorAction(Color color) {
	    this.color = color;
	    putValue(Action.SMALL_ICON, new ColorIcon(color)); // specify icon
	}
	public void actionPerformed(ActionEvent e) {
	    scribblePane.setColor(color);  // Set current drawing color
	}
    }

    /**
     * This inner class implements Icon to draw a solid 16x16 block of the
     * specified color.  Most icons are instances of ImageIcon, but since
     * we're only using solid colors here, it is easier to implement this
     * custom Icon type
     **/
    static class ColorIcon implements Icon {
	Color color;
	public ColorIcon(Color color) { this.color = color; }
	// These two methods specify the size of the icon
	public int getIconHeight() { return 16; }
	public int getIconWidth() { return 16; }
	// This method draws the icon
	public void paintIcon(Component c, Graphics g, int x, int y) {
	    g.setColor(color);
	    g.fillRect(x, y, 16, 16);
	}
    }

    /**
     * This inner class defines an Action that uses JColorChooser to allow
     * the user to select a drawing color
     **/
    class SelectColorAction extends AbstractAction {
	public SelectColorAction() { super("Select Color..."); }
	public void actionPerformed(ActionEvent e) {
	    Color color = JColorChooser.showDialog(Scribble.this,
						   "Select Drawing Color",
						   scribblePane.getColor());
	    if (color != null) scribblePane.setColor(color);
	}
    }
}