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--- swing:jtree_demo_01 [2015/05/17 16:56]
gthanos
+++ swing:jtree_demo_01 [2016/02/26 11:15]
@@ Line 1: / Line 1: @@
-====== TreeDemo ======
-Για την ορθή εκτέλεση του παρακάτω παραδείγματος θα χρειαστείτε και αυτά τα αρχεία html {{:swing:html.zip|}}.
-<code java TreeDemo.java>
-package components;
-/**
- * This application that requires the following additional files:
- *   TreeDemoHelp.html
- *  arnold.html
- *  bloch.html
- *  chan.html
- *  jls.html
- *  swingtutorial.html
- *  tutorial.html
- *  tutorialcont.html
- *  vm.html
- */
-import javax.swing.JEditorPane;
-import javax.swing.JFrame;
-import javax.swing.JPanel;
-import javax.swing.JScrollPane;
-import javax.swing.JSplitPane;
-import javax.swing.UIManager;
-import javax.swing.JTree;
-import javax.swing.tree.DefaultMutableTreeNode;
-import javax.swing.tree.TreeSelectionModel;
-import javax.swing.event.TreeSelectionEvent;
-import javax.swing.event.TreeSelectionListener;
-import javax.swing.event.*;
-import java.net.URL;
-import java.io.IOException;
-import java.awt.Dimension;
-import java.awt.GridLayout;
-public class TreeDemo extends JPanel
-            implements TreeSelectionListener, TreeModelListener {
-  private JEditorPane htmlPane;
-  private JTree tree;
-  private URL helpURL;
-  private static boolean DEBUG = false;
-  //Optionally play with line styles.  Possible values are
-  //"Angled" (the default), "Horizontal", and "None".
-  private static boolean playWithLineStyle = false;
-  private static String lineStyle = "Horizontal";
-  //Optionally set the look and feel.
-  private static boolean useSystemLookAndFeel = false;
-  public TreeDemo() {
-    super(new GridLayout(1,0));
-    //Create the nodes.
-    DefaultMutableTreeNode top =
-      new DefaultMutableTreeNode("The Java Series");
-    createNodes(top);
-    //Create a tree that allows one selection at a time.
-    tree = new JTree(top);
-    tree.setEditable(true);
-    tree.getSelectionModel().setSelectionMode
-        (TreeSelectionModel.SINGLE_TREE_SELECTION);
-    //Listen for when the selection changes.
-    tree.addTreeSelectionListener(this);
-    if (playWithLineStyle) {
-      System.out.println("line style = " + lineStyle);
-      tree.putClientProperty("JTree.lineStyle", lineStyle);
-    }
-    //Create the scroll pane and add the tree to it.
-    JScrollPane treeView = new JScrollPane(tree);
-    //Create the HTML viewing pane.
-    htmlPane = new JEditorPane();
-    htmlPane.setEditable(false);
-    initHelp();
-    JScrollPane htmlView = new JScrollPane(htmlPane);
-    //Add the scroll panes to a split pane.
-    JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
-    splitPane.setTopComponent(treeView);
-    splitPane.setBottomComponent(htmlView);
-    Dimension minimumSize = new Dimension(100, 50);
-    htmlView.setMinimumSize(minimumSize);
-    treeView.setMinimumSize(minimumSize);
-    splitPane.setDividerLocation(100);
-    splitPane.setPreferredSize(new Dimension(500, 300));
-    //Add the split pane to this panel.
-    add(splitPane);
-  }
-  /** Required by TreeSelectionListener interface. */
-  public void valueChanged(TreeSelectionEvent e) {
-    DefaultMutableTreeNode node = (DefaultMutableTreeNode)
-               tree.getLastSelectedPathComponent();
-    if (node == null) return;
-    Object nodeInfo = node.getUserObject();
-    if (node.isLeaf()) {
-      BookInfo book = (BookInfo)nodeInfo;
-      displayURL(book.bookURL);
-      if (DEBUG) {
-        System.out.print(book.bookURL + ":  \n  ");
-      }
-    } else {
-      displayURL(helpURL);
-    }
-    if (DEBUG) {
-      System.out.println(nodeInfo.toString());
-    }
-  }
-  public void treeNodesChanged(TreeModelEvent e){
-    System.out.println("Node changed\n");
-  }
-  public void treeNodesInserted(TreeModelEvent e){
-    System.out.println("Node inserted\n");
-  }
-  public void treeNodesRemoved(TreeModelEvent e){
-    System.out.println("Node deleted\n");
-  }
-  public void treeStructureChanged(TreeModelEvent e){
-    System.out.println("Tree structure changed\n");
-  }
-  private class BookInfo {
-    public String bookName;
-    public URL bookURL;
-    public BookInfo(String book, String filename) {
-      bookName = book;
-      bookURL = getClass().getResource("html/"+filename);
-      if (bookURL == null) {
-        System.err.println("Couldn't find file: "
-                   + filename);
-      }
-    }
-    public String toString() {
-      return bookName;
-    }
-  }
-  private void initHelp() {
-    String s = "TreeDemoHelp.html";
-    helpURL = getClass().getResource(s);
-    if (helpURL == null) {
-      System.err.println("Couldn't open help file: " + s);
-    } else if (DEBUG) {
-      System.out.println("Help URL is " + helpURL);
-    }
-    displayURL(helpURL);
-  }
-  private void displayURL(URL url) {
-    try {
-      if (url != null) {
-        htmlPane.setPage(url);
-      } else { //null url
-		htmlPane.setText("File Not Found");
-        if (DEBUG) {
-          System.out.println("Attempted to display a null URL.");
-        }
-      }
-    } catch (IOException e) {
-      System.err.println("Attempted to read a bad URL: " + url);
-    }
-  }
-  private void createNodes(DefaultMutableTreeNode top) {
-    DefaultMutableTreeNode category = null;
-    DefaultMutableTreeNode book = null;
-    category = new DefaultMutableTreeNode("Books for Java Programmers");
-    top.add(category);
-    //original Tutorial
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The Java Tutorial: A Short Course on the Basics",
-      "tutorial.html"));
-    category.add(book);
-    //Tutorial Continued
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The Java Tutorial Continued: The Rest of the JDK",
-      "tutorialcont.html"));
-    category.add(book);
-    //JFC Swing Tutorial
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The JFC Swing Tutorial: A Guide to Constructing GUIs",
-      "swingtutorial.html"));
-    category.add(book);
-    //Bloch
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("Effective Java Programming Language Guide",
-	   "bloch.html"));
-    category.add(book);
-    //Arnold/Gosling
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The Java Programming Language", "arnold.html"));
-    category.add(book);
-    //Chan
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The Java Developers Almanac",
-       "chan.html"));
-    category.add(book);
-    category = new DefaultMutableTreeNode("Books for Java Implementers");
-    top.add(category);
-    //VM
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The Java Virtual Machine Specification",
-       "vm.html"));
-    category.add(book);
-    //Language Spec
-    book = new DefaultMutableTreeNode(new BookInfo
-      ("The Java Language Specification",
-       "jls.html"));
-    category.add(book);
-  }
-  /**
-   * Create the GUI and show it.  For thread safety,
-   * this method should be invoked from the
-   * event dispatch thread.
-   */
-  private static void createAndShowGUI() {
-    if (useSystemLookAndFeel) {
-      try {
-        UIManager.setLookAndFeel(
-          UIManager.getSystemLookAndFeelClassName());
-      } catch (Exception e) {
-        System.err.println("Couldn't use system look and feel.");
-      }
-    }
-    //Create and set up the window.
-    JFrame frame = new JFrame("TreeDemo");
-    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
-    //Add content to the window.
-    frame.add(new TreeDemo());
-    //Display the window.
-    frame.pack();
-    frame.setVisible(true);
-  }
-  public static void main(String[] args) {
-    //Schedule a job for the event dispatch thread:
-    //creating and showing this application's GUI.
-    javax.swing.SwingUtilities.invokeLater(new Runnable() {
-      public void run() {
-        createAndShowGUI();
-      }
-    });
-  }
-}
-</code>

Αντικειμενοστραφής Προγραμματισμός, Εφαρμογές με χρήση της γλώσσας προγραμματισμού JAVA

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