rtextscrollpane.java~2~

具有不同语法高亮的编辑器实例

/*
 * 11/14/2003
 *
 * RTextScrollPane.java - A JScrollPane that will only accept RTextAreas
 *                        so that it can display line numbers.
 * Copyright (C) 2003 Robert Futrell
 * [e-mail]
 * www.website.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
package org.fife.ui.rtextarea;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

import org.fife.ui.RScrollPane;

/**
 * An extension of <code>org.fife.ui.RScrollPane</code> that will only take
 * <code>RTextArea</code>s for its view.  This class has the ability to show
 * line numbers for its text component view.<p>
 *
 * NOTE:  This class has two different implementations of line numbers,
 * <code>LineNumberList</code> and <code>LineNumberBorder</code>.
 * Currently, <code>LineNumberBorder</code> is used as it is much faster;
 * however, <code>LineNumberList</code> is more "object-oriented" and
 * would allow for more user-interaction with the line numbers...
 *
 * @author Robert Futrell
 * @version 0.5
 */
public class RTextScrollPane
    extends RScrollPane
    implements ActionListener {

  /**
   *
   */
  private static final long serialVersionUID = 8915747239613176913L;

  public RTextArea textArea;

  // NOTE:  Change which line numbering scheme you use by changing the
  // boolean below.
  private LineNumberList lineNumberList; // More OO-ish.
  private LineNumberBorder lineNumberBorder; // Faster.
  private static final boolean usingLineNumberList = false;

      /*****************************************************************************/

  /*
       * NOTE:  This was just a test to see if we could identify lines with brackets
   * in them, and should be removed.
   private class WorkerThread implements Runnable {
   private javax.swing.text.Segment s;
   public WorkerThread() {
    s = new javax.swing.text.Segment();
   }
   public void run() {
    while (true) {
     try {
      if (textArea!=null && lineNumberBorder!=null) {
       lineNumberBorder.clearHighlightedLines();
       for (int i=0; i<textArea.getLineCount(); i++) {
        int start = textArea.getLineStartOffset(i);
        int end = textArea.getLineEndOffset(i);
        javax.swing.text.Document doc = textArea.getDocument();
        doc.getText(start,end-start, s);
        boolean hasLeft = false;
        boolean hasRight = false;
        for (int j=s.offset; j<s.offset+s.count; j++) {
         switch (s.array[j]) {
          case '{':
           hasLeft = true;
           break;
          case '}':
           hasRight = true;
           break;
         }
        }
        if (hasLeft || hasRight)
         lineNumberBorder.addHighlightedLine(i);
       }
      }
     } catch (Exception e) {
      e.printStackTrace();
     }
     try {
      Thread.sleep(3000);
     } catch (InterruptedException ie) {}
    }
   }
   }
   */

  /**
   * Creates a scroll pane with preferred size (width, height).  A default
   * value will be used for line number color (gray), and the current
   * line's line number will be highlighted.
   *
   * @param width The preferred width of <code>area</code>.
   * @param height The preferred height of <code>area</code>.
   * @param area The text area this scroll pane will contain.
   * @param lineNumbersEnabled Whether line numbers are initially enabled.
   */
  public RTextScrollPane(int width, int height, RTextArea area,
                         boolean lineNumbersEnabled) {
    this(width, height, area, lineNumbersEnabled, new Color(128, 128, 128));
  }

      /*****************************************************************************/

  /**
   * Creates a scroll pane with preferred size (width, height).
   *
   * @param width The preferred width of <code>area</code>.
   * @param height The preferred height of <code>area</code>.
   * @param area The text area this scroll pane will contain.
   * @param lineNumbersEnabled Whether line numbers are initially enabled.
   * @param lineNumberColor The color to use for line numbers.
   */
  public RTextScrollPane(int width, int height, RTextArea area,
                         boolean lineNumbersEnabled, Color lineNumberColor) {

    // Call RScrollPane's constructor.
    super(width, height, area);

    /*
     Thread workerThread = new Thread(new WorkerThread());
     workerThread.start();
     */

    // Create the text area and set it inside this scrollbar area.
    textArea = area;

    // Create the line number list for this document.
    if (usingLineNumberList) {
      lineNumberList = new LineNumberList(textArea, lineNumberColor);
      lineNumberList.setFont(new Font("monospaced", Font.PLAIN, 12));
    }
    else {
      enableEvents(AWTEvent.MOUSE_EVENT_MASK);
      lineNumberBorder = new LineNumberBorder(this, textArea,
                                              lineNumberColor);
      lineNumberBorder.setFont(new Font("monospaced", Font.PLAIN, 12));
    }
    setLineNumbersEnabled(lineNumbersEnabled);

    // Set miscellaneous properties.
    setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
    setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);

  }

      /*****************************************************************************/

  /**
   * Returns <code>true</code> if the line numbers are enabled and visible.
   *
   * @return Whether or not line numbers are visible.
   */
  public boolean areLineNumbersEnabled() {
    if (usingLineNumberList) {
      return (getRowHeader() == null);
    }
    return lineNumberBorder != null;
  }

      /*****************************************************************************/

  /**
   * This method is overridden so that if the user clicks in the line
   * number border, the caret is moved.<p>
   *
   * This method will ONLY work if LineNumberBorder is used
   * (not LineNumberList).
   *
   * @param e The mouse event.
   */
  public void processMouseEvent(MouseEvent e) {
    if (e.getID() == MouseEvent.MOUSE_CLICKED) {
      int y = getViewport().getViewPosition().y + e.getY();
      int pos = textArea.viewToModel(new Point(0, y));
      textArea.setCaretPosition(pos);
    }
    super.processMouseEvent(e);
  }

      /*****************************************************************************/

  /**
   * Toggles whether or not line numbers are visible.
   *
   * @param enabled Whether or not line numbers should be visible.
   */
  public void setLineNumbersEnabled(boolean enabled) {
    if (usingLineNumberList) {
      if (enabled) {
        lineNumberList.updateCellWidths();
        JViewport viewport = new JViewport() {
          public void setViewPosition(java.awt.Point p) {
            Component c = getView();
            if (c != null) {
              c.repaint();
              //getView().setLocation(-p.x, -p.y);
              //fireStateChanged();
            }
          }
        };
        viewport.setView(lineNumberList);
        setRowHeader(viewport);
        //setRowHeaderView(lineNumberList);
      }
      else {
        setRowHeaderView(null);
      }
    }
    else { // lineNumberBorder
      setViewportBorder(enabled ? lineNumberBorder : null);
      revalidate();
    }
  }

      /*****************************************************************************/

}