How to use

repaint

method

in

org.fife.ui.rtextarea.Gutter

/**
 * Repaints the gutter in a text area's scroll pane, if necessary.
 *
 * @param textArea The text area.
 */
public static void possiblyRepaintGutter(RTextArea textArea) {
  Gutter gutter = RSyntaxUtilities.getGutter(textArea);
  if (gutter!=null) {
    gutter.repaint();
  }
}

/**
 * Sets the color for the "border" line.
 *
 * @param color The new color.
 * @see #getBorderColor()
 */
public void setBorderColor(Color color) {
  ((GutterBorder)getBorder()).setColor(color);
  repaint();
}

repaint();

@Override
public void mouseClicked(MouseEvent e) {
  Point p = e.getPoint();
  int line = rowAtPoint(p);
  RSyntaxTextArea rsta = (RSyntaxTextArea)textArea;
  FoldManager fm = rsta.getFoldManager();
  Fold fold = fm.getFoldForLine(line);
  if (fold!=null) {
    fold.toggleCollapsedState();
    getGutter().repaint();
    textArea.repaint();
  }
}

private void handleDocumentEvent(DocumentEvent e, Shape a,
                  ViewFactory f) {
  int n = calculateLineCount();
  if (this.nlines != n) {
    this.nlines = n;
    WrappedSyntaxView.this.preferenceChanged(this, false, true);
    // have to repaint any views after the receiver.
    RSyntaxTextArea textArea = (RSyntaxTextArea)getContainer();
    textArea.repaint();
    // Must also revalidate container so gutter components, such
    // as line numbers, get updated for this line's new height
    Gutter gutter = RSyntaxUtilities.getGutter(textArea);
    if (gutter!=null) {
      gutter.revalidate();
      gutter.repaint();
    }
  }
  else if (a != null) {
    Component c = getContainer();
    Rectangle alloc = (Rectangle) a;
    c.repaint(alloc.x, alloc.y, alloc.width, alloc.height);
  }
}

/**
 * Repaints the gutter in a text area's scroll pane, if necessary.
 *
 * @param textArea The text area.
 */
public static void possiblyRepaintGutter(RTextArea textArea) {
  Gutter gutter = RSyntaxUtilities.getGutter(textArea);
  if (gutter!=null) {
    gutter.repaint();
  }
}

/**
 * Sets the color for the "border" line.
 *
 * @param color The new color.
 * @see #getBorderColor()
 */
public void setBorderColor(Color color) {
  ((GutterBorder)getBorder()).setColor(color);
  repaint();
}

/**
 * Sets the color for the "border" line.
 *
 * @param color The new color.
 * @see #getBorderColor()
 */
public void setBorderColor(Color color) {
  ((GutterBorder)getBorder()).setColor(color);
  repaint();
}

/**
 * Sets the color for the "border" line.
 *
 * @param color The new color.
 * @see #getBorderColor()
 */
public void setBorderColor(Color color) {
  ((GutterBorder)getBorder()).setColor(color);
  repaint();
}

repaint();

@Override
public void mouseClicked(MouseEvent e) {
  Point p = e.getPoint();
  int line = rowAtPoint(p);
  RSyntaxTextArea rsta = (RSyntaxTextArea)textArea;
  FoldManager fm = rsta.getFoldManager();
  Fold fold = fm.getFoldForLine(line);
  if (fold!=null) {
    fold.toggleCollapsedState();
    getGutter().repaint();
    textArea.repaint();
  }
}

private void handleDocumentEvent(DocumentEvent e, Shape a,
                  ViewFactory f) {
  int n = calculateLineCount();
  if (this.nlines != n) {
    this.nlines = n;
    WrappedSyntaxView.this.preferenceChanged(this, false, true);
    // have to repaint any views after the receiver.
    RSyntaxTextArea textArea = (RSyntaxTextArea)getContainer();
    textArea.repaint();
    // Must also revalidate container so gutter components, such
    // as line numbers, get updated for this line's new height
    Gutter gutter = RSyntaxUtilities.getGutter(textArea);
    if (gutter!=null) {
      gutter.revalidate();
      gutter.repaint();
    }
  }
  else if (a != null) {
    Component c = getContainer();
    Rectangle alloc = (Rectangle) a;
    c.repaint(alloc.x, alloc.y, alloc.width, alloc.height);
  }
}