/**
* Called to draw the panel.
*
* @param g Graphics device to draw the panel to.
*/
public void paintComponent(Graphics g) {
final Point scrollPosition = getScrollPosition();
g.translate(-scrollPosition.x, -scrollPosition.y);
try {
super.paintComponent(g);
} finally {
g.translate(scrollPosition.x, scrollPosition.y);
}
}
/**
* Called to recursively paint the check box for the specified item.
*
* @param item row number
* @param g graphics object to paint.
* @param bookmark to check selected value.
* @return the next row number to paint.
*/
public int paintCheckbox(final int item, final Graphics g, final Bookmark bookmark) {
int nextItem = item + 1;
if (bookmark != null) {
final Rectangle checkboxBounds =
getCheckboxBounds(item, bookmark, getDepthMap().get(bookmark));
final int yCheckboxMidPoint = checkboxBounds.y + (checkboxBounds.height / 2);
final int xCheckboxMidPoint = checkboxBounds.x + (checkboxBounds.width / 2);
final Enumeration e = bookmark.elements();
if (e.hasMoreElements()) {
// clear any lines crossing through the checkbox.
g.clearRect(
checkboxBounds.x, checkboxBounds.y, checkboxBounds.width, checkboxBounds.height);
// draw box around checkbox
g.drawRect(checkboxBounds.x, checkboxBounds.y, checkboxBounds.width, checkboxBounds.height);
// draw dash inside checkbox
g.drawLine(
checkboxBounds.x + 2,
yCheckboxMidPoint,
(checkboxBounds.x + checkboxBounds.width) - 2,
yCheckboxMidPoint);
boolean drawPlus = true;
do {
final Bookmark child = (Bookmark) e.nextElement();
final Bookmark next = getBookmark(nextItem);
if (child != next) {
break;
}
drawPlus = false;
nextItem = paintCheckbox(nextItem, g, child);
} while (e.hasMoreElements());
if (drawPlus) {
g.drawLine(
xCheckboxMidPoint,
checkboxBounds.y + 2,
xCheckboxMidPoint,
(checkboxBounds.y + checkboxBounds.height) - 2);
}
}
}
return nextItem;
}
/**
* Called to recursively paint text and lines for the specified item.
*
* @param item row number
* @param g graphics object to paint.
* @param bookmark to check selected value.
* @return the next row number to paint.
*/
public int paintItem(final int item, final Graphics g, final Bookmark bookmark) {
int nextItem = item + 1;
if (bookmark != null) {
final Rectangle textBounds = getTextBounds(item, bookmark, getDepthMap().get(bookmark));
final int yTextMidPoint = textBounds.y + (textBounds.height / 2);
final Enumeration e = bookmark.elements();
final String displayName = bookmark.getDisplayName();
if (displayName != null) {
g.drawString(displayName, textBounds.x, textBounds.y + textBounds.height);
}
if (e.hasMoreElements()) {
// draw line from checkbox to text
g.drawLine(textBounds.x - getFontWidth(), yTextMidPoint, textBounds.x - 2, yTextMidPoint);
final int xLineToChildren = textBounds.x - (getFontWidth() / 2);
int southLine = yTextMidPoint;
do {
final Bookmark child = (Bookmark) e.nextElement();
final Bookmark next = getBookmark(nextItem);
if (child != next) {
break;
}
southLine = (((2 * nextItem) + 1) * getFontHeight()) / 2;
g.drawLine(xLineToChildren, southLine, textBounds.x - 2, southLine);
nextItem = paintItem(nextItem, g, child);
} while (e.hasMoreElements());
if (southLine > yTextMidPoint) {
g.drawLine(xLineToChildren, yTextMidPoint, xLineToChildren, southLine);
}
} else if (displayName != null) {
g.drawLine(textBounds.x - getFontWidth(), yTextMidPoint, textBounds.x - 2, yTextMidPoint);
}
}
return nextItem;
}