if (attributeValue != null) {
Rectangle rect = new Rectangle(x, trackRectangle.y, AttributeHeaderPanel.ATTRIBUTE_COLUMN_WIDTH,
trackRectangle.height);
graphics.setColor(AttributeManager.getInstance().getColor(key, attributeValue));
graphics.fill(rect);
mouseRegions.add(new MouseableRegion(rect, key, attributeValue));
// Border
// graphics.setColor(Color.lightGray);
// graphics.fillRect(x + AttributeHeaderPanel.ATTRIBUTE_COLUMN_WIDTH, trackRectangle.y,
// AttributeHeaderPanel.COLUMN_BORDER_WIDTH, trackRectangle.height);