private void updateForDragOver(Point where) {
		int count = getComponentCount();
		int insertAt = count;
		for (int i = 0; i < count; i++) {
			Component child = getComponent(i);
			if (child instanceof DockTab) {
				Rectangle bounds = child.getBounds();
				if (where.x < bounds.x + bounds.width / 2) {
					insertAt = i;
					break;
				}
				if (where.x < bounds.x + bounds.width) {
					insertAt = i + 1;
					break;
				}
			} else {
				insertAt = i;
				break;
			}
		}
		if (insertAt != mDragInsertIndex) {
			mDragInsertIndex = insertAt;
			repaint();
		}
	}