if (this.topBlock != null) {
            RectangleConstraint c1 = new RectangleConstraint(w[0], null,
                    LengthConstraintType.FIXED, 0.0,
                    new Range(0.0, constraint.getHeight()),
                    LengthConstraintType.RANGE);
            Size2D size = this.topBlock.arrange(g2, c1);
            h[0] = size.height;