Method mouseup

src/elements/slider.rs:227–232

(&self, e: &mut MouseEvent)

    }

    fn mouseup(&self, e: &mut MouseEvent) {
        self.state.borrow_mut().dragging = false;
        self.uncapture();

        // self.base.mouseup(e);
    }

    fn node(&self) -> Option<Node> {
        Some(self.node)