Diabetes has long been a chronic metabolic disorder and the growing diabetes population makes the medical care more important. In our research, we investigate a portable, non-invasive contact lens as an ideal vehicle for tear fluid with continuous detector. The key feature of our research is the reversible covalent interaction of boronic acid and saccharides such as glucose, which can further provide continuous sensing as a reusable device. Herein, we reported a hydrogel containing polymers with phenylboronic aicd (PBA) exhibit a swelling/shrinking effect, thus perform a different thickness of contact lenses. Moreover, PBA-glucose complex is reversible, making it possible for hydrogel to generate different osmotic pressure for continuous sensing.