Waterproof button module and electronic device

An electronic device comprising:

• a housing comprising a through hole;
• an inner frame disposed in the housing and comprising an abutting portion and a retaining portion, wherein the abutting portion corresponds to the through hole, and the retaining portion is farther from the through hole than the abutting portion;
• and
• a waterproof button module comprising a pressing element, a circuit board, an adhesive layer, and an elastic layer stacking in said sequence, wherein the adhesive layer is attached to the circuit board and the elastic layer;
• wherein the pressing element comprises a fingerprint-recognition element and a frame, the fingerprint-recognition element is disposed in the frame and electrically connected to the circuit board, and the circuit board and the adhesive layer are outside of the frame;
• wherein the adhesive layer comprises a first opening and the elastic layer comprises a second opening, the first opening is aligned with the second opening and exposes a part of a rear surface of the circuit board, and the adhesive layer has an annular zone adjacent to and surrounding the first opening, and directly contacting the circuit board;
• wherein the waterproof button module further comprises an electric-connection assembly and a switch, the electric-connection assembly is electrically connected to the circuit board, and passes through the first opening and the second opening, and the switch is electrically connected to the circuit board,
• wherein the pressing element passes through the through hole, the switch abuts against the abutting portion, and an outer edge of the elastic layer of the waterproof button module is fixed on the retaining portion by waterproof glue, so that the pressing element is moveable relative to the inner frame via the elastic layer,
• wherein the electric-connection assembly comprises a first connector separated from the switch, the first connector and the switch are inside the first opening and the second opening, and are affixed to the circuit board.