Patent ID: 8228685

Claim:
A handheld electronic device, comprising: a first casing having a first upper surface and a first lateral surface perpendicular to said first upper surface, and comprising: plural operating buttons disposed on said first upper surface; and a fire button disposed in said first upper surface, wherein said fire button is not protruded over the first casing; and a second casing having a second upper surface and a second lower surface parallel with said second upper surface, wherein said second casing is connected with said first casing, said second lower surface is in contact with said first upper surface, and said second casing is slidable with respect to said first casing, and said second casing comprises: a screen disposed on said second upper surface for displaying an operating frame; an opening formed in said second lower surface; an auxiliary button comprising a rotating shaft and a triggering part, wherein said rotating shaft is inserted within said second casing, and said auxiliary button is rotatable with respect to said second casing via said rotating shaft; and a receiving part disposed within said second casing for sheltering said opening and accommodating said auxiliary button, wherein when said first casing is completely covered by said second casing, said auxiliary button is stored within said receiving part, wherein when said second casing is slid with respect to said first casing and said plural operating buttons are exposed outside said first upper surface, said opening is exposed outside said second lower surface, and said auxiliary button is rotated with respect to said second casing and penetrated through said opening, so that said triggering part of said auxiliary button is moved to said first lateral surface and contacted with said fire button.