What is the test for determining the validity of a local ordinance requiring the registration of firearms within a city?

At issue in Galvan v. Superior Court, supra, 70 Cal.2d 851, 76 Cal.Rptr. 642, 452 P.2d 930, was the validity of a local ordinance requiring registration of firearms within the city. At the time, although the state had enacted numerous statutes involving weapons, it had left substantial areas unregulated. The court detected no "patterned approach" to weapons control, and concluded that the state did not show a general scheme for the regulation of the subject of gun registration. (Id., at pp. 862-863, 76 Cal.Rptr. 642, 452 P.2d 930.)

Similarly, in Bell v. City of Mountain View, supra, 66 Cal.App.3d 332, 136 Cal.Rptr. 8, the court rejected an argument that the state had fully occupied the field of ambulance licensing so as to invalidate a city's licensing ordinance. The court noted that the state's licensing scheme did not include ambulances used for non-emergency purposes, and did not regulate other areas of the ambulance business, such as rates, advertising, or distribution of services. (Id., at p. 338, 136 Cal.Rptr. 8.)