videoFps property Null safety

Field description: video capturing frame rate

Recommended value: 15 or 20 fps. If the frame rate is lower than 5 fps, there will be obvious lagging; if lower than 10 fps but higher than 5 fps, there will be slight lagging; if higher than 20 fps, too many resources will be wasted (the frame rate of movies is generally 24 fps).

Note: the front cameras on many Android phones do not support a capturing frame rate higher than 15 fps. For some Android phones that focus too much on beautification features, the capturing frame rate of the front cameras may be lower than 10 fps.