toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (currentExperiencePoints != null)
'currentExperiencePoints': currentExperiencePoints!,
if (currentLevel != null) 'currentLevel': currentLevel!,
if (lastLevelUpTimestampMillis != null)
'lastLevelUpTimestampMillis': lastLevelUpTimestampMillis!,
if (nextLevel != null) 'nextLevel': nextLevel!,
};