swift2letgap=CGFloat(randomInRange(StackGapMinWidth...maxGap))Missingargumentlabel'range:'incallSwift3-新错误letgap=CGFloat(randomInRange(range:StackGapMinWidth...maxGap))No'...'candidatesproducetheexpectedcontextualresulttype'Range'Overloadsfor'...'existwiththeseresulttypes:ClosedRange,CountableCl