如何获取HKWorkout的totalDistance

import HealthKit

// 检查设备是否支持HealthKit
guard HKHealthStore.isHealthDataAvailable() else {
    print("设备不支持HealthKit")
    return
}

// 创建HKHealthStore实例
let healthStore = HKHealthStore()

// 请求授权访问健康数据
let workoutType = HKObjectType.workoutType()
let readTypes: Set<HKObjectType> = [workoutType]
healthStore.requestAuthorization(toShare: nil, read: readTypes) { (success, error) in
    if let error = error {
        print("授权失败：\(error.localizedDescription)")
        return
    }
    
    if success {
        // 创建查询对象
        let sampleType = HKObjectType.workoutType()
        let predicate = HKQuery.predicateForSamples(withStart: Date.distantPast, end: Date(), options: .strictStartDate)
        let sortDescriptor = NSSortDescriptor(key: HKSampleSortIdentifierStartDate, ascending: false)
        let query = HKSampleQuery(sampleType: sampleType, predicate: predicate, limit: HKObjectQueryNoLimit, sortDescriptors: [sortDescriptor]) { (query, results, error) in
            if let error = error {
                print("查询失败：\(error.localizedDescription)")
                return
            }
            
            if let workouts = results as? [HKWorkout] {
                for workout in workouts {
                    let totalDistance = workout.totalDistance?.doubleValue(for: HKUnit.meter())
                    print("总距离：\(totalDistance ?? 0) 米")
                }
            }
        }
        
        // 执行查询
        healthStore.execute(query)
    }
}