Device Activity Center监控无法停止，屏蔽应用无法解锁求助

核心问题点 #

1. ManagedSettingsStore实例不共享：BlockManager和Monitor各自初始化了独立的ManagedSettingsStore，导致Monitor中修改的屏蔽设置无法覆盖BlockManager中设置的状态，解锁操作无效。
2. DeviceActivitySchedule区间配置错误：当前schedule的intervalStart设为当天0点，而非计时器启动的当前时间，导致监控区间逻辑不符合预期，intervalDidEnd可能无法正确触发。
3. 停止监控的方法调用不精确：stopMonitoring()中未指定要停止的具体活动名称，可能无法彻底终止目标监控任务。

修复后的代码 #

BlockManager修改 #

import Foundation
import FamilyControls
import DeviceActivity
import ManagedSettings

class BlockManager: ObservableObject {
    static let shared = BlockManager()
    // 共享同一个ManagedSettingsStore实例
    let store = ManagedSettingsStore()

    private init() {}

    var selectionToDiscourage = FamilyActivitySelection() {
        willSet {
            let applications = newValue.applicationTokens
            let categories = newValue.categoryTokens
            store.shield.applications = applications.isEmpty ? nil : applications
            store.shield.applicationCategories = categories.isEmpty ? nil : ShieldSettings.ActivityCategoryPolicy.specific(categories, except: Set())
            store.shield.webDomainCategories = categories.isEmpty ? nil : ShieldSettings.ActivityCategoryPolicy.specific(categories, except: Set())
        }
    }

    func initiateMonitoring(timeInterval: TimeInterval) {
        let start = Date()
        let end = start.addingTimeInterval(timeInterval)
        // 正确设置监控区间：从当前时间开始到结束时间
        let startComponents = Calendar.current.dateComponents([.year, .month, .day, .hour, .minute], from: start)
        let endComponents = Calendar.current.dateComponents([.year, .month, .day, .hour, .minute], from: end)
        
        let schedule = DeviceActivitySchedule(
            intervalStart: startComponents,
            intervalEnd: endComponents,
            repeats: false,
            warningTime: nil
        )

        let center = DeviceActivityCenter()
        do {
            try center.startMonitoring(.once, during: schedule)
        } catch {
            print("Could not start monitoring \(error)")
        }
    }
    
    func stopMonitoring() {
        let center = DeviceActivityCenter()
        // 指定停止具体的活动名称，确保彻底终止监控
        center.stopMonitoring(.once)
        // 主动重置屏蔽设置，确保解锁
        resetShieldSettings()
    }
    
    // 新增方法：统一重置所有屏蔽设置
    func resetShieldSettings() {
        store.shield.applications = nil
        store.shield.applicationCategories = nil
        store.shield.webDomainCategories = nil
        store.shield.webDomains = nil
    }
}

extension DeviceActivityName {
    static let once = Self("once")
}

Monitor修改 #

import MobileCoreServices
import ManagedSettings
import DeviceActivity

class Monitor: DeviceActivityMonitor {
    // 使用BlockManager共享的store实例，而非重新创建
    private let store = BlockManager.shared.store
    
    override func intervalDidStart(for activity: DeviceActivityName) {
        super.intervalDidStart(for: activity)
        let model = BlockManager.shared
        let applications = model.selectionToDiscourage.applicationTokens
        store.shield.applications = applications.isEmpty ? nil : applications
        print("start monitoring")
    }

    override func intervalDidEnd(for activity: DeviceActivityName) {
        super.intervalDidEnd(for: activity)
        // 调用统一的重置方法，确保所有屏蔽设置被清除
        BlockManager.shared.resetShieldSettings()
        print("end monitoring, shield reset")
    }
    
    override func eventDidReachThreshold(_ event: DeviceActivityEvent.Name, activity: DeviceActivityName) {
        super.eventDidReachThreshold(event, activity: activity)
        BlockManager.shared.resetShieldSettings()
    }
}

额外注意事项 #

• 确保在AppDelegate或SceneDelegate中正确注册Monitor：

  func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
      DeviceActivityCenter.shared.monitor = Monitor()
      return true
  }
  

• 测试时需确保应用已获得Screen Time权限，否则所有屏蔽操作无效。

内容的提问来源于stack exchange，提问作者Lorenzo Vecchio