objective c - 同時訪問0x1c0a7f0f8,但修改需要Xcode 9 beta 4上的獨占訪問錯誤




objective-c crash (2)

我的項目使用Objective-C和Swift代碼。 當用戶登錄時,它會調用一組用於用戶首選項的apis,我有一個DataCoordinator.swift類來調度API操作,我從UserDetailViewController.m類調用此調用來加載用戶首選項。 在我使用Xcode 9 beta 4將我的代碼遷移到Swift 4之前,這種用法工作正常。現在,當我通過在DataCoordinator類中給我這個錯誤登錄時,它崩潰了。 以下是我的DataCoordinator和Viewcontroller類的示例。

DataCoordinator.swift

import UIKit

@objcMembers

class DataCoordinator: NSObject {

    //MARK:- Private
    fileprivate var user = myDataStore.sharedInstance().user
    fileprivate var preferenceFetchOperations = [FetchOperation]()

    fileprivate func scheduleFetchOperation(_ operation:FetchOperation, inFetchOperations operations:inout [FetchOperation]) {
        guard  operations.index(of: operation) == nil else { return }
        operations.append(operation)
    }

    fileprivate func completeFetchOperation(_ fetchOperation:FetchOperation, withError error:Error?, andCompletionHandler handler:@escaping FetchCompletionHandler) {

        func removeOperation(_ operation:FetchOperation, fromOperations operations:inout [FetchOperation]) {
            if operations.count > 0 {
                operations.remove(at: operations.index(of: fetchOperation)!)                 
              handler(error)
            }
        }

        if preferenceFetchOperations.contains(fetchOperation) {
            removeOperation(fetchOperation, fromOperations: &preferenceFetchOperations)
        }

    }

    fileprivate func schedulePreferencesFetchOperation(_ serviceName:String, fetch:@escaping FetchOperationBlock){
        let operation = FetchOperation(name: serviceName, fetch: fetch);
        scheduleFetchOperation(operation, inFetchOperations: &preferenceFetchOperations)
    }


    fileprivate func runOperationsIn(_ fetchOperations:inout [FetchOperation]) {
        for  var operation in fetchOperations {
            guard operation.isActivated == false else { continue }
            operation.isActivated = true
            operation.execute()
        }
    }


    //MARK:- Non-Private
    typealias FetchCompletionHandler = (_ error:Error?)->Void

    var numberOfPreferencesFetchCalls:Int {
        get { return preferenceFetchOperations.count }
    }


    // MARK: -
    func fetchPreferences(_ completionHandler:@escaping FetchCompletionHandler) -> Void {
        defer {
            runOperationsIn(&preferenceFetchOperations)
        }

        schedulePreferencesFetchOperation("com.fetchPreferences.type1") {[unowned self] (operation:FetchOperation) in
            WebServiceManager.getType1Detail(for: user) {[unowned self] (error) in
                self.completeFetchOperation(operation,  withError: error, andCompletionHandler: completionHandler)
            }

        }

        schedulePreferencesFetchOperation("com.fetchPreferences.type2") {[unowned self] (operation:FetchOperation) in
            WebServiceManager.getType2Detail(for: user) {[unowned self] (error) in
                self.completeFetchOperation(operation,  withError: error, andCompletionHandler: completionHandler)
            }

        }

        schedulePreferencesFetchOperation("com.fetchPreferences.type3") {[unowned self] (operation:FetchOperation) in
            WebServiceManager.getType3Detail(for: user) {[unowned self] (error) in
                self.completeFetchOperation(operation,  withError: error, andCompletionHandler: completionHandler)
            }

        }

        schedulePreferencesFetchOperation("com.fetchPreferences.type4") {[unowned self] (operation:FetchOperation) in
            WebServiceManager.getType4Detail(for: user) {[unowned self] (error) in
                self.completeFetchOperation(operation,  withError: error, andCompletionHandler: completionHandler)
            }

        }
    }

}


// MARK:- Fetch Operation Struct
private typealias FetchOperationBlock = (_ operation:FetchOperation)->Void

private struct FetchOperation:Hashable {
    fileprivate var runToken = 0
    fileprivate let fetchBlock:FetchOperationBlock

    let name:String!
    var isActivated:Bool {
        get {
            return runToken == 0 ? false : true
        }

        mutating set {
            if runToken == 0 && newValue == true {
                runToken = 1
            }
        }
    }

    fileprivate var hashValue: Int {
        get {
            return name.hashValue
        }
    }

    func execute() -> Void {
        fetchBlock(self)
    }

    init (name:String, fetch:@escaping FetchOperationBlock) {
        self.name = name
        self.fetchBlock = fetch
    }
}
private func ==(lhs: FetchOperation, rhs: FetchOperation) -> Bool {
    return lhs.hashValue == rhs.hashValue
}

//這是我在我的viewcontrollers viewDidLoad方法中調用它的方法

__weak UserDetailViewController *weakSelf = self;
[self.dataCoordinator fetchPreferences:^(NSError * _Nullable error) {
                if (error == nil) {
                    [weakSelf didFetchPrefrences];
                }
                else {
                    // handle error
                }
            }];

//completion response
- (void)didFetchPrefrences {

    //when api calls complete load data
    if (self.dataCoordinator.numberOfPreferencesFetchCalls == 0) {

        //Load details

     }

}

我不確定如何繼續,我在https://bugs.swift.org/browse/SR-5119看到了一個錯誤報告,但它似乎在Xcode 9 beta 3中得到修復。


Swift 4:如果你在observeValue方法中檢查你的上下文,只要讓你的上下文變量是靜態的。 這篇博文詳細描述了這個問題。


就我而言,Swift 4實際上發現了一種在我從多個地方開始調用函數之前不會注意到的錯誤。 我的函數被傳入一個inout全局數組,它引用了這個參數和全局名。 當我改變功能只參考參數,“同時訪問”錯誤消失了。





xcode9-beta