小编God*_*her的帖子

我想迭代一个数组数组,以便搜索特定的项目,如果退出则返回true.

var fruits = ["apple", "banana"]
var names = ["ivan", "john", "maria"]
var mainArray = [fruits, names]

// i want to return true if theres a name/fruit that is "john"
func search() -> Bool {
    for object in mainArray {
        if (object.filter { $0 == "john" }).count > 0 {
           return true
        }
    }
    return false
}


search()

这有效,但有一个较短的版本使用.map并避免在mainArray中的对象？像mainArray.map.filter ...？

是否可以像使用一样在单独的 var 中提取工具栏内容@ViewBuilder？

我想提取它并设置 .toolBar(content: myToolBarContent)

var body: some View {
    NavigationView {
        List {
        }
        .toolbar(content: {
            ToolbarItem(placement: .principal) {
                Text("Hi")
            }
            ToolbarItem(placement: .navigationBarTrailing) {
                Text("Ho")
            }
        })
    }
}

我有这个代码:

@implementation MyScene {
SKAction *delayAction; 
}
Inside a method:

delayAction = [SKAction waitForDuration:3.0];
[self runAction:[SKAction repeatActionForever: [SKAction sequence:
                                                @[delayAction, [SKAction ...]]]]]
                                                  withKey:@"myKey"];

然后我想减少加班时间.(此方法在更新时调用:)所以我试过:

    - (void)updateVelocity
{
    NSLog(@"duration:%f",delayAction.duration);
    delayAction.duration = delayAction.duration - 0.001;
}

我得到:

2014-04-04 11:45:05.781 FlyFish[5409:60b] duration:1.300000
2014-04-04 11:45:05.785 FlyFish[5409:60b] duration:1.299000
2014-04-04 11:45:05.800 FlyFish[5409:60b] duration:1.298000
2014-04-04 11:45:05.816 FlyFish[5409:60b] duration:1.297000

这似乎很好,但我的[SKAction ...]仍然在3秒后继续重复.

当我为headerView设置背景颜色时,滚动指示器位于它后面,看起来非常奇怪.我在这里创建了一个示例项目,但它基本上是一个简单的项目,其中collectionView为带有背景的标题注册了一个suplementaryView.

我以编程方式创建视图，但无法开始setContentHuggingPriority工作。这是当前结果：

private lazy var stackView: UIStackView = {
    let stackView = UIStackView()
    stackView.axis = .horizontal
    [button, text].forEach(stackView.addArrangedSubview)
    return stackView
}()

private lazy var button: UIButton = {
    let button = UIButton()
    button.setImage(Asset.configIcon.image, for: .normal)
    button.translatesAutoresizingMaskIntoConstraints = false
    button.setContentHuggingPriority(.defaultHigh, for: .horizontal)
    button.backgroundColor = .red
    return button
}()

private lazy var text: UILabel = {
    let label = UILabel()
    label.text = "This line should have more width than the button"
    label.numberOfLines = 0
    label.translatesAutoresizingMaskIntoConstraints = false
    label.setContentHuggingPriority(.defaultLow, for: .horizontal)
    return …

当我在订阅之前添加toArray()时,我得不到回调.

    googleCalendarUseCase.getEventsFromCalendars(calendars: selectedCalendars).subscribe(onNext: { (event) in
        print(event.summary) //print thousands of elements
    }).addDisposableTo(disposeBag)
    googleCalendarUseCase.getEventsFromCalendars(calendars: selectedCalendars).toArray().subscribe(onNext: { (events) in
        print(events.count)  // Never gets called
    }).addDisposableTo(disposeBag)

也许问题是函数getEventsFromCalendar但不确定为什么它工作如果我不做toArray():

func getEventsFromCalendars(calendars: [GoogleCalendar.Calendar], nextPageToken: String? = nil) -> Observable<GoogleCalendar.Event> {
    return Observable<GoogleCalendar.Event>.create { observer -> Disposable in
        var parameters: [String: Any] = [:]
        if let nextPageToken = nextPageToken {
            parameters["pageToken"] = nextPageToken
        }
        _ = self.oauthswift.client.get(GoogleCalendarAPI.events, parameters: parameters, success: { (data, response) in
            if let json = try? JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions.allowFragments) as? [String: AnyObject] { …

我给 UIViewController 添加了一个扩展来添加一个关闭按钮

    extension UIViewController {
      func addCloseButton() {
            let button = UIBarButtonItem(image: #imageLiteral(resourceName: "bar_close"), 
                                         landscapeImagePhone: nil,
                                         style: .done,
                                         target: self, 
                                         action: #selector(UIViewController.dismiss(animated:completion:)))
            navigationItem.leftBarButtonItem = button
      }
    } 

当我点击栏按钮时，我会直接崩溃到 AppDelegate。任何提示？似乎与选择器有关。