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SWIFT - UIBarButtonItem.customView重置为原始状态

uibarbuttonitem swift ios

Alex Ritter · 技术社区 · 6 年前

我有一个导航栏按钮项,它在数据查询期间添加了一个自定义活动指示器视图。当查询完成时,我想把按钮设置回到原来的状态。这是我当前的代码:

let filterActivityIndicator = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 20, height: 20))
filterActivityIndicator.color = .yandasRed
filterMenuNavButton.customView = filterActivityIndicator
filterActivityIndicator.startAnimating()
ProductsFilterData.searchShared.updateFilteredCollectionData(source: "Search") { (done) in
        filterActivityIndicator.stopAnimating()
        self.filterMenuNavButton.setBackgroundImage(#imageLiteral(resourceName: "icons8-slider-30"), for: .normal, barMetrics: .default)
}

我试过将自定义背景设置为nil,但没有任何效果。我试过重新设置条按钮项的背景图像,但没有任何效果。有什么想法吗?谢谢!

编辑: 我要操作的uibarbuttonem在右边,但是右边有两个按钮项。 filterMenuNavButton 是我试图操作的特定按钮的IBoutlet。

2 回复 | 直到 6 年前

Matic Oblak 6 年前

有时失效是个问题。似乎您需要再次将按钮设置到导航栏。它是如此聪明,你首先需要设置它 nil 甚至会产生效果。

这就是我试过的:

let buttonImage: UIImage = #imageLiteral(resourceName: "icons8-slider-30")

let filterMenuNavButton = UIBarButtonItem(image: buttonImage, style: .plain, target: nil, action: nil)
self.navigationItem.rightBarButtonItem = filterMenuNavButton

DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
    let filterActivityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .gray)
    filterMenuNavButton.customView = filterActivityIndicator
    filterActivityIndicator.startAnimating()
    DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
        filterActivityIndicator.stopAnimating()
        filterMenuNavButton.customView = nil
        filterMenuNavButton.setBackgroundImage(buttonImage, for: .normal, barMetrics: .default)
        self.navigationItem.rightBarButtonItem = nil
        self.navigationItem.rightBarButtonItem = filterMenuNavButton
    }
}

我不确定你的设置是什么,但是我用了一个简单的导航视图控制器并把这个代码放进去。 viewDidLoad 它的当前(根)视图控制器。

最后一部分可能是你想要的,你需要:

设置自定义视图以清除
添加图像或更改其他按钮属性
清除按钮项(设置为零)
将按钮项设置回所需项

我希望这能解决你的问题。不过,我必须说,在指示器运行时创建一个新的按钮项可能更有意义。检查以下各项:

DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
    let preservedButtonItem = self.navigationItem.rightBarButtonItem

    let filterActivityIndicator: UIActivityIndicatorView = {
        let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .gray)
        self.navigationItem.rightBarButtonItem = UIBarButtonItem(customView: activityIndicator)
        return activityIndicator
    }()

    filterActivityIndicator.startAnimating()
    DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
        filterActivityIndicator.stopAnimating()
        self.navigationItem.rightBarButtonItem = preservedButtonItem
    }
}

编辑:多个按钮

对于多个按钮,情况应该非常相似。请尝试玩以下游戏:

guard let oldItems = navigationItem.rightBarButtonItems else {
    return
}

var newItems = oldItems

// Find the index of item so we may ereplace it
guard let index = newItems.index(where: { $0 === filterMenuNavButton }) else {
    return
}
let activityIndicator: UIActivityIndicatorView = {
    let activity = UIActivityIndicatorView()
    return activity
}()
newItems[index] = UIBarButtonItem(customView: activityIndicator)

navigationItem.rightBarButtonItems = newItems
DispatchQueue.main.asyncAfter(deadline: .now()+2.0) {
    self.navigationItem.rightBarButtonItems = oldItems
}

gadu 6 年前

使用“自定义视图”作为“条形图”按钮项执行此操作没有问题:

fileprivate var underlyingButton: UIButton?

...

let barButton = UIButton(type: .custom)
barButton.addTarget(self, action: #selector(stuffs), for: .touchUpInside)
barButton.setImage(image, for: UIControlState())

let rightItem = UIBarButtonItem(customView: barButton)
self.filterMenuNavButton = rightItem

self.underlyingButton = barButton

然后我可以打电话给你简单的做:

guard let button = underlyingButton else {
    return
}
button.setImage(someOtherImage, for: UIControlState())