Question

我希望有一个UIProgressView来显示导航栏底部的进度（就像在iOS 7中发送iMessage或短信一样）。但是我在导航控制器的每个表视图视图中都需要这一点。所以对我来说很清楚：我必须将它添加到UINavigationController中。但问题是，不可能将UIProgressView添加到UINavigationController。所以我尝试了两件事：

第一次我尝试以编程方式将其添加到UINavigationController的视图中。但问题是定位UIProgressView并在更改设备旋转时使其看起来很好。

我尝试的第二件事是将UIProgressView添加到每个UITableView，但是我真的必须为每个视图执行此操作。它也不好看，因为它不在导航栏的顶部，而是在它下面。但是我不喜欢第二种解决方案的主要原因是因为ProgressViews带有他们的TableView，所以你没有静态的，而是改变它们。

在此之后，我不知道这样做，所以我问你......有没有人知道如何做到这一点？

它应该是这样的： enter image description here

Answer 1

我终于找到了解决方案：

我制作了一个自定义的UINavigationController并将其添加到viewDidLoad

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    progress = [[UIProgressView alloc] init];

    [[self view] addSubview:progress];

    UIView *navBar = [self navigationBar];


    [[self view] addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[navBar]-[progress(2@20)]"
                                                                        options:NSLayoutFormatDirectionLeadingToTrailing
                                                                        metrics:nil
                                                                          views:NSDictionaryOfVariableBindings(progress, navBar)]];

    [[self view] addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[progress]|"
                                                                        options:NSLayoutFormatDirectionLeadingToTrailing
                                                                        metrics:nil
                                                                          views:NSDictionaryOfVariableBindings(progress)]];

    [progress setTranslatesAutoresizingMaskIntoConstraints:NO];

    [progress setProgress:0 animated:NO];
}

我创建了一个新的UIProgressView（我在@interface中声明）添加了约束以将其定位在导航栏下方（这一步很重要:)将translatesAutoresizingMaskIntoConstraints设置为NO。< / p>

Answer 2

我重写了原始海报的答案，以便栏实际上就在导航栏内。有趣的是，当它显示时，它与一个像素底线重叠（实际上取代它），所以当你将进度条设置为隐藏时，进度条淡出并且分隔线淡入。关键部分此解决方案是将进度条添加到导航控制器的视图，而不是导航栏。

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    UIProgressView *progress = [[UIProgressView alloc] initWithProgressViewStyle:UIProgressViewStyleBar];;
    [self.view addSubview:progress];
    UINavigationBar *navBar = [self navigationBar];

#if 1
    [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[navBar]-0-[progress]"
                                                                        options:NSLayoutFormatDirectionLeadingToTrailing
                                                                        metrics:nil
                                                                          views:NSDictionaryOfVariableBindings(progress, navBar)]];

    [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[progress]|"
                                                                        options:NSLayoutFormatDirectionLeadingToTrailing
                                                                        metrics:nil
                                                                            views:NSDictionaryOfVariableBindings(progress)]];
#else
    NSLayoutConstraint *constraint;
    constraint = [NSLayoutConstraint constraintWithItem:progress attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:navBar attribute:NSLayoutAttributeBottom multiplier:1 constant:-0.5];
    [self.view addConstraint:constraint];

    constraint = [NSLayoutConstraint constraintWithItem:progress attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:navBar attribute:NSLayoutAttributeLeft multiplier:1 constant:0];
    [self.view addConstraint:constraint];

    constraint = [NSLayoutConstraint constraintWithItem:progress attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:navBar attribute:NSLayoutAttributeRight multiplier:1 constant:0];
    [self.view addConstraint:constraint];

#endif
    [progress setTranslatesAutoresizingMaskIntoConstraints:NO];
    [progress setProgress:0.5 animated:NO];
}

我不确定为什么必须在NSLayoutContstraints代码中添加0.5偏移量以获得相同的匹配，但事实确实如此。我使用的不是视觉格式，而是你的选择。请注意，与底部相反，这也使其无缝旋转。

Answer 3

基于此处已建议的内容，如果您想在应用程序的每个导航栏上显示它，您可以将其变为UINavigationController上的扩展（Swift）：

{}

更新（使用Swift 3语法）

这是一个更完整的解决方案。我把这个扩展名放在一个名为 UINavigationController + Progress.swift 的文件中。（注意我正在使用threadInfoString标记属性来查找具有可选extension UINavigationController { public override func viewDidLoad() { super.viewDidLoad() let progressView = UIProgressView(progressViewStyle: .Bar) self.view.addSubview(progressView) let navBar = self.navigationBar self.view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:[navBar]-0-[progressView]", options: .DirectionLeadingToTrailing, metrics: nil, views: ["progressView" : progressView, "navBar" : navBar])) self.view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("H:|[progressView]|", options: .DirectionLeadingToTrailing, metrics: nil, views: ["progressView" : progressView])) progressView.translatesAutoresizingMaskIntoConstraints = false progressView.setProgress(0.5, animated: false) } }属性的UIView。可能有更优雅的方法来做到这一点，但这似乎是最直接的）< / p>

UIProgressView

所以我在这里给出了一个特定的实现，假设您希望使用当前计数和总计数值来更新进度条。现在，您需要的是从执行任何用于确定进度的任务的代码发布通知 - 例如下载文件列表。这是发布通知的代码：

progressView

Answer 4

您可以在navigationController的根viewController中执行此操作：

override func viewDidLoad() {
    super.viewDidLoad()

    // if VC is pushed in a navigation controller I add a progress bar
    if let navigationVC = self.navigationController {

        // create progress bar with .bar style and add it as subview
        let progressBar = UIProgressView(progressViewStyle: .Bar)
        navigationVC.navigationBar.addSubview(self.progressView)

        // create constraints
        // NOTE: bottom constraint has 1 as constant value instead of 0; this way the progress bar will look like the one in Safari
        let bottomConstraint = NSLayoutConstraint(item: navigationVC.navigationBar, attribute: .Bottom, relatedBy: .Equal, toItem: progressBar, attribute: .Bottom, multiplier: 1, constant: 1)
        let leftConstraint = NSLayoutConstraint(item: navigationVC.navigationBar, attribute: .Leading, relatedBy: .Equal, toItem: progressBar, attribute: .Leading, multiplier: 1, constant: 0)
        let rightConstraint = NSLayoutConstraint(item: navigationVC.navigationBar, attribute: .Trailing, relatedBy: .Equal, toItem: progressBar, attribute: .Trailing, multiplier: 1, constant: 0)

        // add constraints
        progressBar.translatesAutoresizingMaskIntoConstraints = false
        navigationVC.view.addConstraints([bottomConstraint, leftConstraint, rightConstraint])
    }
}

但是如果你想要总是在导航栏中为所有推送的VC提供相同的进度条，那么最好继承UINavigationController并且：

override func viewDidLoad() {
    super.viewDidLoad()

    // create progress bar with .bar style and keep reference with a property
    let progressBar = UIProgressView(progressViewStyle: .Bar)
    self.progressBar = progressBar

    // add progressBar as subview
    self.navigationBar.addSubview(progressBar)

    // create constraints
    // NOTE: bottom constraint has 1 as constant value instead of 0; this way the progress bar will look like the one in Safari
    let bottomConstraint = NSLayoutConstraint(item: self.navigationBar, attribute: .Bottom, relatedBy: .Equal, toItem: progressBar, attribute: .Bottom, multiplier: 1, constant: 1)
    let leftConstraint = NSLayoutConstraint(item: self.navigationBar, attribute: .Leading, relatedBy: .Equal, toItem: progressBar, attribute: .Leading, multiplier: 1, constant: 0)
    let rightConstraint = NSLayoutConstraint(item: self.navigationBar, attribute: .Trailing, relatedBy: .Equal, toItem: progressBar, attribute: .Trailing, multiplier: 1, constant: 0)

    // add constraints
    progressBar.translatesAutoresizingMaskIntoConstraints = false
    self.view.addConstraints([bottomConstraint, leftConstraint, rightConstraint])  
}

Answer 5

您可以在UInavigationController的titleView中添加ProgressBar，如下面的屏幕截图所示：

UIView *customView = [[UIView alloc] initWithFrame:CGRectMake(0,0,200,30)];
[customView setBackgroundColor:[UIColor whiteColor]];

    UIProgressView *p = [[UIProgressView alloc] initWithFrame:CGRectMake(10, 20, 180,20)];    // Here pass frame as per your requirement
p.progress = 0.5f;
[customView addSubview:p];
self.navigationItem.titleView = customView;

输出： NAVIGATIONBAR WITH PROGRESSBAR

希望它对你有所帮助。

Answer 6

SnapKit个用户的解决方案。还将progressView放在navigationBar上方。

extension UINavigationController {

    public override func viewDidLoad() {
        super.viewDidLoad()

        let progressView = UIProgressView(progressViewStyle: .bar)
        self.view.addSubview(progressView)
        let navBar = self.navigationBar

        progressView.snp.makeConstraints { make in
            make.leading.trailing.equalToSuperview()
            make.top.equalTo(navBar.snp.top)
        }
        progressView.setProgress(0.5, animated: false)

        view.bringSubviewToFront(progressView)
    }
}

Answer 7

我已在我的博文here

中概述了如何执行此操作

TL; DR

创建协议，将UIProgressView呈现为UINavigationController子视图
创建更新UIProgressView
使您的UINavigationController符合演示者协议
将导航堆栈中的每个UIViewController符合更新程序协议

在UINavigationController的UINavigationBar内部或顶部显示UIProgressView

7 个答案: