所以我想在导航控制器的导航栏中添加标题下的“副标题”。
到目前为止,我查找的大部分内容都要我使用CGRect。我不知道那是什么,这听起来像是想要我创建一个全新的视图而不是我想做的事情。
我的问题是,有一种点方法可以轻松添加字幕视图吗?
我发现的最接近的事情是在堆栈溢出时发布,这是链接:
Create a subtitle in navigationbar
显然去年这个工作但现在我得到错误,它在我的viewDidLoad ...
我试过这个:
self.navigationController?.navigationItem.prompt =“Subtitle Here”
这是唯一不会显示任何错误但仍然不起作用的东西。它实际上什么都不做。在运行时至少没有任何可见的东西。
另一方面,swift是首选。谢谢!
虽然有一个解决方案,但它有一些已知的问题
解决方案是编写这样的函数
func setTitle(title:String, subtitle:String) -> UIView {
let titleLabel = UILabel(frame: CGRectMake(0, -2, 0, 0))
titleLabel.backgroundColor = UIColor.clearColor()
titleLabel.textColor = UIColor.grayColor()
titleLabel.font = UIFont.boldSystemFontOfSize(17)
titleLabel.text = title
titleLabel.sizeToFit()
let subtitleLabel = UILabel(frame: CGRectMake(0, 18, 0, 0))
subtitleLabel.backgroundColor = UIColor.clearColor()
subtitleLabel.textColor = UIColor.blackColor()
subtitleLabel.font = UIFont.systemFontOfSize(12)
subtitleLabel.text = subtitle
subtitleLabel.sizeToFit()
let titleView = UIView(frame: CGRectMake(0, 0, max(titleLabel.frame.size.width, subtitleLabel.frame.size.width), 30))
titleView.addSubview(titleLabel)
titleView.addSubview(subtitleLabel)
let widthDiff = subtitleLabel.frame.size.width - titleLabel.frame.size.width
if widthDiff < 0 {
let newX = widthDiff / 2
subtitleLabel.frame.origin.x = abs(newX)
} else {
let newX = widthDiff / 2
titleLabel.frame.origin.x = newX
}
return titleView
}
在viewDidLoad
中使用此功能进行自定义导航标题视图
self.navigationItem.titleView = setTitle("Title", subtitle: "SubTitle")
唯一已知的问题是如果字幕变得非常大,则发生错位。
资料来源:https://gist.github.com/nazywamsiepawel/0166e8a71d74e96c7898
这是我的版本在扩展上使用堆栈视图。
extension UINavigationItem {
func setTitle(title:String, subtitle:String) {
let one = UILabel()
one.text = title
one.font = UIFont.systemFont(ofSize: 17)
one.sizeToFit()
let two = UILabel()
two.text = subtitle
two.font = UIFont.systemFont(ofSize: 12)
two.textAlignment = .center
two.sizeToFit()
let stackView = UIStackView(arrangedSubviews: [one, two])
stackView.distribution = .equalCentering
stackView.axis = .vertical
stackView.alignment = .center
let width = max(one.frame.size.width, two.frame.size.width)
stackView.frame = CGRect(x: 0, y: 0, width: width, height: 35)
one.sizeToFit()
two.sizeToFit()
self.titleView = stackView
}
}
非常感谢您的回答! @RajanMaheshwari
除了使用widthDiff创建的if语句之外,您的编码工作正常。
我调整了一点,一切顺利。
if widthDiff < 0 {
let newX = widthDiff / 2
subtitleLabel.frame.origin.x = abs(newX)
} else {
let newX = widthDiff / 2
titleLabel.frame.origin.x = newX
}
再次感谢您的回复!
@ iosjillian的Swift 4扩展程序运行良好,增加了一点来纪念栏的外观和用户字体首选项:
import UIKit
extension UINavigationItem {
func setTitle(_ title: String, subtitle: String) {
let appearance = UINavigationBar.appearance()
let textColor = appearance.titleTextAttributes?[NSAttributedString.Key.foregroundColor] as? UIColor ?? .black
let titleLabel = UILabel()
titleLabel.text = title
titleLabel.font = .preferredFont(forTextStyle: UIFont.TextStyle.headline)
titleLabel.textColor = textColor
let subtitleLabel = UILabel()
subtitleLabel.text = subtitle
subtitleLabel.font = .preferredFont(forTextStyle: UIFont.TextStyle.subheadline)
subtitleLabel.textColor = textColor.withAlphaComponent(0.75)
let stackView = UIStackView(arrangedSubviews: [titleLabel, subtitleLabel])
stackView.distribution = .equalCentering
stackView.alignment = .center
stackView.axis = .vertical
self.titleView = stackView
}
}
如果有人在寻找上述解决方案的Objective-C
代码:
UILabel *title = [[UILabel alloc]init];
UILabel *subtitle = [[UILabel alloc]init];
[title setFont:[UIFont systemFontOfSize:12]];
[title setTextColor:[UIColor whiteColor]];
[title setFont:[UIFont systemFontOfSize:17]];
[title sizeToFit];
title.text = @"Title";
[subtitle setTextColor:[UIColor whiteColor]];
[subtitle setFont:[UIFont systemFontOfSize:12]];
[subtitle setTextAlignment:NSTextAlignmentCenter];
[subtitle sizeToFit];
subtitle.text = @"Subtitle Title";
UIStackView *stackVw = [[UIStackView alloc]initWithArrangedSubviews:@[title,subtitle]];
stackVw.distribution = UIStackViewDistributionEqualCentering;
stackVw.axis = UILayoutConstraintAxisVertical;
stackVw.alignment =UIStackViewAlignmentCenter;
[stackVw setFrame:CGRectMake(0, 0, MAX(title.frame.size.width, subtitle.frame.size.width), 35)];
self.navigationItem.titleView = stackVw;
谢谢@RajanMaheshwari的答案
如果有任何人在副标题文本长于标题文本时出现标题未对齐的问题,我将以下代码添加到Rajan的答案中,正好在下面实例化subtitleLabel的地方:
// Fix incorrect width bug
if (subtitleLabel.frame.size.width > titleLabel.frame.size.width) {
var titleFrame = titleLabel.frame
titleFrame.size.width = subtitleLabel.frame.size.width
titleLabel.frame = titleFrame
titleLabel.textAlignment = .center
}
希望这可以帮助遇到与我相同问题的人
斯威夫特4:
import UIKit
class NavigationTitleView: UIView {
private var contentStackView = UIStackView()
private var titleLabel = UILabel()
private var subTitleLabel = UILabel()
override init(frame: CGRect) {
super.init(frame: frame)
viewConfig()
addViewsConfig()
layoutViewsConfig()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func set(title: String, subTitle: String){
self.titleLabel.text = title
self.subTitleLabel.text = subTitle
}
private func viewConfig() {
contentStackView.axis = .vertical
contentStackView.alignment = .center
contentStackView.distribution = .fill
contentStackView.spacing = 5
self.backgroundColor = .clear
self.titleLabel.textColor = .white
self.self.subTitleLabel.textColor = .white
}
private func addViewsConfig() {
contentStackView.addArrangedSubview(subTitleLabel)
contentStackView.addArrangedSubview(titleLabel)
self.addSubview(contentStackView)
}
private func layoutViewsConfig(){
contentStackView.translatesAutoresizingMaskIntoConstraints = false
contentStackView.centerXAnchor.constraint(equalTo: self.centerXAnchor, constant: 0.0).isActive = true
contentStackView.centerYAnchor.constraint(equalTo: self.centerYAnchor, constant: 0.0).isActive = true
}
}
使用:
import UIKit
class ViewController: UIViewController {
private var navigationTitleView = NavigationTitleView()
override func viewDidLoad() {
super.viewDidLoad()
self.navigationItem.titleView = navigationTitleView
navigationTitleView.set(title: "title", subTitle: "subTitle")
}
}
另一种解决方案,仅使用一个标签和NSAttributedString
来区分标题和副标题(具有不同的字体大小,重量,颜色等)。消除了不同标签对齐的问题。
extension UIViewController {
func setTitle(_ title: String, subtitle: String) {
let rect = CGRect(x: 0, y: 0, width: 400, height: 50)
let titleSize: CGFloat = 20 // adjust as needed
let subtitleSize: CGFloat = 15
let label = UILabel(frame: rect)
label.backgroundColor = .clear
label.numberOfLines = 2
label.textAlignment = .center
label.textColor = .black
let text = NSMutableAttributedString()
text.append(NSAttributedString(string: title, attributes: [.font : UIFont.boldSystemFont(ofSize: titleSize)]))
text.append(NSAttributedString(string: "\n\(subtitle)", attributes: [.font : UIFont.systemFont(ofSize: subtitleSize)]))
label.attributedText = text
self.navigationItem.titleView = label
}
}
自定义titleView部分基于https://stackoverflow.com/a/34298491/3918865
我真的很喜欢@ user2325031的答案,但发现不需要调整标签大小以适应和设置框架。我还根据@ GerardoMR的建议将stackView的对齐设置为.center。
extension UINavigationItem {
func setTitle(_ title: String, subtitle: String) {
let titleLabel = UILabel()
titleLabel.text = title
titleLabel.font = .systemFont(ofSize: 17.0)
titleLabel.textColor = .black
let subtitleLabel = UILabel()
subtitleLabel.text = subtitle
subtitleLabel.font = .systemFont(ofSize: 12.0)
subtitleLabel.textColor = .gray
let stackView = UIStackView(arrangedSubviews: [titleLabel, subtitleLabel])
stackView.distribution = .equalCentering
stackView.alignment = .center
stackView.axis = .vertical
self.titleView = stackView
}
}