标题为 UIImage 的导航栏

Question

我想通过使用徽标图像作为导航栏的标题而不是纯文本来自定义我的应用程序的外观。 当我使用此代码时

let logo = UIImage(named: "logo.png")
self.navigationItem.titleView = logo;

我收到错误“UIImage 无法转换为 UIView”。 我怎样才能正确地做到这一点？

Answer 1

把它放在一个UIImageView里面

let logo = UIImage(named: "logo.png")
let imageView = UIImageView(image:logo)
self.navigationItem.titleView = imageView

Answer 2

我用这个。 它适用于 iOS 8

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    let image = UIImage(named: "YOURIMAGE")
    navigationItem.titleView = UIImageView(image: image)
}

这是一个如何使用 CGRect 实现的示例。

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 38, height: 38))
    imageView.contentMode = .ScaleAspectFit
    let image = UIImage(named: "YOURIMAGE")
    imageView.image = image
    navigationItem.titleView = imageView
}

希望这会有所帮助。

Answer 3

对于 swift 4，您可以调整 imageView 大小

 let logoContainer = UIView(frame: CGRect(x: 0, y: 0, width: 270, height: 30))

 let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 270, height: 30))
 imageView.contentMode = .scaleAspectFit
 let image = UIImage(named: "your_image")
 imageView.image = image
 logoContainer.addSubview(imageView)
 navigationItem.titleView = logoContainer

Answer 4

我尝试了上面@Jack 的回答，确实出现了徽标，但是图像占据了整个导航栏。 我想让它合身。

斯威夫特 4，Xcode 9.2

1.赋值给导航控制器，UIImage。 通过分割帧和图像大小来调整大小。

func addNavBarImage() {

        let navController = navigationController!

        let image = UIImage(named: "logo-signIn6.png") //Your logo url here
        let imageView = UIImageView(image: image)

        let bannerWidth = navController.navigationBar.frame.size.width
        let bannerHeight = navController.navigationBar.frame.size.height

        let bannerX = bannerWidth / 2 - (image?.size.width)! / 2
        let bannerY = bannerHeight / 2 - (image?.size.height)! / 2

        imageView.frame = CGRect(x: bannerX, y: bannerY, width: bannerWidth, height: bannerHeight)
        imageView.contentMode = .scaleAspectFit

        navigationItem.titleView = imageView
    }

2. 在viewDidLoad()下添加函数

    addNavBarImage()

注意图像资产。 在上传之前，我用额外的边距调整了徽标，而不是在边缘裁剪。

最后结果：

Answer 5

您可以使用自定义 UINavigationItem，因此您只需要将 Main.storyboard 上的“Navigation Item”更改为 YourCustomClass。

在斯威夫特 3

class FixedImageNavigationItem: UINavigationItem {

private let fixedImage : UIImage = UIImage(named: "your-header-logo.png")!
private let imageView : UIImageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 50, height: 37.5))

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    imageView.contentMode = .scaleAspectFit
    imageView.image = fixedImage
    self.titleView = imageView

}

}

Answer 6

这在 2015 年 9 月对我有用 - 希望这可以帮助那里的人。

// 1
    var nav = self.navigationController?.navigationBar
    // 2 set the style 
    nav?.barStyle = UIBarStyle.Black
    nav?.tintColor = UIColor.yellowColor()
    // 3
    let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
    imageView.contentMode = .ScaleAspectFit
    // 4
    let image = UIImage(named: "logo.png")
    imageView.image = image
    // 5
    navigationItem.titleView = imageView

Answer 7

这是 Swift 4.2 的一个方便的函数，显示带有标题文本的图像：-

override func viewDidLoad() {

    super.viewDidLoad()

    //Sets the navigation title with text and image
    self.navigationItem.titleView = navTitleWithImageAndText(titleText: "Dean Stanley", imageName: "online")
}

func navTitleWithImageAndText(titleText: String, imageName: String) -> UIView {

    // Creates a new UIView
    let titleView = UIView()

    // Creates a new text label
    let label = UILabel()
    label.text = titleText
    label.sizeToFit()
    label.center = titleView.center
    label.textAlignment = NSTextAlignment.center

    // Creates the image view
    let image = UIImageView()
    image.image = UIImage(named: imageName)

    // Maintains the image's aspect ratio:
    let imageAspect = image.image!.size.width / image.image!.size.height

    // Sets the image frame so that it's immediately before the text:
    let imageX = label.frame.origin.x - label.frame.size.height * imageAspect
    let imageY = label.frame.origin.y

    let imageWidth = label.frame.size.height * imageAspect
    let imageHeight = label.frame.size.height

    image.frame = CGRect(x: imageX, y: imageY, width: imageWidth, height: imageHeight)

    image.contentMode = UIView.ContentMode.scaleAspectFit

    // Adds both the label and image view to the titleView
    titleView.addSubview(label)
    titleView.addSubview(image)

    // Sets the titleView frame to fit within the UINavigation Title
    titleView.sizeToFit()

    return titleView

}

Answer 8

斯威夫特 5.1，Xcode 11

有时，如果您的图像是高分辨率的，则 imageView 会从中心偏移，我建议使用此方法

  lazy var navigationTitleImageView = UIImageView()

  override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    self.setNavigationBar()
    
    self.navigationTitleImageView.image = logo
    self.navigationTitleImageView.contentMode = .scaleAspectFit
    
    self.navigationTitleImageView.translatesAutoresizingMaskIntoConstraints = false
    
    if let navC = self.navigationController{
        navC.navigationBar.addSubview(self.navigationTitleImageView)
        self.navigationTitleImageView.centerXAnchor.constraint(equalTo: navC.navigationBar.centerXAnchor).isActive = true
        self.navigationTitleImageView.centerYAnchor.constraint(equalTo: navC.navigationBar.centerYAnchor, constant: 0).isActive = true
        self.navigationTitleImageView.widthAnchor.constraint(equalTo: navC.navigationBar.widthAnchor, multiplier: 0.2).isActive = true
        self.navigationTitleImageView.heightAnchor.constraint(equalTo: navC.navigationBar.widthAnchor, multiplier: 0.088).isActive = true
    }
}

和 viewWillDisappear()

  override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    self.navigationTitleImageView.removeFromSuperview()
}

或者只是减小图像大小

Answer 9

我已经为 iOS 10 和 iOS 11 编写了这个，它对我有用：

extension UINavigationBar {
    func setupNavigationBar() {
        let titleImageWidth = frame.size.width * 0.32
        let titleImageHeight = frame.size.height * 0.64
        var navigationBarIconimageView = UIImageView()
        if #available(iOS 11.0, *) {
            navigationBarIconimageView.widthAnchor.constraint(equalToConstant: titleImageWidth).isActive = true
            navigationBarIconimageView.heightAnchor.constraint(equalToConstant: titleImageHeight).isActive = true
        } else {
            navigationBarIconimageView = UIImageView(frame: CGRect(x: 0, y: 0, width: titleImageWidth, height: titleImageHeight))
        }
        navigationBarIconimageView.contentMode = .scaleAspectFit
        navigationBarIconimageView.image = UIImage(named: "image")
        topItem?.titleView = navigationBarIconimageView
    }
}

Answer 10

如果您更喜欢使用自动布局，并希望在导航栏中有一个永久固定的图像，并且不会在每个屏幕上都显示动画，则此解决方案效果很好：

class CustomTitleNavigationController: UINavigationController {

override func viewDidLoad() {
    super.viewDidLoad()

    let logo = UIImage(named: "MyHeaderImage")

    let imageView = UIImageView(image:logo)
    imageView.contentMode = .scaleAspectFit
    imageView.translatesAutoresizingMaskIntoConstraints = false

    navigationBar.addSubview(imageView)

    navigationBar.addConstraint (navigationBar.leftAnchor.constraint(equalTo: imageView.leftAnchor, constant: 0))
    navigationBar.addConstraint (navigationBar.rightAnchor.constraint(equalTo: imageView.rightAnchor, constant: 0))
    navigationBar.addConstraint (navigationBar.topAnchor.constraint(equalTo: imageView.topAnchor, constant: 0))
    navigationBar.addConstraint (navigationBar.bottomAnchor.constraint(equalTo: imageView.bottomAnchor, constant: 0))
}

Answer 11

让我们试试结帐

let image = UIImage(named: "Navbar_bg.png")
navigationItem.titleView = UIImageView(image: image)
let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
imageView.contentMode = .ScaleAspectFit

Answer 12

适用于我的 swift 4（方形图像 40x40）

let imageView = UIImageView()
imageView.frame.size.width = 40
imageView.frame.size.height = 40
imageView.contentMode = .scaleAspectFit
let image = UIImage(named: "YOUR_IMAGE_NAME")
imageView.image = image
navigationItem.titleView = imageView

如果您想要其他措施，请尝试

let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 50, height: 100.5)))
imageView.contentMode = .scaleAspectFit
let image = UIImage(named: "YOUR_IMAGE_NAME")
imageView.image = image
navigationItem.titleView = imageView

我希望它为你服务。 这个对我有用。

Answer 13

    let imageView = UIImageView(frame: (CGRect(x: 0, y: 0, width: 40, height: 
    40)))
    imageView.contentMode = .scaleAspectFit
    let image = UIImage (named: "logo") // logo is your NPG asset 
    imageView.image = image
    self.navigationItem.titleView = imageView

Answer 14

可以像这样以编程方式完成。

private var imageView: UIView {

    let bannerWidth = navigationBar.frame.size.width * 0.5 // 0.5 its multiplier to get correct image width
    let bannerHeight = navigationBar.frame.size.height

    let view = UIView()
    view.backgroundColor = .clear
    view.frame = CGRect(x: 0, y: 0, width: bannerWidth, height: bannerHeight)

    let image = UIImage(named: "your_image_name")
    let imageView = UIImageView(image: image)
    imageView.contentMode = .scaleAspectFit
    imageView.frame = CGRect(x: 0, y: 0, width: view.frame.width, height: view.frame.height)

    view.addSubview(imageView)

    return view
}

只是改变titleView

navigationItem.titleView = imageView

Answer 15

这对我有用......试试吧

let image : UIImage = UIImage(named: "LogoName")
let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 25, height: 25))
imageView.contentMode = .scaleAspectFit
imageView.image = image
navigationItem.titleView = imageView

Answer 16

Objective-C版本：

//create the space for the image
UIImageView *myImage = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 256, 144)];
//bind the image with the ImageView allocated
myImage.image = [UIImage imageNamed:@"logo.png"];
//add image into imageview
_myNavigationItem.titleView = myImage;

以防万一有人（像我一样）来到这里寻找Objective-C的答案。

Answer 17

为了获得大小合适且居中的图像视图，您应该使用以下方法：

let width = 120 // choose the image width
let height = 20 // choose the image height
let titleView = UIView(frame: CGRect(x: 0, y: 0, width: view.bounds.width, height: 44)) //44 is the standard size of the top bar
let imageView = UIImageView(frame: CGRect(x: (view.bounds.width - width)/2, y: (44 - height)/2, width: width, height: height))
imageView.contentMode = .scaleAspectFit //choose other if it makes sense
imageView.image = UIImage(named: "your_image_name")
titleView.addSubview(imageView)
navigationItem.titleView = titleView