ios - 无法在 UIScrollView 中缩放 UIImageView
问题描述
我想放大UIImageView
,ScrollView
但我不知道怎么做。
import UIKit
class ViewController: UIViewController, UIScrollViewDelegate {
var scrollView: UIScrollView = UIScrollView()
var viewInScrollView: UIView = UIView()
var selectedImageView: UIImageView = UIImageView()
override func viewDidLoad() {
super.viewDidLoad()
scrollView.delegate = self
view.addSubview(scrollView)
scrollView.addSubview(viewInScrollView)
viewInScrollView.addSubview(selectedImageView)
selectedImageView.image = UIImage(named: "michael")
scrollView.translatesAutoresizingMaskIntoConstraints = false
viewInScrollView.translatesAutoresizingMaskIntoConstraints = false
selectedImageView.translatesAutoresizingMaskIntoConstraints = false
scrollView.anchor(top: view.safeAreaLayoutGuide.topAnchor, leading: view.leadingAnchor, bottom: view.bottomAnchor, trailing: view.trailingAnchor)
viewInScrollView.anchor(top: view.safeAreaLayoutGuide.topAnchor, leading: view.leadingAnchor, bottom: view.bottomAnchor, trailing: view.trailingAnchor)
viewInScrollView.widthAnchor.constraint(equalToConstant: view.frame.width).isActive = true
viewInScrollView.heightAnchor.constraint(equalToConstant: view.frame.height).isActive = true
selectedImageView.anchor(top: viewInScrollView.topAnchor, leading: viewInScrollView.leadingAnchor, bottom: viewInScrollView.bottomAnchor, trailing: viewInScrollView.trailingAnchor)
}
func viewForZooming(in scrollView: UIScrollView) -> UIView? {
return selectedImageView
}
}
解决方案
您必须将maximumZoomScale
,添加minimumZoomScale
到您scrollView
喜欢的以下内容中。
scrollView.minimumZoomScale = 0.25
scrollView.maximumZoomScale = 5.0
希望这有帮助!
推荐阅读
- travis-ci - Travis-Ci 不导入实用程序
- angular - 如何创建一个只有 typescript 模型类的 npm 库?
- kubernetes - Kubernetes中具有ClusterIP服务类型的外部IP地址有什么用
- docker - Docker 信任:无法将信任轮换到新的受信任根:无法使用当前受信任的证书验证数据
- java - BeanCreationException:由 ClassNotFoundException 引起的 NoClassDefFoundError 创建名称为“entityManagerFactory”的 bean 时出错
- reactjs - 是否有可能将状态/道具值从一个组件传递到另一个组件
- parsing - 如何使这个语法 LL(1)
- c# - 在 .NET Framework 和 .NET Core 之间自动传递和拉取 JSON 数据
- java - java.awt.AWTError: Can't connect to X11 window server using ':0' 作为 DISPLAY 变量的值
- google-analytics - Google Analytics(分析)中未显示 Ecom 跟踪