我正在Swift 4中编写一个应用程序,它应该适用于iOS 10.4和iOS 9.3。但是,我不知道如何为两个iOS版本实现初始化程序。
我收到错误消息:CoreData:错误:无法在NSManagedObject类'DeltaSigmaTestsignalGenerator.Project'上调用指定的初始化程序
以下空子类由Create NSManagedObject子类生成器自动创建:
import Foundation
import CoreData
public class Project: NSManagedObject {
}
以下函数应生成新的项目对象
func addNewProject(projectName: String, version: String) {
var newProject: Project!
if #available(iOS 10.0, *) {
newProject = Project(context: managedContext!)
}
else {
newProject = Project()
}
newProject.projectName = projectName
let newVersion = createNewVersion(versionName: version)
newProject.addToVersions(newVersion)
projekte.append(newProject)
do {
try managedContext!.save()
}
catch let error as NSError {
print("Save error: \(error), \(error.userInfo)")
}
}// End of addNewProject
在else
分支写
newProject = NSEntityDescription.insertNewObject(forEntityName: "Project", into: managedContext!) as! Project
并将newProject
声明为常量且非可选(不,您不会收到编译器错误)
let newProject: Project