navigationController 在执行 segue 时为零?
navigationController is nil while performing segue?
我正在使用一个名为 SwiftPages 的库。它工作正常。但是当我从这个 View Controller 执行 Push Segue 到另一个时,导航栏 self.navigationController 是 nil ?
如何将导航栏添加到推送的 VC 中?
ViewController
class CoursePageController: UIViewController, UITableViewDataSource, UITableViewDelegate {
@IBOutlet weak var ChapterTable: UITableView!
@IBOutlet weak var courseDesc: UITextView!
var CourseName : String!
var ChapName : [String] = []
var ChapId : [String] = []
override func viewDidLoad() {
super.viewDidLoad()
self.title = CourseName
self.courseDesc.text = CourseDescriptionC
self.courseDesc.setContentOffset(CGPointZero, animated: true)
HUD()
ChapterTable.estimatedRowHeight = 120
ChapterTable.rowHeight = UITableViewAutomaticDimension
getData()
}
func HUD(){
progress.show(style: MyStyle())
}
func getData(){
Alamofire.request(.GET, "http://www.wve.com/index.php/capp/get_chapter_by_course_id/\(CourseIdinController)")
.responseJSON { (_, _, data, _) in
let json = JSON(data!)
let catCount = json.count
for index in 0...catCount-1 {
let cname = json[index]["CHAPTER_NAME"].string
let cid = json[index]["CHAPTER_ID"].string
self.ChapName.append(cname!)
self.ChapId.append(cid!)
}
self.ChapterTable.reloadData()
self.progress.dismiss()
}
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Potentially incomplete method implementation.
// Return the number of sections.
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete method implementation.
// Return the number of rows in the section.
return ChapName.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell : UITableViewCell = self.ChapterTable.dequeueReusableCellWithIdentifier("ChapCell") as! UITableViewCell
cell.textLabel?.text = self.ChapName[indexPath.row]
return cell
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
//Here the navigationController is nil
self.navigationController?.pushViewController(self.storyboard!.instantiateViewControllerWithIdentifier("LessonController") as! UIViewController, animated: true)
// performSegueWithIdentifier("ChapSegue", sender: nil)
}
编辑
我已将导航控制器添加为初始 VC。课程页面控制器显示在 SwiftPages 中。
我找不到它是如何呈现的。请看一下这个文件。
https://github.com/GabrielAlva/SwiftPages/blob/master/SwiftPages/SwiftPages.swift
提前致谢!
你把CoursePageController放在NavigationController里了吗?如果是,那么检查它是如何呈现的?
如果它以模态方式呈现,那么您将不会获得 navigationController 引用。
如果您将 navController 作为 rootViewController,这将起作用
if let navController = UIApplication.sharedApplication().keyWindow?.rootViewController as? UINavigationController {
//get the nav controller here and try to push your anotherViewController
}
我正在使用一个名为 SwiftPages 的库。它工作正常。但是当我从这个 View Controller 执行 Push Segue 到另一个时,导航栏 self.navigationController 是 nil ?
如何将导航栏添加到推送的 VC 中?
ViewController
class CoursePageController: UIViewController, UITableViewDataSource, UITableViewDelegate {
@IBOutlet weak var ChapterTable: UITableView!
@IBOutlet weak var courseDesc: UITextView!
var CourseName : String!
var ChapName : [String] = []
var ChapId : [String] = []
override func viewDidLoad() {
super.viewDidLoad()
self.title = CourseName
self.courseDesc.text = CourseDescriptionC
self.courseDesc.setContentOffset(CGPointZero, animated: true)
HUD()
ChapterTable.estimatedRowHeight = 120
ChapterTable.rowHeight = UITableViewAutomaticDimension
getData()
}
func HUD(){
progress.show(style: MyStyle())
}
func getData(){
Alamofire.request(.GET, "http://www.wve.com/index.php/capp/get_chapter_by_course_id/\(CourseIdinController)")
.responseJSON { (_, _, data, _) in
let json = JSON(data!)
let catCount = json.count
for index in 0...catCount-1 {
let cname = json[index]["CHAPTER_NAME"].string
let cid = json[index]["CHAPTER_ID"].string
self.ChapName.append(cname!)
self.ChapId.append(cid!)
}
self.ChapterTable.reloadData()
self.progress.dismiss()
}
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Potentially incomplete method implementation.
// Return the number of sections.
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete method implementation.
// Return the number of rows in the section.
return ChapName.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell : UITableViewCell = self.ChapterTable.dequeueReusableCellWithIdentifier("ChapCell") as! UITableViewCell
cell.textLabel?.text = self.ChapName[indexPath.row]
return cell
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
//Here the navigationController is nil
self.navigationController?.pushViewController(self.storyboard!.instantiateViewControllerWithIdentifier("LessonController") as! UIViewController, animated: true)
// performSegueWithIdentifier("ChapSegue", sender: nil)
}
编辑
我已将导航控制器添加为初始 VC。课程页面控制器显示在 SwiftPages 中。
我找不到它是如何呈现的。请看一下这个文件。 https://github.com/GabrielAlva/SwiftPages/blob/master/SwiftPages/SwiftPages.swift
提前致谢!
你把CoursePageController放在NavigationController里了吗?如果是,那么检查它是如何呈现的?
如果它以模态方式呈现,那么您将不会获得 navigationController 引用。
如果您将 navController 作为 rootViewController,这将起作用
if let navController = UIApplication.sharedApplication().keyWindow?.rootViewController as? UINavigationController {
//get the nav controller here and try to push your anotherViewController
}