问题
I have added a search bar and search display controller from the interface builder to my app. I am not able to get it to deinit (dealloc) properly.
It is showing the following behavior (swift2, ios9):
- User doesn't search anything, just selects an item from tableView, DEINIT is called
- User searches something (or just taps in the search bar), cancel the search, select item from tableView, DEINIT is called
- User searches something (or just taps the search bar), and selects an item from tableView, DEINIT is NOT called :(
The same behaviour occurs if I select "Back" in the navigation controller instead of selecting an item.
code removed - refer to COMPLETE CODE at bottom of post.
Any help appreciated!
UPDATE Further testing has shown that removing the progressHud/loadingHud from the view controller entirely has no impact on the DEINIT not getting called. It must be something to do with the tableview or the searchcontroller itself...
UPDATE 2 I have tried calling the searchBarCancelButtonClicked() method in my viewWillDissapear and it still doesn't release. Even though if you click "cancel" and then navigate away it does...
UPDATE 3 Changing the willDisappear/didDisappear to the following has had no impact on the DEINIT - but does not give buggy interface issues (thanks Polina). I am trying to nil out anything I can to get a release, but no luck so far.
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(true)
searchBarCancelButtonClicked(searchController.searchBar)
}
override func viewDidDisappear(animated: Bool) {
print("View did disappear")
searchController.searchBar.resignFirstResponder()
searchController.searchBar.endEditing(true)
searchController.active = false
loadingHud.removeFromSuperview()
progressHud.removeFromSuperview()
searchController.searchBar.delegate = nil
searchController.searchResultsUpdater = nil
searchController = nil
tableView = nil
super.viewDidDisappear(true)
}
UPDATE 4 Still no answer I've found. Really hoping someone can help!
UPDATE 5 In response to @ConfusedByCode - I have updated the following methods to use [unowned self] in inside of all closure or background thread operations:
code removed - refer to COMPLETE CODE at bottom of post
I am still not seeing DEINIT. I'm checking to make sure I didn't make a silly mistake somewhere.
UPDATE 6 I have removed extra weak self's and made sure the closures are utilizing [weak self] in and unwrapping them safely. The DEINIT still is not called.
UPDATE 7 Changed two things to no avail - made appDel unowned let appDel, and put searchBar.resignFirstResponder() in finishSearch(). Still not receiving deinit.
COMPLETE CODE: (REPRESENTS UPDATE 7)
FOR CORRECT ANSWER SEE CODE PASTED UNDER CORRECTED CODE
class AirportSearchTBVC: UITableViewController, UISearchResultsUpdating, UISearchBarDelegate {
var airportData = [Dictionary<String, String>]()
var filteredData = [Dictionary<String, String>]()
var searchController: UISearchController!
unowned let appDel = UIApplication.sharedApplication().delegate as! AppDelegate
var progressHud: ProgressHUD!
var loadingHud: ProgressHUD!
var arrDepOfFlight: String!
var dateOfFlight: NSDate!
var tailNum: String!
var selectedAirportIdent: String!
deinit {
print("TBVC Dealloc")
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(true)
progressHud = ProgressHUD(text: "Searching")
loadingHud = ProgressHUD(text: "Loading")
searchController = UISearchController(searchResultsController: nil)
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
searchController.searchBar.sizeToFit()
tableView.tableHeaderView = searchController.searchBar
definesPresentationContext = true
searchController.hidesNavigationBarDuringPresentation = false
searchController.searchBar.delegate = self
view.addSubview(loadingHud)
appDel.backgroundThread(background: { [weak self] in
if let weakSelf = self {
let airportHelper = AirportHelper()
weakSelf.airportData = airportHelper.getAirportSearchData()
}
},
completion: {
dispatch_async(dispatch_get_main_queue()) { [weak self] in
if let weakSelf = self {
if weakSelf.isVisible && weakSelf.isTopViewController {
weakSelf.filteredData = (weakSelf.airportData)
weakSelf.loadingHud.removeFromSuperview()
weakSelf.updateSearchResultsForSearchController(weakSelf.searchController)
weakSelf.tableView.reloadData()
}
}
}
});
}
//MARK: Searchbar methods (All background thread methods are in here)
func searchBarCancelButtonClicked(searchBar: UISearchBar) {
searchController.searchBar.endEditing(true)
searchController.searchBar.resignFirstResponder()
filteredData = airportData
tableView.reloadData()
}
func searchBarSearchButtonClicked(searchBar: UISearchBar) {
if isVisible && isTopViewController {
if let startCount = searchController.searchBar.text?.length {
if searchController.searchBar.text!.length >= 3 && searchController.searchBar.text!.length == startCount{
view.addSubview(progressHud)
finishSearch()
}
}
}
}
func finishSearch () {
appDel.backgroundThread(background: { [weak self] in
if let weakSelf = self {
if weakSelf.isVisible && weakSelf.isTopViewController {
let searchText = weakSelf.searchController.searchBar.text!.lowercaseString
weakSelf.searchController.searchBar.resignFirstResponder()
weakSelf.filteredData = weakSelf.airportData.filter{
if let ident = $0["ident"] {
if ident.lowercaseString.rangeOfString(searchText) != nil {
return true
}
}
if let name = $0["name"] {
if name.lowercaseString.rangeOfString(searchText) != nil {
return true
}
}
if let city = $0["municipality"] {
if city.lowercaseString.rangeOfString(searchText) != nil {
return true
}
}
return false
}
}
}
},
completion: {
dispatch_async(dispatch_get_main_queue()) { [weak self] in
if let weakSelf = self {
if weakSelf.isVisible && weakSelf.isTopViewController {
weakSelf.tableView.reloadData()
weakSelf.progressHud.removeFromSuperview()
}
}
}
});
}
func updateSearchResultsForSearchController(searchController: UISearchController) {
if isVisible && isTopViewController {
if let startCount = searchController.searchBar.text?.length {
if searchController.searchBar.text!.length >= 3 && searchController.searchBar.text!.length == startCount{
view.addSubview(progressHud)
finishSearch()
}
}
}
}
//MARK: Table view methods:
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return 72
}
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
if searchController.active {
return filteredData.count
} else {
return airportData.count
}
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell: AirportSearchTableViewCell
cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! AirportSearchTableViewCell
if searchController.active {
let airportDict = filteredData[indexPath.row]
let airportIdent = airportDict["ident"]
let airportName = airportDict["name"]
let airportRegion = airportDict["iso_region"]
let airportCity = airportDict["municipality"]
cell.loadItem(airportIdent, name: airportName, region: airportRegion, city: airportCity)
} else {
let airportDict = airportData[indexPath.row]
let airportIdent = airportDict["ident"]
let airportName = airportDict["name"]
let airportRegion = airportDict["iso_region"]
let airportCity = airportDict["municipality"]
cell.loadItem(airportIdent, name: airportName, region: airportRegion, city: airportCity)
}
return cell
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(true)
searchBarCancelButtonClicked(searchController.searchBar)
}
override func viewDidDisappear(animated: Bool) {
print("View did disappear")
searchController.searchBar.resignFirstResponder()
searchController.searchBar.endEditing(true)
searchController.active = false
searchController.delegate = nil
searchController.resignFirstResponder()
loadingHud.removeFromSuperview()
progressHud.removeFromSuperview()
searchController.searchBar.delegate = nil
searchController.searchResultsUpdater = nil
searchController.removeFromParentViewController()
searchController = nil
tableView = nil
super.viewDidDisappear(true)
}
func delay(delay:Double, closure:()->()) {
dispatch_after(
dispatch_time(
DISPATCH_TIME_NOW,
Int64(delay * Double(NSEC_PER_SEC))
),
dispatch_get_main_queue(), closure)
}
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
let cell = tableView.cellForRowAtIndexPath(indexPath) as! AirportSearchTableViewCell
selectedAirportIdent = cell.identLbl.text!
self.performSegueWithIdentifier("searchMapVC", sender: nil)
tableView.deselectRowAtIndexPath(indexPath, animated: true)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
if segue.identifier == "searchMapVC" {
let mapVC = segue.destinationViewController as! SearchMapController
mapVC.arrDepOfFlight = arrDepOfFlight
mapVC.dateOfFlight = dateOfFlight
mapVC.tailNum = tailNum
mapVC.selectedAirportIdent = selectedAirportIdent
}
}
}
//MARK: EXTENSIONS
extension String {
var length: Int { return characters.count } // Swift 2.0
}
extension UIViewController {
public var isVisible: Bool {
if isViewLoaded() {
return view.window != nil
}
return false
}
public var isTopViewController: Bool {
if self.navigationController != nil {
return self.navigationController?.visibleViewController === self
} else if self.tabBarController != nil {
return self.tabBarController?.selectedViewController == self && self.presentedViewController == nil
} else {
return self.presentedViewController == nil && self.isVisible
}
}
}
CORRECTED CODE [FIXED] As Mikael Hellman suggested, there is some sort of retain bug occurring with definesPresentationContext which was originally in my viewWillAppear method. I have removed that line and done some slight massaging of my code. It is now working perfectly.
Thank you so much for the effort and the answer! Also, thank you to @confusedByCode for the help - I am sure his suggestions were a component of my problem as well, but didn't end up being the final answer.
import UIKit
class AirportSearchTBVC: UITableViewController, UISearchResultsUpdating, UISearchBarDelegate {
var airportData = [Dictionary<String, String>]()
var filteredData = [Dictionary<String, String>]()
var searchController: UISearchController!
let appDel = UIApplication.sharedApplication().delegate as! AppDelegate
var progressHud: ProgressHUD!
var loadingHud: ProgressHUD!
var arrDepOfFlight: String!
var dateOfFlight: NSDate!
var tailNum: String!
var selectedAirportIdent: String!
deinit {
print("TBVC Dealloc")
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(true)
progressHud = ProgressHUD(text: "Searching")
loadingHud = ProgressHUD(text: "Loading")
searchController = UISearchController(searchResultsController: nil)
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
searchController.searchBar.sizeToFit()
tableView.tableHeaderView = searchController.searchBar
//definesPresentationContext = true
searchController.hidesNavigationBarDuringPresentation = false
searchController.searchBar.delegate = self
view.addSubview(loadingHud)
appDel.backgroundThread(background: { [weak self] in
if let weakSelf = self {
let airportHelper = AirportHelper()
weakSelf.airportData = airportHelper.getAirportSearchData()
}
},
completion: {
dispatch_async(dispatch_get_main_queue()) { [weak self] in
if let weakSelf = self {
print("isVisible: \(weakSelf.isVisible)")
print("isTopViewController: \(weakSelf.isTopViewController)")
if weakSelf.isVisible {
weakSelf.filteredData = (weakSelf.airportData)
weakSelf.loadingHud.removeFromSuperview()
weakSelf.updateSearchResultsForSearchController(weakSelf.searchController)
weakSelf.tableView.reloadData()
}
}
}
});
}
//MARK: Searchbar methods (All background thread methods are in here)
func searchBarCancelButtonClicked(searchBar: UISearchBar) {
searchController.searchBar.endEditing(true)
searchController.searchBar.resignFirstResponder()
filteredData = airportData
tableView.reloadData()
}
func searchBarSearchButtonClicked(searchBar: UISearchBar) {
if let startCount = searchController.searchBar.text?.length {
if searchController.searchBar.text!.length >= 3 && searchController.searchBar.text!.length == startCount{
view.addSubview(progressHud)
finishSearch()
}
}
}
func finishSearch () {
appDel.backgroundThread(background: { [weak self] in
if let weakSelf = self {
let searchText = weakSelf.searchController.searchBar.text!.lowercaseString
//weakSelf.searchController.searchBar.resignFirstResponder()
weakSelf.filteredData = weakSelf.airportData.filter{
if let ident = $0["ident"] {
if ident.lowercaseString.rangeOfString(searchText) != nil {
return true
}
}
if let name = $0["name"] {
if name.lowercaseString.rangeOfString(searchText) != nil {
return true
}
}
if let city = $0["municipality"] {
if city.lowercaseString.rangeOfString(searchText) != nil {
return true
}
}
return false
}
}
},
completion: {
dispatch_async(dispatch_get_main_queue()) { [unowned self] in
if self.isVisible {
self.tableView.reloadData()
self.progressHud.removeFromSuperview()
}
}
});
}
func updateSearchResultsForSearchController(searchController: UISearchController) {
if let startCount = searchController.searchBar.text?.length {
if searchController.searchBar.text!.length >= 3 && searchController.searchBar.text!.length == startCount{
view.addSubview(progressHud)
finishSearch()
}
}
}
//MARK: Table view methods:
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return 72
}
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
if searchController.active {
return filteredData.count
} else {
return airportData.count
}
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell: AirportSearchTableViewCell
cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! AirportSearchTableViewCell
if searchController.active {
let airportDict = filteredData[indexPath.row]
let airportIdent = airportDict["ident"]
let airportName = airportDict["name"]
let airportRegion = airportDict["iso_region"]
let airportCity = airportDict["municipality"]
cell.loadItem(airportIdent, name: airportName, region: airportRegion, city: airportCity)
} else {
let airportDict = airportData[indexPath.row]
let airportIdent = airportDict["ident"]
let airportName = airportDict["name"]
let airportRegion = airportDict["iso_region"]
let airportCity = airportDict["municipality"]
cell.loadItem(airportIdent, name: airportName, region: airportRegion, city: airportCity)
}
return cell
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(true)
searchController.active = false
loadingHud.removeFromSuperview()
progressHud.removeFromSuperview()
}
override func viewDidDisappear(animated: Bool) {
print("View did disappear")
super.viewDidDisappear(true)
}
func delay(delay:Double, closure:()->()) {
dispatch_after(
dispatch_time(
DISPATCH_TIME_NOW,
Int64(delay * Double(NSEC_PER_SEC))
),
dispatch_get_main_queue(), closure)
}
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
let cell = tableView.cellForRowAtIndexPath(indexPath) as! AirportSearchTableViewCell
selectedAirportIdent = cell.identLbl.text!
self.performSegueWithIdentifier("searchMapVC", sender: nil)
tableView.deselectRowAtIndexPath(indexPath, animated: true)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
if segue.identifier == "searchMapVC" {
let mapVC = segue.destinationViewController as! SearchMapController
mapVC.arrDepOfFlight = arrDepOfFlight
mapVC.dateOfFlight = dateOfFlight
mapVC.tailNum = tailNum
mapVC.selectedAirportIdent = selectedAirportIdent
}
}
}
//MARK: EXTENSIONS
extension String {
var length: Int { return characters.count } // Swift 2.0
}
extension UIViewController {
public var isVisible: Bool {
if isViewLoaded() {
return view.window != nil
}
return false
}
public var isTopViewController: Bool {
if self.navigationController != nil {
return self.navigationController?.visibleViewController === self
} else if self.tabBarController != nil {
return self.tabBarController?.selectedViewController == self && self.presentedViewController == nil
} else {
return self.presentedViewController == nil && self.isVisible
}
}
}
回答1:
Deleted my old answer, found the problem.
Remove:
definesPresentationContext = true // Remove this line...
Read about it here:
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIViewController_Class/#//apple_ref/occ/instp/UIViewController/definesPresentationContext
There must a bug in UISearchController. Some Apple code must be retaining your controller.
Maybe the transition view (animation) is not completed when the controller is unlinked (it has special toView and fromView etc, that we can not reach), and this prevents the controller from being deallocated.
I think you should file this as a bug with Apple.
Also I would recommend changing your deinit to:
deinit {
print("TBVC Dealloc")
if let superView = searchController.view.superview
{
superView.removeFromSuperview()
}
}
This will ensure the search controller is never trying to present stuff when getting deallocated, as this creates warnings and potential unexpected behavior.
回答2:
I ran into this issue today as well this line of code seems to work to get your class released
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
searchController?.dismissViewControllerAnimated(false, completion: nil)
}
Here is my sample project on dropbox https://www.dropbox.com/s/zzs0m4n9maxd2u5/TestSearch.zip?dl=0
回答3:
I think the problem is that you are creating strong reference cycles between your closures and self, because you are using an unwrapped weak self in the closures.
For example, this:
if let safeSelf = weakSelf {
appDel.backgroundThread(background: {
let airportHelper = AirportHelper()
safeSelf.airportData = airportHelper.getAirportSearchData()
},
completion: {
dispatch_async(dispatch_get_main_queue()) {
if safeSelf.isVisible && safeSelf.isTopViewController {
safeSelf.filteredData = (safeSelf.airportData)
safeSelf.loadingHud.removeFromSuperview()
safeSelf.tableView.reloadData()
}
}
});
}
Should be:
appDel.backgroundThread(background: { [weak self] in
let airportHelper = AirportHelper()
self?.airportData = airportHelper.getAirportSearchData()
},
completion: {
dispatch_async(dispatch_get_main_queue()) { [weak self] in
if self?.isVisible && safeSelf.isTopViewController {
self?.filteredData = (safeSelf.airportData)
self?.loadingHud.removeFromSuperview()
self?.tableView.reloadData()
}
}
});
You can also use [unowned self] and you won't have to treat them as optional, but to be honest, I forget the pros and cons of unowned vs. weak. But I'm confident that if you declare the weak self or unowned self in a capture list in the closure, rather than outside of the closure and unwrapping it, your object will be properly deinitialized.
来源：https://stackoverflow.com/questions/33487603/tableview-with-searchcontroller-deinit-not-called