为什么我在使用 NSTimer 每隔 x 秒执行一次 运行 函数时会收到此错误消息？
Why am I getting this error message when I am using NSTimer to run function every x seconds?
我正在使用 NSTime 运行 按照建议每 x 秒执行一次函数 here。
我的问题是，每当 x 秒数到达并且该执行该功能时，我都会收到此错误消息。
2015-04-06 11:55:51.898 myapp[21611:1186926] -[myapp.ViewController getJson(sharedData.jsonUrl)]: unrecognized selector sent to instance 0x7fff48761d60
2015-04-06 11:55:51.902 myapp[21611:1186926] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[myapp.ViewController getJson(sharedData.jsonUrl)]: unrecognized selector sent to instance 0x7fff48761d60'
*** First throw call stack:
(
0 CoreFoundation 0x0000000101497a75 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000102fefbb7 objc_exception_throw + 45
2 CoreFoundation 0x000000010149ed1d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
3 CoreFoundation 0x00000001013f69dc ___forwarding___ + 988
4 CoreFoundation 0x00000001013f6578 _CF_forwarding_prep_0 + 120
5 Foundation 0x00000001018cf844 __NSFireTimer + 83
6 CoreFoundation 0x00000001013ff6c4 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
7 CoreFoundation 0x00000001013ff285 __CFRunLoopDoTimer + 1045
8 CoreFoundation 0x00000001013c259d __CFRunLoopRun + 1901
9 CoreFoundation 0x00000001013c1bc6 CFRunLoopRunSpecific + 470
10 GraphicsServices 0x00000001055a0a58 GSEventRunModal + 161
11 UIKit 0x0000000101d2a580 UIApplicationMain + 1282
12 maybe 0x0000000100ed55ee top_level_code + 78
13 myapp 0x0000000100ed562a main + 42
14 libdyld.dylib 0x00000001037cb145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
我知道该功能有效，因为我已经对其进行了单独测试。
我用来调用 NSTimer 函数的代码是：
override func viewDidLoad() {
super.viewDidLoad()
var timer = NSTimer.scheduledTimerWithTimeInterval(0.2, target: self, selector: "getJson(sharedData.jsonUrl)", userInfo: nil, repeats: true)
}
我不确定为什么会收到此错误。我已经尝试从调用和函数本身中删除参数，以便它与我从中学到的 SO 问题中的代码完全相同，但我没有运气。
我正在 swift 中写这篇文章。
这里有更多信息。 getJson 只是一个下载 JSON 文件并将一些值附加到数组的函数。 sharedData 是一个单例 class - 我用它来存储需要在不同视图控制器中使用的值。 jsonUrl 是 class 中的变量之一。所以 sharedData.jsonUrl 只是从 class 中获取变量。\
编辑：
这是我现在尝试使用的代码：
var 计时器 = NSTimer.scheduledTimerWithTimeInterval(
0.2,
目标：自己，
选择器："getJson:"，
用户信息：无，
重复：真）
确切的错误信息是：
2015-04-06 16:16:56.160 myapp[22712:1284267] -[myapp.settingsViewController getJson:]: unrecognized selector sent to instance 0x7f8c88c7d810
2015-04-06 16:16:56.165 myapp[22712:1284267] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[myapp.settingsViewController getJson:]: unrecognized selector sent to instance 0x7f8c88c7d810'
*** First throw call stack:
(
0 CoreFoundation 0x000000010a491a75 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x000000010bfe9bb7 objc_exception_throw + 45
2 CoreFoundation 0x000000010a498d1d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
3 CoreFoundation 0x000000010a3f09dc ___forwarding___ + 988
4 CoreFoundation 0x000000010a3f0578 _CF_forwarding_prep_0 + 120
5 Foundation 0x000000010a8c9844 __NSFireTimer + 83
6 CoreFoundation 0x000000010a3f96c4 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
7 CoreFoundation 0x000000010a3f9285 __CFRunLoopDoTimer + 1045
8 CoreFoundation 0x000000010a3bc59d __CFRunLoopRun + 1901
9 CoreFoundation 0x000000010a3bbbc6 CFRunLoopRunSpecific + 470
10 GraphicsServices 0x000000010e59aa58 GSEventRunModal + 161
11 UIKit 0x000000010ad24580 UIApplicationMain + 1282
12 myapp 0x0000000109ed41ce top_level_code + 78
13 myapp 0x0000000109ed420a main + 42
14 libdyld.dylib 0x000000010c7c5145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
获取getJson函数是：
func getJson() {
let urlPath = sharedData.jsonUrl.absoluteString
let url: NSURL = NSURL(string: urlPath!)!
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(url, completionHandler: {data, response, error -> Void in
if error != nil {
// If there is an error in the web request, print it to the console
println(error.localizedDescription)
}
var err: NSError?
var jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as NSDictionary
if err != nil {
// If there is an error parsing JSON, print it to the console
println("JSON Error \(err!.localizedDescription)")
}
let json = JSON(jsonResult)
var teamCount = json["teamCount"].string! // Number in array
var teamCountInt: Int = teamCount.toInt()! // Converts to integer
for index in 0...teamCountInt - 1 { // loop for number in array
let teamJson = json["teams"][index]["\(index)"].string! //
sharedData.teamsArray.append(teamJson) // Appends to array in shared data
}
println(sharedData.teamsArray) // For debug - delete after
})
task.resume()
}
此函数使用Swifty-json.
你的post是乱码。计时器调用中包含格式错误的降价 link，因此很难判断我们在看什么。
不过，查看错误消息表明您的选择器是 getJsonTeams(sharedData.jsonUrl)，这是无效的。您将选择放在 Objective-C 语法中，没有括号也没有参数。您的选择器可能应该是 getJsonTeams:
编辑：
您的代码应为
var timer = NSTimer.scheduledTimerWithTimeInterval(
0.2,
target: self,
selector: "getJson:",
userInfo: nil,
repeats: true)
选择器应采用 Objective-C 语法，并且绝不应包含括号或参数。如果该方法采用单个参数，则选择器名称应以冒号结尾。
修改getJson()方法如下：
class SomeGoodClassName {
func getJson(timer: NSTimer) {
//Directly use shareData.jsonUrl here to get json data
//... more code
}
}
NSTimer初始化
let jsonLoader = SomeGoodClassName()
override func viewDidLoad() {
super.viewDidLoad()
var timer = NSTimer.scheduledTimerWithTimeInterval(0.2, target: jsonLoader, selector: "getJson", userInfo: nil, repeats: true)
}
我正在使用 NSTime 运行 按照建议每 x 秒执行一次函数 here。
我的问题是，每当 x 秒数到达并且该执行该功能时，我都会收到此错误消息。
2015-04-06 11:55:51.898 myapp[21611:1186926] -[myapp.ViewController getJson(sharedData.jsonUrl)]: unrecognized selector sent to instance 0x7fff48761d60
2015-04-06 11:55:51.902 myapp[21611:1186926] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[myapp.ViewController getJson(sharedData.jsonUrl)]: unrecognized selector sent to instance 0x7fff48761d60'
*** First throw call stack:
(
0 CoreFoundation 0x0000000101497a75 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000102fefbb7 objc_exception_throw + 45
2 CoreFoundation 0x000000010149ed1d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
3 CoreFoundation 0x00000001013f69dc ___forwarding___ + 988
4 CoreFoundation 0x00000001013f6578 _CF_forwarding_prep_0 + 120
5 Foundation 0x00000001018cf844 __NSFireTimer + 83
6 CoreFoundation 0x00000001013ff6c4 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
7 CoreFoundation 0x00000001013ff285 __CFRunLoopDoTimer + 1045
8 CoreFoundation 0x00000001013c259d __CFRunLoopRun + 1901
9 CoreFoundation 0x00000001013c1bc6 CFRunLoopRunSpecific + 470
10 GraphicsServices 0x00000001055a0a58 GSEventRunModal + 161
11 UIKit 0x0000000101d2a580 UIApplicationMain + 1282
12 maybe 0x0000000100ed55ee top_level_code + 78
13 myapp 0x0000000100ed562a main + 42
14 libdyld.dylib 0x00000001037cb145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
我知道该功能有效，因为我已经对其进行了单独测试。
我用来调用 NSTimer 函数的代码是：
override func viewDidLoad() {
super.viewDidLoad()
var timer = NSTimer.scheduledTimerWithTimeInterval(0.2, target: self, selector: "getJson(sharedData.jsonUrl)", userInfo: nil, repeats: true)
}
我不确定为什么会收到此错误。我已经尝试从调用和函数本身中删除参数，以便它与我从中学到的 SO 问题中的代码完全相同，但我没有运气。
我正在 swift 中写这篇文章。
这里有更多信息。 getJson 只是一个下载 JSON 文件并将一些值附加到数组的函数。 sharedData 是一个单例 class - 我用它来存储需要在不同视图控制器中使用的值。 jsonUrl 是 class 中的变量之一。所以 sharedData.jsonUrl 只是从 class 中获取变量。\
编辑：
这是我现在尝试使用的代码： var 计时器 = NSTimer.scheduledTimerWithTimeInterval( 0.2, 目标：自己， 选择器："getJson:"， 用户信息：无， 重复：真）
确切的错误信息是：
2015-04-06 16:16:56.160 myapp[22712:1284267] -[myapp.settingsViewController getJson:]: unrecognized selector sent to instance 0x7f8c88c7d810
2015-04-06 16:16:56.165 myapp[22712:1284267] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[myapp.settingsViewController getJson:]: unrecognized selector sent to instance 0x7f8c88c7d810'
*** First throw call stack:
(
0 CoreFoundation 0x000000010a491a75 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x000000010bfe9bb7 objc_exception_throw + 45
2 CoreFoundation 0x000000010a498d1d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
3 CoreFoundation 0x000000010a3f09dc ___forwarding___ + 988
4 CoreFoundation 0x000000010a3f0578 _CF_forwarding_prep_0 + 120
5 Foundation 0x000000010a8c9844 __NSFireTimer + 83
6 CoreFoundation 0x000000010a3f96c4 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
7 CoreFoundation 0x000000010a3f9285 __CFRunLoopDoTimer + 1045
8 CoreFoundation 0x000000010a3bc59d __CFRunLoopRun + 1901
9 CoreFoundation 0x000000010a3bbbc6 CFRunLoopRunSpecific + 470
10 GraphicsServices 0x000000010e59aa58 GSEventRunModal + 161
11 UIKit 0x000000010ad24580 UIApplicationMain + 1282
12 myapp 0x0000000109ed41ce top_level_code + 78
13 myapp 0x0000000109ed420a main + 42
14 libdyld.dylib 0x000000010c7c5145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
获取getJson函数是：
func getJson() {
let urlPath = sharedData.jsonUrl.absoluteString
let url: NSURL = NSURL(string: urlPath!)!
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(url, completionHandler: {data, response, error -> Void in
if error != nil {
// If there is an error in the web request, print it to the console
println(error.localizedDescription)
}
var err: NSError?
var jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as NSDictionary
if err != nil {
// If there is an error parsing JSON, print it to the console
println("JSON Error \(err!.localizedDescription)")
}
let json = JSON(jsonResult)
var teamCount = json["teamCount"].string! // Number in array
var teamCountInt: Int = teamCount.toInt()! // Converts to integer
for index in 0...teamCountInt - 1 { // loop for number in array
let teamJson = json["teams"][index]["\(index)"].string! //
sharedData.teamsArray.append(teamJson) // Appends to array in shared data
}
println(sharedData.teamsArray) // For debug - delete after
})
task.resume()
}
此函数使用Swifty-json.
你的post是乱码。计时器调用中包含格式错误的降价 link，因此很难判断我们在看什么。
不过，查看错误消息表明您的选择器是 getJsonTeams(sharedData.jsonUrl)，这是无效的。您将选择放在 Objective-C 语法中，没有括号也没有参数。您的选择器可能应该是 getJsonTeams:
编辑：
您的代码应为
var timer = NSTimer.scheduledTimerWithTimeInterval(
0.2,
target: self,
selector: "getJson:",
userInfo: nil,
repeats: true)
选择器应采用 Objective-C 语法，并且绝不应包含括号或参数。如果该方法采用单个参数，则选择器名称应以冒号结尾。
修改getJson()方法如下：
class SomeGoodClassName {
func getJson(timer: NSTimer) {
//Directly use shareData.jsonUrl here to get json data
//... more code
}
}
NSTimer初始化
let jsonLoader = SomeGoodClassName()
override func viewDidLoad() {
super.viewDidLoad()
var timer = NSTimer.scheduledTimerWithTimeInterval(0.2, target: jsonLoader, selector: "getJson", userInfo: nil, repeats: true)
}