如何在iPhone上检测首次启动应用程序

Question

我怎样才能检测到第一次发布

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
  // if very first launch than perform actionA
  // else perform actionB
}

方法？

Answer 1

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    if (![[NSUserDefaults standardUserDefaults] boolForKey:@"HasLaunchedOnce"])
    {
        [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"HasLaunchedOnce"];
        [[NSUserDefaults standardUserDefaults] synchronize];
    }
    return YES;
}

Answer 2

对于Xcode 7中的Swift 2.0。在AppDelegate.swift文件中：

import UIKit

@UIApplicationMain

class AppDelegate: UIResponder, UIApplicationDelegate {

var window: UIWindow?

func application(application: UIApplication, willFinishLaunchingWithOptions launchOptions: [NSObject : AnyObject]?) -> Bool
{
    return true
}


func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool
{
    didFinishLaunchingOnce()
    return true
}

func didFinishLaunchingOnce() -> Bool
{
    let defaults = NSUserDefaults.standardUserDefaults()

    if let hasBeenLauncherBefore = defaults.stringForKey("hasAppBeenLaunchedBefore")
    {
        //print(" N-th time app launched ")
        return true
    }
    else
    {
        //print(" First time app launched ")
        defaults.setBool(true, forKey: "hasAppBeenLaunchedBefore")
        return false
    }
}

}

Answer 3

快速简便的功能

- (BOOL) isFirstTimeOpening {
    NSUserDefaults *theDefaults = [NSUserDefaults standardUserDefaults];
    if([theDefaults integerForKey:@"hasRun"] == 0) {
        [theDefaults setInteger:1 forKey:@"hasRun"];
        [theDefaults synchronize];
        return true;
    }
    return false;
}

Answer 4

NSUserDefaults + Macro

最好的方法是使用NSUserDefaults并保存BOOL变量。如上所述，以下代码可以正常运行：

NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
[userDefaults setObject:[NSNumber numberWithBool:true] forKey:@"~applicationHasLaunchedBefore"];
[userDefaults synchronize];

您还可以创建如下的宏，以便轻松检查它是否是第一次启动

#define kApplicationHasLaunchedBefore [[NSUserDefaults standardUserDefaults] objectForKey:@"~applicationHasLaunchedBefore"]

然后使用它，

if (kApplicationHasLaunchedBefore) {
    //App has previously launched
} else {
    //App has not previously launched
}

Answer 5

这是一个在swift 5.0中工作的答案。与@Zaid Pathan的答案相比，改进是没有隐藏的合同。如果在调用setFirstAppLaunch()之前没有调用isFirstAppLaunch()，则会出现断言错误（仅在调试模式下）。

fileprivate struct _firstAppLaunchStaticData {
    static var alreadyCalled = false
    static var isFirstAppLaunch = true
    static let appAlreadyLaunchedString = "__private__appAlreadyLaunchedOnce"
}

func setFirstAppLaunch() {
    assert(_firstAppLaunchStaticData.alreadyCalled == false, "[Error] You called setFirstAppLaunch more than once")
    _firstAppLaunchStaticData.alreadyCalled = true
    let defaults = UserDefaults.standard

    if defaults.string(forKey: _firstAppLaunchStaticData.appAlreadyLaunchedString) != nil {
        _firstAppLaunchStaticData.isFirstAppLaunch = false
    }
    defaults.set(true, forKey: _firstAppLaunchStaticData.appAlreadyLaunchedString)
}

func isFirstAppLaunch() -> Bool {
    assert(_firstAppLaunchStaticData.alreadyCalled == true, "[Error] Function setFirstAppLaunch wasn't called")
    return _firstAppLaunchStaticData.isFirstAppLaunch
}

然后，只需要在应用程序启动时调用setFirstAppLaunch()函数，并在需要检查是否已调用应用程序时调用isFirstAppLaunch()。

Answer 6

迅速

struct Pref {
    static let keyFirstRun = "PrefFirstRun"
    static var isFirstRun: Bool {
        get {
            return UserDefaults.standard.bool(forKey: keyFirstRun)
        }
        set {
            UserDefaults.standard.set(newValue, forKey: keyFirstRun)
        }
    }
}

在app launch上注册默认值：

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

        let prefs: [String:Any] = [
            Pref.keyFirstRun: true
            ...
        ]

        UserDefaults.standard.register(defaults: prefs)

应用终止的清晰价值：

func applicationWillTerminate(_ application: UIApplication) {
        Pref.isFirstRun = false

检查值：

 if Pref.isFirstRun {
    ... do whatever

Answer 7

在Swift 3,4中试试这个：

func isAppAlreadyLaunchedOnce()->Bool{
        let defaults = UserDefaults.standard

        if let isAppAlreadyLaunchedOnce = defaults.string(forKey: "isAppAlreadyLaunchedOnce"){
            print("App already launched : \(isAppAlreadyLaunchedOnce)")
            return true
        }else{
            defaults.set(true, forKey: "isAppAlreadyLaunchedOnce")
            print("App launched first time")
            return false
        }
    }

在Swift 2试试这个，

func isAppAlreadyLaunchedOnce()->Bool{
    let defaults = NSUserDefaults.standardUserDefaults()

    if let isAppAlreadyLaunchedOnce = defaults.stringForKey("isAppAlreadyLaunchedOnce"){
        print("App already launched : \(isAppAlreadyLaunchedOnce)")
        return true
    }else{
        defaults.setBool(true, forKey: "isAppAlreadyLaunchedOnce")
        print("App launched first time")
        return false
    }
}

更新： - 对于OBJ-C我使用这个，

+ (BOOL)isAppAlreadyLaunchedOnce {
    if ([[NSUserDefaults standardUserDefaults] boolForKey:@"isAppAlreadyLaunchedOnce"])
    {
        return true;
    }
    else
    {
        [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"isAppAlreadyLaunchedOnce"];
        [[NSUserDefaults standardUserDefaults] synchronize];
        return false;
    }
}

参考OBJ-C：https://stackoverflow.com/a/9964400/3411787

Answer 8

我为此目的写了一个小图书馆。它让我知道这是第一次启动，还是仅适用于此版本，以及用户安装的任何过去版本。它可以在github上作为Apache 2许可证下的cocoapod：GBVersionTracking

你只需在application:didFinishLaunching:withOptions:中调用它

[GBVersionTracking track];

然后检查这是否是第一次启动只是在任何地方调用它：

[GBVersionTracking isFirstLaunchEver];

同样地：

[GBVersionTracking isFirstLaunchForVersion];

[GBVersionTracking currentVersion];
[GBVersionTracking previousVersion];
[GBVersionTracking versionHistory];

Answer 9

Xcode 7和Swift 2.0的另一个想法是使用扩展

extension NSUserDefaults {
    func isFirstLaunch() -> Bool {
        if !NSUserDefaults.standardUserDefaults().boolForKey("HasAtLeastLaunchedOnce") {
            NSUserDefaults.standardUserDefaults().setBool(true, forKey: "HasAtLeastLaunchedOnce")
            NSUserDefaults.standardUserDefaults().synchronize()
            return true
        }
        return false
    }
}

现在，您可以在应用中的任何位置书写

if NSUserDefaults.standardUserDefaults().isFirstLaunch() {
    // do something on first launch
}

我个人更喜欢UIApplication的扩展，如下所示：

extension UIApplication {
    class func isFirstLaunch() -> Bool {
        if !NSUserDefaults.standardUserDefaults().boolForKey("HasAtLeastLaunchedOnce") {
            NSUserDefaults.standardUserDefaults().setBool(true, forKey: "HasAtLeastLaunchedOnce")
            NSUserDefaults.standardUserDefaults().synchronize()
            return true
        }
        return false
    }
}

因为函数调用更具描述性：

if UIApplication.isFirstLaunch() {
    // do something on first launch
}

Answer 10

您可以使用下面的静态方法实现它：

+ (BOOL)isFirstTime{
    static BOOL flag=NO;
    static BOOL result;

    if(!flag){
        if ([[NSUserDefaults standardUserDefaults] boolForKey:@"hasLaunchedOnce"]){
            result=NO;
        }else{
            [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"hasLaunchedOnce"];
            [[NSUserDefaults standardUserDefaults] synchronize];
            result=YES;
        }

        flag=YES;
    }
    return result;
}

Answer 11

对于swift 3.0

添加扩展名

    extension UIApplication {
        class func isFirstLaunch() -> Bool {
            if UserDefaults.standard.bool(forKey: "hasBeenLaunchedBeforeFlag") {
                UserDefaults.standard.set(true, forKey: "hasBeenLaunchedBeforeFlag")
                UserDefaults.standard.synchronize()
                return true
            }
            return false
        }
    }

然后在你的代码中

UIApplication.isFirstLaunch()

Answer 12

您需要在启动时保存一些内容，然后检查它是否存在。如果没有，这是第一次。 “Something”可以是文件，数据库条目，用户默认设置....

Answer 13

这样做非常简单，只需要六行代码。

在应用程序启动首选项中添加此代码或在您的应用程序第一次运行时可能需要测试其他任何其他位置将非常有用。

//These next six lines of code are the only ones required! The rest is just running      code when it's the first time.
//Declare an integer and a default.
NSUserDefaults *theDefaults;
int  launchCount;
//Set up the properties for the integer and default.
theDefaults = [NSUserDefaults standardUserDefaults];
launchCount = [theDefaults integerForKey:@"hasRun"] + 1;
[theDefaults setInteger:launchCount forKey:@"hasRun"];
[theDefaults synchronize];

//Log the amount of times the application has been run
NSLog(@"This application has been run %d amount of times", launchCount);

//Test if application is the first time running
if(launchCount == 1) {
    //Run your first launch code (Bring user to info/setup screen, etc.)
    NSLog(@"This is the first time this application has been run";
}

//Test if it has been run before
if(launchCount >= 2) {
    //Run new code if they have opened the app before (Bring user to home screen etc.
    NSLog(@"This application has been run before);
}

附：不要在首选项中使用bool只需坚持整数。未定义时，它们默认为零。

此外，[theDefaults synchronize];行不是必需的，但我发现当一个应用程序在数百个设备上运行数百次时，结果并不总是可靠的，此外，它是更好的做法。

Answer 14

在NSUserDefaults中存储一个bool密钥第一次不会你将它改为是并保持这样，直到应用程序删除或重新安装它将是第一次。

如何在iPhone上检测首次启动应用程序

问题描述投票：155回答：13

13个回答

NSUserDefaults + Macro

最新问题

如何在iPhone上检测首次启动应用程序

问题描述 投票：155回答：13

13个回答

NSUserDefaults + Macro

最新问题

问题描述投票：155回答：13