Question

我打算开设一个应用商店，我想免费为现有用户提供一些商品。

我想发布一个更新，它会在第一次使用应用程序时存储一些信息，然后发布“真实”更新，看看之前是否购买了应用程序，但是，很可能不是每个人都会选择第一次更新。

那么，有没有办法找出用户何时首次安装~~（或已使用）~~应用程序？

更新：

感谢您的回答，但我应该不那么模糊：

我正在寻找原生电话/类似的事情。由于该应用已经在商店，我还没有设置任何内容来存储第一个版本的数据，如果所有用户在第二次更新之前抓取它，更新将帮助我做我想要的发布：无法区分新用户和错过中间更新的新用户，并且刚刚更新到最新用户。

Answer 1

要获取安装日期，请检查Documents文件夹的创建日期。

NSURL* urlToDocumentsFolder = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
__autoreleasing NSError *error;
NSDate *installDate = [[[NSFileManager defaultManager] attributesOfItemAtPath:urlToDocumentsFolder.path error:&error] objectForKey:NSFileCreationDate];

NSLog(@"This app was installed by the user on %@", installDate);

要获取上次应用更新的日期，请检查应用包本身的修改日期

NSString* pathToInfoPlist = [[NSBundle mainBundle] pathForResource:@"Info" ofType:@"plist"];
NSString* pathToAppBundle = [pathToInfoPlist stringByDeletingLastPathComponent];
NSDate *updateDate  = [[[NSFileManager defaultManager] attributesOfItemAtPath:pathToAppBundle error:&error] objectForKey:NSFileModificationDate];

NSLog(@"This app was updated by the user on %@", updateDate);

Answer 2

NSDate *installDate = [[NSUserDefaults standardUserDefaults]objectForKey:@"installDate"];

if (!installDate) {
    //no date is present
    //this app has not run before
    NSDate *todaysDate = [NSDate date];
    [[NSUserDefaults standardUserDefaults]setObject:todaysDate forKey:@"installDate"];
    [[NSUserDefaults standardUserDefaults]synchronize];

    //nothing more to do?
} else {
    //date is found
    NSDate *todaysDate = [NSDate date];
    //compare todaysDate with installDate
    //if enough time has passed, yada yada,
    //apply updates, etc.
}

Answer 3

我的解决方案是检查应用包中其中一个文件的上次修改日期。

NSString *sourceFile = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"Icon.png"];

NSDate *lastModif = [[[NSFileManager defaultManager] attributesOfItemAtPath:sourceFile error:&err] objectForKey:NSFileModificationDate];

Answer 4

我建议您在首次启动时设置日期并将其存储在NSUserDefaults中。在发布时查找日期，如果不存在，请设置它。如果是，请进行一些日期比较，并根据您的计划处理其余的日期。

Answer 5

回答看看人们是否可以找到这个问题。它似乎比我在这里找到的其他人更长，但它确实告诉你应用程序是否自更新后第一次运行（为此你必须更改你的info.plist）......

// called during startup, compares the current version string with the one stored on standardUserDefaults
+ (BOOL)isFreshInstallOrUpdate
{
    BOOL ret = YES;
    NSString *cfBundleVersionStored = [[NSUserDefaults standardUserDefaults] objectForKey:@"CFBundleVersion"];
    NSString *cfBundleShortVersionStringStored = [[NSUserDefaults standardUserDefaults] objectForKey:@"CFBundleShortVersionString"];

    NSString *cfBundleVersionPlist = [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleVersion"];;
    NSString *cfBundleShortVersionStringPlist = [[NSBundle mainBundle] objectForInfoDictionaryKey:
                                                 @"CFBundleShortVersionString"];

    ret = [cfBundleVersionPlist compare:cfBundleVersionStored] != NSOrderedSame ||
    [cfBundleShortVersionStringPlist compare:cfBundleShortVersionStringStored] != NSOrderedSame;

    return ret;
}


// calling this once will necessarily cause isFreshInstall to return false
+ (void)setStoredVersionNumber
{
    NSString *cfBundleVersionPlist = [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleVersion"];
    NSString *cfBundleShortVersionStringPlist = [[NSBundle mainBundle] objectForInfoDictionaryKey:
                                                 @"CFBundleShortVersionString"];

    [[NSUserDefaults standardUserDefaults] setObject:cfBundleVersionPlist forKey:@"CFBundleVersion"];
    [[NSUserDefaults standardUserDefaults] setObject:cfBundleShortVersionStringPlist forKey:@"CFBundleShortVersionString"];

    // setting now as unfresh!
    [[NSUserDefaults standardUserDefaults] synchronize];
}

Answer 6

应用构建日期：

public var appBuildDate: Date {
  if let path = Bundle.main.path(forResource: "Info", ofType: "plist") {
    if let createdDate = try! FileManager.default.attributesOfItem(atPath: path)[.creationDate] as? Date {
      return createdDate
    }
  }
  return Date() // Should never execute
}

应用安装日期：

public var appInstallDate: Date {
  if let documentsFolder = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last {
    if let installDate = try! FileManager.default.attributesOfItem(atPath: documentsFolder.path)[.creationDate] as? Date {
      return installDate
    }
  }
  return Date() // Should never execute
}

Answer 7

您可以随时检查服务器。以前使用UDID很简单，但由于这些已被弃用，您已经创建了一个UUID（CFUUIDCreate（）或类似的东西:)）并将其存储在钥匙串中，即使用户将删除密钥链，存储在钥匙串中的每个信息都将保持不变。应用程序并在一年左右后再次安装...我发现这个articke在第一次处理钥匙串值时非常有用： http://useyourloaf.com/blog/2010/3/29/simple-iphone-keychain-access.html

Answer 8

Swift solution:

let urlToDocumentsFolder = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask).last!
//installDate is NSDate of install
let installDate = (try! NSFileManager.defaultManager().attributesOfItemAtPath(urlToDocumentsFolder.path!)[NSFileCreationDate])
print("This app was installed by the user on \(installDate)")

Answer 9

使用Documents目录的创建日期是迄今为止最好的解决方案。在Swift 4.2中复制它

var inferredDateInstalledOn: Date? {
    guard
        let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last,
        let attributes = try? FileManager.default.attributesOfItem(atPath: documentsURL.path),
        else { return nil }
    return attributes[.creationDate] as? Date
}

Answer 10

这是一种更安全的方法，无需进行强制尝试和强制解包，并进行更新以适应 SWIFT 5 ：

if
    let urlToDocumentsFolder = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last,
    let installDateAny = (try? FileManager.default.attributesOfItem(atPath: urlToDocumentsFolder.path)[.creationDate]),
    let installDate = installDateAny as? Date
{
    print("This app was installed by the user on \(installDate)")
}

如何确定第一次安装或使用应用程序的日期？

10 个答案: