仅在应用程序获得更新时重置特定的 NSUserDefaults 键

Question

我有两个 NSUserDefaults 键：第一个是与显示小介绍窗口相关的一个，第二个是与前 3 个会话更改 tableView 中的单元格背景颜色相关的一个。

现在，当我更新我的应用程序时，我希望重置第二个键，以便为前 3 个会话显示不同的单元格背景颜色。

这是我的应用委托中的代码：

[[NSUserDefaults standardUserDefaults] setObject: @"1.3.5" forKey:@"lastVer"];//in memory
    NSString *lastVersion = [[NSUserDefaults standardUserDefaults] objectForKey:@"lastVer"];
    NSString *version = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];

    NSLog(@"**** Version: %@",version);

    NSNumber *runNumber = [[NSUserDefaults standardUserDefaults] objectForKey:@"runNum"]; 
   if(![lastVersion isEqualToString: version]){
        NSNumber *runNumber = [NSNumber numberWithInt:0]; 
        [[NSUserDefaults standardUserDefaults] setObject:runNumber forKey:@"runNum"]; 
    }
    else { 
        [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:([runNumber intValue] + 1)] forKey:@"runNum"]; 
        NSLog(@"This is Run Number: %d", [runNumber intValue]);    
    }

    if (runNumber == [NSNumber numberWithInt:0]){
       [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:([runNumber intValue] + 1)] forKey:@"runNum"]; 
        NSLog(@"Run number: %d", [runNumber intValue]);    
    }

（注意：runNumber 是存储 3 个会话的单元格背景颜色的键）

它检查 lastVersion 是否等于 bundle 版本，并重置 runNum 的键（给它值 0）。然后，如果runNum为0，则增加runNumbers。

但是有一个问题！

当 lastVersion 与版本不同时，它会重置密钥，但我不知道如何再次增加 runNum，而无需再次重置运行次数，因为每次打开应用程序时都会重置 runNum！

即

lastVersion = 1.3.4
version = 1.3.5
if lastVersion is different from version, then runNum == 0
and if runNum == 0, runNum = runNum + 1
//CLOSING AND REOPENING THE APP
runNum = 0 
runNum = runNum +1
//CLOSING AND REOPENING THE APP
runNum = 0
runNum = runNum + 1
//and so on..

当我关闭并重新打开应用程序时，runNum 键再次为 0！

如何只重置一次 runNum 键，然后再增加一次？

编辑

我做了以下更改：

NSString *lastVersion = [[NSUserDefaults standardUserDefaults] objectForKey:@"lastVer"]; 

    // get the current bundle version. 
    NSString *currentVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"]; 


    NSLog(@"Last Version: %@, New Version: %@", lastVersion, currentVersion); 

    NSNumber *runNumber = [[NSUserDefaults standardUserDefaults] objectForKey:@"runNum"]; 
    NSInteger runNumberValue = [runNumber integerValue]; 


    if(![lastVersion isEqualToString: currentVersion]){ 
        NSLog(@"Last Version and Version are not same."); 
        NSNumber *runNumber = [NSNumber numberWithInt:0]; 
        [[NSUserDefaults standardUserDefaults] setObject:runNumber forKey:@"runNum"]; 
        [[NSUserDefaults standardUserDefaults] setObject:currentVersion forKey:@"lastVer"]; 
        NSLog(@"last Version is: %@",lastVersion);

    } 
    else { 
        NSLog(@"Last Version and Version are same."); 
        NSInteger newRunNumberValue = runNumberValue++; 
        if(newRunNumberValue > 2) { 
            newRunNumberValue = 0; 
        } 
        [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:newRunNumberValue] forKey:@"runNum"]; 
    }

这是在前 3 个会话中使单元格背景发生变化的代码：

    NSString *lastVersion = [[NSUserDefaults standardUserDefaults] objectForKey:@"lastVer"]; 

// get the current bundle version. 
NSString *currentVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"]; 

NSLog(@"Last Version: %@, New Version: %@", lastVersion, currentVersion); 

NSNumber *runNumber = [[NSUserDefaults standardUserDefaults] objectForKey:@"runNum"]; 

if (!runNumber) { 
    NSLog(@"**** Resetting Run Number to zero ****"); 
    NSNumber *runNumber = [NSNumber numberWithInt:0]; 
    [[NSUserDefaults standardUserDefaults] setObject:runNumber forKey:@"runNum"]; 
} else { 
    [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:([runNumber intValue] + 1)] forKey:@"runNum"]; 
    NSLog(@"This is Run Number: %d", [runNumber intValue]); 
} 


if(![lastVersion isEqualToString: currentVersion]){ 
    NSLog(@"Last Version and Version are not same."); 
    [[NSUserDefaults standardUserDefaults] setObject:currentVersion forKey:@"lastVer"]; 
    NSLog(@"last Version is: %@",lastVersion);
    //What should i do here to make the updated app show the different cells background?
} 
else { 
    NSLog(@"Last Version and Version are same."); 
    //What should i do here to make the updated app show the different cells background?
}

现在：当用户第一次下载应用程序（3 个会话）和用户更新应用程序时（即使在 N 个会话之后），如何让应用程序显示不同的单元格背景？我被困在这里了。

有什么想法吗？

Answer 1

我自己解决了！

 if(![lastVersion isEqualToString: currentVersion]){ 
        NSLog(@"Last Version and Version are not same."); 
        [[NSUserDefaults standardUserDefaults] setObject:currentVersion forKey:@"lastVer"]; 
        NSLog(@"last Version is: %@",lastVersion);
        NSNumber *runNumber = [NSNumber numberWithInt:0]; 
        [[NSUserDefaults standardUserDefaults] setObject:runNumber forKey:@"runNum"]; 
        NSLog(@"runNumber is: %d",[runNumber intValue]);

    } 
    else { 
        NSLog(@"Last Version and Version are same."); 
        [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:([runNumber intValue] + 1)] forKey:@"runNum"]; 
        NSLog(@" Run Number: %d", [runNumber intValue]);    
    }

Answer 2

当最后一个版本不等于当前版本时，您应该重置运行号。这将在您的新版本的第一次运行中。因此，在将用户默认值更新为捆绑包中的版本号之前，请在此时重置运行号。

Answer 3

虽然您的问题不是很清楚，但我只是根据我能理解的内容提供帮助。请编辑您的问题，以便更清楚地描述您的问题。

你能记录下你的 NSString *version 的值吗？

即紧随其后：

NSString *version = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];

放一个

NSLog(@"version %@", version);

这应该确保您的

if([lastVersion isEqualToString: version]){ 
...
}

执行与否。

此外，您不必为了更新它而从 NSUserDefaults 中删除密钥。您可以安全地从代码中删除此行：

[[NSUserDefaults standardUserDefaults] removeObjectForKey:@"runNum"];

只需进行这些更改，让我知道它是否有效。