对象计数(0)与键计数(1)不同

时间:2013-01-19 21:00:35

标签: objective-c object key plist nsdictionary

一个错误不断弹出,表示对象的键数不同,然后程序不断崩溃。

以下代码是令人质疑的问题。

-(void)saveData //error is in here
{

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
//get documents path
NSString *documentsPath = [paths objectAtIndex:0];
//get the path to our Data/plist file
NSString *plistPath = [documentsPath stringByAppendingPathComponent:@"Data.plist"];

//set the variables to the values in the text fields
self.topScores = highScore.text;

//create dictionary with values in UITextFields
NSDictionary *plistDict = [NSDictionary dictionaryWithObjects: [NSArray arrayWithObjects: topScores, nil] forKeys:[NSArray arrayWithObjects: @"bestScore", nil]];

NSString *error = nil;
//create NSData from dictionary
NSData *plistData = [NSPropertyListSerialization dataFromPropertyList: plistDict format: NSPropertyListXMLFormat_v1_0 errorDescription: &error];

//check if plist data exists
if (plistData)
{
    //write plistData to our Data.plist file
    [plistData writeToFile:plistPath atomically:YES];
}
else
{
    NSLog(@"Error in saveData: %@", error);
    [error release];
 }
}

代码有效,但随后它在这里崩溃

         if (newTopScore > [topScores intValue]) 
        {
            topScores = ([NSString stringWithFormat:@"%i", newTopScore]); 
        }

        highScore.alpha = 1; 

    [self saveData];

1 个答案:

答案 0 :(得分:2)

必须是这一行:

NSDictionary *plistDict = [NSDictionary dictionaryWithObjects: [NSArray arrayWithObjects: topScores, nil] forKeys:[NSArray arrayWithObjects: @"bestScore", nil]];

并且必须是topScores为nil,这意味着objects数组的大小为0,而keys数组的大小为1。

您需要找出topScores为零的原因。

例如,尝试运行此代码:

NSDictionary *plistDict = [NSDictionary dictionaryWithObjects:@[] 
                                                      forKeys:@[@"bestScore"]];

你会得到:

  

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSDictionary initWithObjects:forKeys:]: count of objects (0) differs from count of keys (1)'