Plist阅读怪异行为

Question

我正在使用一系列的代码来读取我的应用程序中的Plist文件，但是一个奇怪的行为开始了。这里是一个代码示例。

//init loading from PLIST here, and then associate value. 
NSString *pathString=[NSString stringWithFormat:@"%@Levels",targetWorld]; 
NSString *path = [[NSBundle mainBundle] pathForResource:pathString ofType:@"plist"]; 
NSString *levelNameNumber = [[NSString alloc] initWithFormat:targetLevel]; 

NSDictionary *levelsList = [[NSDictionary alloc] initWithContentsOfFile:path]; 
NSDictionary *level = [levelsList objectForKey:levelNameNumber]; 

NSEnumerator *levelFormations = [level objectEnumerator]; 

for(NSDictionary *worldSize in levelFormations) 
{ 
    worldWidth = [[worldSize objectForKey:@"width"] intValue]; 
    worldHeight = [[worldSize objectForKey:@"height"] intValue]; 

    NSLog(@"height is %d",worldHeight); 
    NSLog(@"width is %d",worldWidth); 

} 

[levelNameNumber release]; 
[levelsList release]; 

正如所示，我已经设置了NSLog以保持值的观察。这里是日志

2012-05-09 21:14:38.313 CapNTail[361:10a03] height is 344 
2012-05-09 21:14:38.315 CapNTail[361:10a03] width is 123 
2012-05-09 21:14:38.324 CapNTail[361:10a03] height is 0 
2012-05-09 21:14:38.326 CapNTail[361:10a03] width is 0 

他们似乎将自己重置为零。我能得到的最好的结果是它可能是for循环引起的，因为两个日志都被打印了两次（看起来像是运行第二个循环并重置它）。任何想法有什么不对？我的plist的

示例代码

<?xml version="1.0" encoding="UTF-8"?> 
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"  "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> 
<plist version="1.0"> 
<dict> 
<key>level1</key> 
<dict> 
    <key>worldSize</key> 
    <dict> 
     <key>width</key> 
     <integer>123</integer> 
     <key>height</key> 
     <integer>344</integer> 
    </dict> 
    <key>formation</key> 
    <dict> 
     <key>playerPosX</key> 
     <integer>0</integer> 
     <key>playerPosY</key> 
     <integer>0</integer> 

    </dict> 
</dict> 

Answer 1

你混淆快速列举与NSEnumerator。

使用NSEnumerator并使用while ((object = [enumerator nextObject])) {对其进行循环，或在level对象上使用快速枚举（无需制作NSEnumerator）。

要尝试一种策略（推荐），替换此：

NSEnumerator *levelFormations = [level objectEnumerator]; 

for(NSDictionary *worldSize in levelFormations) 
{ 
    worldWidth = [[worldSize objectForKey:@"width"] intValue]; 
    worldHeight = [[worldSize objectForKey:@"height"] intValue]; 

    NSLog(@"height is %d",worldHeight); 
    NSLog(@"width is %d",worldWidth); 

}

有：

for(NSDictionary *worldSize in level) 
{ 
    worldWidth = [[worldSize objectForKey:@"width"] intValue]; 
    worldHeight = [[worldSize objectForKey:@"height"] intValue]; 

    NSLog(@"height is %d",worldHeight); 
    NSLog(@"width is %d",worldWidth); 
} 

运作的？

参见this question.