xcode 将 NSArray 添加到 NSMutableArray
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原文地址: http://stackoverflow.com/questions/9561480/
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Add NSArray To NSMutableArray
提问by JTApps
Thanks for you time and reading this. What I'm trying to do is figure out why this NSLogis telling me the NSArrayis always null, no matter what. I'm thinking that the problem is that I'm initiating the NSMutableArraywrong. Could you perhaps take a look and decide whether or not I did it right, and if at all possible give me a way to pass the array into the NSMutableArray?
感谢您抽出时间阅读本文。我想要做的是弄清楚为什么这NSLog告诉我NSArray不管怎样总是为空。我在想问题在于我开始NSMutableArray错误了。你能不能看看我是否做对了，如果可能的话，给我一种方法来将数组传递到NSMutableArray?
Thanks!
谢谢！
//Get Defaults
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSArray *favoriteArray = [[defaults objectForKey:@"favorites"] copy];
//Declares Mutable Array
self.favorites = [[NSMutableArray alloc] initWithObjects:favoriteArray, nil];
NSLog(@"array: %@", favorites);
UPDATE: I figured it out. It turns out you have to declare it with initWithArray rather than trying to add it as an object
更新：我想通了。事实证明，您必须使用 initWithArray 声明它，而不是尝试将其添加为对象
Solution:
解决方案：
- (void)viewDidLoad {
//Get Defaults
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSArray *favoriteArray = [[defaults objectForKey:@"favorites"] copy];
//Declares Mutable Array
self.favorites = [[NSMutableArray alloc] initWithArray:favoriteArray];
[super viewDidLoad];
}
回答by jroyce
The way to do this is using the arrayWithArray and here is how you do it:
这样做的方法是使用 arrayWithArray，这里是你如何做到的：
myNSMutableArray = [NSMutableArray arrayWithArray:myArray];
回答by UIAdam
Do you ever set an object in your user defaults for the "favorites" key?
你有没有在你的用户默认设置中为“收藏夹”键设置一个对象？
