ios - 获取NSUserdefaults时出现问题

Question

我刚开始使用XCode进行编码，因此我尝试了很多方法来保存信息，但效果不佳。我用谷歌搜索，但仍然没有找到任何东西。

我采用了一个名为classNames的可变数组，并尝试保存文本字段(classField)中的信息，但该信息未与数组一起存储。

我还有另一个问题:我正在使用具有iOS 5.1的XCode，并且我已升级到具有iOS 6.1的Xcode，但是它给我一个错误，提示“连接中断”，并且所有按钮或功能都不起作用，但是它可以与具有iOS的XCode一起使用5.1
我需要帮助，谢谢。

#import "ViewController.h"

    @interface ViewController ()

    @end

    @implementation ViewController
    @synthesize orignalClass;
    @synthesize otherClassName;
    @synthesize editClassLabel;
    @synthesize displayLabel;
    @synthesize doSomethingButton;
    @synthesize classField;
    @synthesize testField;
    @synthesize classFieldFireTheme;
    @synthesize testFieldFireTheme;

    - (void)viewDidLoad
    {
        [super viewDidLoad];

        _classNames = [[NSMutableArray alloc] init];
        _classNames = [defaults objectForKey:@"classNames"];
        //NSLog(@" %@", [defaults objectForKey:@"classNames"]);


    }


- (void)viewDidUnload
{
    [self setDoSomethingButton:nil];
    [self setClassField:nil];
    [self setTestField:nil];
    [self setClassFieldFireTheme:nil];
    [self setTestFieldFireTheme:nil];
    [self setDisplayLabel:nil];
    [self setOrignalClass:nil];
    [self setEditClassLabel:nil];
    [self setOtherClassName:nil];
    [self setTestClass:nil];
    [super viewDidUnload];
    // Release any retained subviews of the main view.
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}

- (IBAction)classtextFieldDoneEdtiting:(id)sender {
    [sender resignFirstResponder];
}
- (IBAction)testClassTextFieldDoneEdtiting:(id)sender {
    [sender resignFirstResponder];
}
- (IBAction)TestTextFieldDoneEdtiting:(id)sender {
    [sender resignFirstResponder];
}
- (IBAction)ChangeClassTextFieldDoneEdtiting:(id)sender {
    [sender resignFirstResponder];
}
- (IBAction)ChangeClassToTextFieldDoneEdtiting:(id)sender {
    [sender resignFirstResponder];
}

- (IBAction)addClass:(id)sender {
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

    _classNames = [defaults objectForKey:@"classNames"];
    _classSize = [_classNames count];
    NSLog(@" %d", [_classNames count]);

    if(_classSize <=9){

        [_classNames insertObject: classField.text atIndex: [_classNames count]];
        NSLog(@"ClassNames#2::: %@", _classNames);
        NSLog(@"textfieldvalue::: %@", classField.text);
        [defaults setObject:_classNames forKey:@"classNames"];
        [[NSUserDefaults standardUserDefaults] synchronize];

        NSLog(@" %d", [_classNames count]);
        NSLog(@"ClassNames#3::: %@", _classNames);

   }else{
        displayLabel.text = @"You exceeded the limit of classes being stores!!!!";
   }

}

Answer 1

问题是，当数组从NSUserDefaults中出来时，它不是可变数组。即使您输入的是NSMutableArray，输出的还是普通的NSArray。您需要在该数组上使用mutableCopy使其可变。现在您可以存储到其中，然后将其放回NSUserDefaults中。