Question

我想将LoginView中的textfield值传递给uploadview，但UserLogin1总是为NULL（0x000000）这是我的代码： loginvuew.h

@property (nonatomic,retain) IBOutlet UITextField *username;

loginview.m

-(IBAction)LoginButton:(id)sender{
 uploadview= [[UploadTab alloc] initWithFrame:CGRectMake(0,0,0,0) andUsertring:username.text];
}

uploadview.h

@property (nonatomic, copy) NSString *UserLogin1;
- (id)initWithFrame:(CGRect)frame andUsertring:(NSString *)strUser;

uploadview.m

- (id)initWithFrame:(CGRect)frame andUsertring:(NSString *)strUser
{
    if (self) {
        UserLogin1=[[NSString alloc] init];
        UserLogin1 = strUser;

    }
    return self;
}

- (void)viewDidLoad
{
 NSLog(@"User login: %@",UserLogin1);
        self.navigationItem.title = [NSString stringWithFormat: @"Hello, %@",UserLogin1];

}

当在initWithFrame（）中运行时，字符串传递正确但在ViewDidLoad中不正确。并且UserLogin1变量始终为0x00000。你有sugesstions？ Thansk提前

Answer 1

你搞砸了我想的事情。什么类是UploadTab？视图没有方法viewDidload！这是UIViewController的一个。如果它是ViewController，那么你应该使用initWithNibName正确分配它：bundle或smth就是这样。添加：您的代码缺少实际的alloc-init方法

- (id)initWithFrame:(CGRect)frame andUsertring:(NSString *)strUser
{
    // self is nil here! It is in almost every cases done like self = [[super alloc] initBlaBla]
    if (self) {
        UserLogin1=[[NSString alloc] init];
        UserLogin1 = strUser;

    }
    return self;
}

无法将文本字段的值传递给ios中的其他viewcontroller

1 个答案: