标签不会相应改变

Question

我得到了以下问题：标签始终更改为标签9001中定义的标签。有人可以帮我找到我的错误吗？

ViewController.m：

- (IBAction)switch0:(id)sender 

{(button.tag = 9001); 
UIButton *buttonPressed = (UIButton *)sender; 
SecondViewController *second =[[SecondViewController alloc] initWithNibName:nil  bundle:nil]; 
[self presentModalViewController:second animated:YES]; 
second.buttonTag = buttonPressed.tag; 
} 


- (IBAction)switch2:(id)sender2 

{ (button2.tag = 9002); 
UIButton *buttonPressed = (UIButton *)sender2; 
SecondViewController *third =[[SecondViewController alloc] initWithNibName:nil bundle:nil]; 
[self presentModalViewController:third animated:YES]; 
second.buttonTag = buttonPressed.tag; 

}

SecondViewcontroller.m

- (void)viewDidLoad 
{ 
[super viewDidLoad]; 

if (buttonTag == 9001) { 
self.label1.text = [[NSString alloc] initWithFormat:@"Radnomtext"]; 
self.label2.text = [[NSString alloc] initWithFormat:@"Randomtext"]; 
self.label3.text = [[NSString alloc] initWithFormat:@"Randomtext?"]; 
} 
if (buttonTag == 9002) { 
self.label1.text = [[NSString alloc] initWithFormat:@"Radnomtext2"]; 
self.label2.text = [[NSString alloc] initWithFormat:@"Randomtext2"]; 
self.label3.text = [[NSString alloc] initWithFormat:@"Randomtext2?"]; 

Answer 1

这里有一个例子，你提出的观点两次我在这个例子中拿出模式：

- (IBAction)switch0:(id)sender 

    { 
    UIButton *buttonPressed = (UIButton *)sender; 
    SecondViewController *second =[[SecondViewController alloc] initWithNibName:nil  bundle:nil]; 

NSInteger tagToSet = 9001; 
    second.buttonTag = tagToSet;; 
     [self.navigationController pushViewController:second animated:YES]; 
    } 

并使用关键字切换不好。它是目标C中的保留字。

Answer 2

也许是因为您忘记关闭第一个if的结束括号？

if (buttonTag == 9001) { 
    self.label1.text = [[NSString alloc] initWithFormat:@"Radnomtext"]; 
    self.label2.text = [[NSString alloc] initWithFormat:@"Randomtext"]; 
    self.label3.text = [[NSString alloc] initWithFormat:@"Randomtext?"]; 
} // bracket supposed to be here 

if (buttonTag == 9002) { 

或者您可能将buttonTag设置为不正确的实例？

- (IBAction)switch2:(id)sender2 

{ 
UIButton *buttonPressed = (UIButton *)sender2; 
SecondViewController *third =[[SecondViewController alloc] initWithNibName:nil bundle:nil]; 
[self presentModalViewController:third animated:YES]; 
second.buttonTag = buttonPressed.tag; // supposed to be third? 
[self.navigationController pushViewController:third animated:YES]; 
(button2.tag = 9002); 
} 

而且是安全的，你应该presentModalViewController之前设置buttonTag。