Question

我正在尝试在UILabels上显示天气数据值（通过进行API调用获取），这是代码：

self.maxTempField.text = [NSString stringWithFormat:@"%@",vari[@"main"][@"\"temp_max\""]];
NSLog(@"Max Temp %@", vari[@"main"][@"temp_max"]);
self.atmosphericPresField.text = [NSString stringWithFormat:@"%@", vari[@"main"][@"pressure"]];
self.windSpeed.text = [NSString stringWithFormat:@"%@", vari[@"wind"][@"speed"]];
NSLog(@"Speeed of the wind %@", vari[@"wind"][@"speed"]);

我无法理解为什么标签没有更新。我还尝试将UILabel替换为UITextField，但问题仍然存在。以下是按钮操作的完整代码：

- (IBAction)moreProperties:(id)sender {
    UIStoryboard *refToStoryBoard = [UIStoryboard storyboardWithName:@"Main" bundle:[NSBundle mainBundle]];
    UIViewController *pointerToMoreValuesVC = [refToStoryBoard instantiateViewControllerWithIdentifier:@"MorePropertiesVC"];
    pointerToMoreValuesVC.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
    [self presentViewController:pointerToMoreValuesVC animated:YES completion:nil];
    self.noteLabel.text = @"Random Text";

    dispatch_async(dispatch_get_main_queue(), ^{

        self.maxTempField.text = [NSString stringWithFormat:@"%@",vari[@"main"][@"\"temp_max\""]];
        NSLog(@"Max Temp %@", vari[@"main"][@"temp_max"]);
        self.atmosphericPresField.text = [NSString stringWithFormat:@"%@", vari[@"main"][@"pressure"]];
        self.windSpeed.text = [NSString stringWithFormat:@"%@", vari[@"wind"][@"speed"]];
        NSLog(@"Speeed of the wind %@", vari[@"wind"][@"speed"]);
    });
}

我还检查了所有标签连接，它们很好。

Answer 1

首先创建一个名为WetherDetailVC的新类
现在你有两个文件.h和.m
将类WetherDetailVC分配给身份检查器中的视图控制器
如果您不想再次创建插座，只需切断所有插座（maxTempField，minTempField，...等）并将其全部粘贴在WetherDetailVC.h文件中

现在使用ViewController.h中的类对象访问所有插座

- (IBAction)moreProperties:(id)sender {
 UIStoryboard *refToStoryBoard = [UIStoryboard storyboardWithName:@"Main" bundle:[NSBundle mainBundle]];
 WetherDetail *pointerToMoreValuesVC = [refToStoryBoard instantiateViewControllerWithIdentifier:@"MorePropertiesVC"];
 pointerToMoreValuesVC.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
[self presentViewController:pointerToMoreValuesVC animated:YES completion:nil];
 pointerToMoreValuesVC.noteLabel.text = @"Random Text";
 pointerToMoreValuesVC.maxTempField.text = [NSString stringWithFormat:@"%@",vari[@"main"][@"temp_max"]];
 pointerToMoreValuesVC.atmosphericPressureField.text = [NSString stringWithFormat:@"%@", vari[@"main"][@"pressure"]];
  pointerToMoreValuesVC.windSpeedField.text = [NSString stringWithFormat:@"%@", vari[@"wind"][@"speed"]];
}

单击按钮时无法在UILabel上显示值

1 个答案: