Question

我正在尝试实际测试如何使用Xcode现在提供的单一视图模板来硬编码接口。

我给了AppDelegate.h一个ivar和UILabel * titleLabel的属性;我的AppDelegate.m代码在 - （void）中声明完成启动：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    

    // Override point for customization after application launch.

    // Set the view controller as the window's root view controller and display.
    self.window.rootViewController = self.viewController;
    [self.window makeKeyAndVisible];

    return YES;

    UIButton *button                  = [UIButton buttonWithType: UIButtonTypeRoundedRect];
    button.titleLabel.font            = [UIFont systemFontOfSize: 12];
    button.titleLabel.lineBreakMode   = UILineBreakModeTailTruncation;
    button.titleLabel.shadowOffset    = CGSizeMake (1.0, 0.0);


    [self.window addSubview: button];

}

我获得了成功的编译，但屏幕上没有绘制按钮 - 我只是在模拟器中运行标准空白模板。我如何得到它？

Answer 1

您的窗口似乎未初始化，并且您的功能过早返回。试试这个：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    

    // Override point for customization after application launch.
    self.window = [[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
    // Set the view controller as the window's root view controller and display.
    self.window.rootViewController = self.viewController;
    [self.window makeKeyAndVisible];

    UIButton *button                  = [UIButton buttonWithType: UIButtonTypeRoundedRect];
button.titleLabel.font            = [UIFont systemFontOfSize: 12];
button.titleLabel.lineBreakMode   = UILineBreakModeTailTruncation;
button.titleLabel.shadowOffset    = CGSizeMake (1.0, 0.0);


[self.window addSubview: button];
return YES;
}

请记住return会立即退出某个函数，并且不会执行其下面的任何代码。

我的UIButton没有被吸引到屏幕上

1 个答案: