小编Joh*_*oft的帖子

我用编程方式组装了一个简单的视图控制器,上面只有两个按钮.如果我去学校并为布局设置框架大小,那么一切都很好.但是,如果我对布局使用自动布局约束,则按钮显示完美,但它们不响应按下.他们甚至没有强调.我的loadview方法在下面的形式,使按钮不起作用.如果取消注释框架设置代码并添加注释的约束,则按钮开始按预期响应按下.有谁知道发生了什么事？我希望将我的代码库中所有旧的硬编码布局转换为基于约束的,但似乎是在第一个障碍下降.

- (void)loadView {
    self.view = [UIView new];
    self.view.translatesAutoresizingMaskIntoConstraints = NO;

    self.navigationItem.title = @"Landing Page";

    UIButton *buildExercisesButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    self.buildExercisesButton = buildExercisesButton;
//    buildExercisesButton.frame = CGRectMake(20, 312, 164, 44);
    self.buildExercisesButton.translatesAutoresizingMaskIntoConstraints = NO;
    [self.buildExercisesButton setTitle:@"Build Exercises" forState:UIControlStateNormal];
    [self.buildExercisesButton addTarget:self action:@selector(buildExercisesButtonPressed) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:self.buildExercisesButton];

    UIButton *organiseExercisesButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    self.organiseExercisesButton = organiseExercisesButton;
//    organiseExercisesButton.frame = CGRectMake(192, 312, 164, 44);
    self.organiseExercisesButton.translatesAutoresizingMaskIntoConstraints = NO;
    [self.organiseExercisesButton setTitle:@"Organise Exercises" forState:UIControlStateNormal];
    [self.organiseExercisesButton addTarget:self action:@selector(organiseExercisesButtonPressed) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:self.organiseExercisesButton];

    NSDictionary *variables = NSDictionaryOfVariableBindings(buildExercisesButton, organiseExercisesButton);
    NSArray *constraints =
            [NSLayoutConstraint …