- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view,typically from a nib.
ChildViewController *childviewcontroller = [[ChildViewController alloc] initWithNibName:@"ChildViewController" bundle:nil];
[self addChildViewController:childviewcontroller];
[self.view addSubview:childviewcontroller.view];
[childviewcontroller willMoveToParentViewController:self];
UIView *cview = [[UIView alloc] init];
cview = childviewcontroller.view;
[self.view removeConstraints:self.view.constraints];
NSDictionary *viewsDictionary = NSDictionaryOfVariableBindings(cview);
[self.view addConstraints:[NSLayoutConstraint
constraintsWithVisualFormat:@"H:|-[cview]-|"
options:0 metrics:nil
views:viewsDictionary]];
}
我想在父视图上添加childviewcontroller视图.添加后我设置了约束,但它对我不起作用.
我也收到这样的警告
2013-07-25 10:47:30.564 neenah[1105:c07] Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want.
Try this: (1) look at each constraint and try to figure out which you don't expect;
(2) find the code that added the unwanted constraint or constraints and fix it.
(Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't
understand,refer to the documentation for the UIView
property translatesAutoresizingMaskIntoConstraints)
(
"<NSLayoutConstraint:0x9256c90 H:|-(NSSpace(20))-[UIView:0x9256a00] (Names: '|':UIView:0x92557a0 )>","<NSAutoresizingMaskLayoutConstraint:0x755d690 h=--& v=--& H:[UIView:0x9256a00(320)]>","<NSAutoresizingMaskLayoutConstraint:0x755d5a0 h=--& v=--& UIView:0x9256a00.midX == + 160>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x9256c90 H:|-(NSSpace(20))-[UIView:0x9256a00] (Names: '|':UIView:0x92557a0 )>
Break on objc_exception_throw to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2013-07-25 10:47:30.567 neenah[1105:c07] Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand,refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints)
(
"<NSLayoutConstraint:0x9256bb0 H:[UIView:0x9256a00]-(NSSpace(20))-| (Names: '|':UIView:0x92557a0 )>","<NSAutoresizingMaskLayoutConstraint:0x7561690 h=--- v=--- H:[UIWindow:0x92527c0(320)]>","<NSAutoresizingMaskLayoutConstraint:0x755fe50 h=-&- v=-&- UIView:0x92557a0.width == UIWindow:0x92527c0.width>","<NSAutoresizingMaskLayoutConstraint:0x755d5a0 h=--& v=--& UIView:0x9256a00.midX == + 160>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x9256bb0 H:[UIView:0x9256a00]-(NSSpace(20))-| (Names: '|':UIView:0x92557a0 )>
Break on objc_exception_throw to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
解决方法
一些观察：
>你应该关闭translatesAutoresizingMaskIntoConstraints：
childviewcontroller.view.translatesAutoresizingMaskIntoConstraints = NO;
>您还应该定义垂直约束：
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-[cview]-|"
options:0
metrics:nil
views:viewsDictionary]];
>与您的问题无关,您不需要为cview创建[[UIView alloc] init].你马上放弃它.
>我不确定你为什么要删除self.view的约束. (我假设你这样做是因为你在测试时撕掉了你的头发.)你不必这样做.但如果你在这里有其他事情让你认为你需要这样做,那么让我们知道那是什么.
>添加子控制器时,调用didMoveToParentViewController,而不是willMoveToParentViewController. addChildViewController为您调用willMoveToParentViewController.你只需要didMove …再现.
从而：
- (void)viewDidLoad {
[super viewDidLoad];
// instantiate the view controller
ChildViewController *childViewController = [[ChildViewController alloc] initWithNibName:@"ChildViewController" bundle:nil];
// or you can instantiate using storyboard
//
// ChildViewController *child = [self.storyboard instantiateViewControllerWithIdentifier:@"ChildIdentifier"];
// now do the view controller containment calls to update the view controller hierarchy and add the view as appropriate
[self addChildViewController:childViewController];
childViewController.view.translatesAutoresizingMaskIntoConstraints = NO;
[self.view addSubview:childViewController.view];
[childViewController didMoveToParentViewController:self];
UIView *childView = childViewController.view;
NSDictionary *views = NSDictionaryOfVariableBindings(childView);
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-[childView]-|" options:0 metrics:nil views:views]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-[childView]-|" options:0 metrics:nil views:views]];
}
