Reputation: 2330
I'm working on a project that must support both iOS 8 and iOS 7.1. Right now I'm running into a problem that only appears on iOS 7.1 but works properly on iOS 8. I have a ViewController that contains a tableview and a custom view in the tableHeaderView. I'll post the code as follows. All constraints are added programatically.
//View Controller.
-(void)viewDidLoad
{
[super viewDidLoad];
self.commentsArray = [NSMutableArray new];
[self.commentsArray addObject:@"TEST"];
[self.commentsArray addObject:@"TEST"];
[self.commentsArray addObject:@"TEST"];
[self.commentsArray addObject:@"TEST"];
[self.commentsArray addObject:@"TEST"];
[self.commentsArray addObject:@"TEST"];
[self.view addSubview:self.masterTableView];
self.masterTableView.tableHeaderView = self.detailsView;
[self.view setNeedsUpdateConstraints];
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self.view layoutIfNeeded];
}
//Table view getter
- (UITableView *)masterTableView
{
if(!_masterTableView)
{
_masterTableView = [UITableView new];
_masterTableView.translatesAutoresizingMaskIntoConstraints = NO;
_masterTableView.backgroundColor = [UIColor greyColor];
_masterTableView.delegate = self;
_masterTableView.dataSource = self;
_masterTableView.separatorStyle = UITableViewCellSeparatorStyleNone;
_masterTableView.showsVerticalScrollIndicator = NO;
_masterTableView.separatorInset = UIEdgeInsetsZero;
}
return _masterTableView;
}
-(void)updateViewConstraints
{
NSDictionary *views = @{
@"table" : self.masterTableView,
@"details" : self.detailsView,
};
NSDictionary *metrics = @{
@"width" : @([UIScreen mainScreen].applicationFrame.size.width)
};
//Table view constraints
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[table]-0-|" options:0 metrics:0 views:views]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[table]-0-|" options:0 metrics:0 views:views]];
//Details View
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[details(width)]-0-|" options:0 metrics:metrics views:views]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[details]-0-|" options:0 metrics:metrics views:views]];
}
//Details View Getter
- (DetailsView *)detailsView
{
if(!_detailsView)
{
_detailsView = [[DetailsView alloc]initWithFrame:CGRectMake(0, 0, 0, 100)];
_detailsView.backgroundColor = [UIColor orangeColor];
return _detailsView;
}
Now the details view contains some basic subviews which all derive from a UIView and the details view itself derives from a more general super class. I'll post the code as follows.
//Parent View
@interface ParentView (): UIView
- (instancetype)init
{
self = [super init];
if (self)
{
[self setupViews];
}
return self;
}
- (void)setupViews
{
[self addSubview:self.publishedTimeView];
}
- (void)updateConstraints
{
NSDictionary *views = @{
@"time" : self.publishedTimeView,
};
// Header with published video time
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[time]-10-|" options:0 metrics:0 views:views]];
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[time(11)]" options:0 metrics:0 views:views]];
[super updateConstraints];
}
//Getter for the timePublished view added to the detail view. Will not post all its related code for //the sake of brevity.
- (TimePublishedDetailView *)publishedTimeView
{
if(!_publishedTimeView)
{
_publishedTimeView = [TimePublishedDetailView new];
_publishedTimeView.translatesAutoresizingMaskIntoConstraints = NO;
}
return _publishedTimeView;
}
//Child View (or the detailsView) of the view controller.
@interface DetailsView : ParentView
@implementation RecordingDetailsView
- (void)updateConstraints
{
NSDictionary *views = @{
@"time" : self.publishedTimeView,
};
//Vertical alignment of all views
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[time]" options:0 metrics:nil views:views]];
[super updateConstraints];
}
- (void)setModel:(DetailViewModel *)model
{
self.publishedTimeView.date = model.dateTime;
[self setNeedsUpdateConstraints];
[self layoutSubviews];
}
Now on iOS 8 this looks like this:
However on iOS 7.1 this will crash with this error message:
"Exception: Auto layout still required after executing -layoutSubviews. UITableView's implementation of -layoutSubviews needs to call super"
I've googled this and played around with the code in my layout calls to see if I can remedy the problem but so far have been unsuccessful. If anyone could post some tips or advice on how to fix this I would really appreciate it.
Upvotes: 1
Views: 352
Reputation: 3215
I know this question is old, but I ran into a similar problem recently and after a lot of Googling, trying and failing I made it work with the help of this answer and a few changes.
Just add this category to your project and call [UITableView fixLayoutSubviewsMethod];
only once (I recommend inside AppDelegate
).
#import <objc/runtime.h>
#import <objc/message.h>
@implementation UITableView (FixUITableViewAutolayoutIHope)
+ (void)fixLayoutSubviewsMethod
{
Method existing = class_getInstanceMethod(self, @selector(layoutSubviews));
Method new = class_getInstanceMethod(self, @selector(_autolayout_replacementLayoutSubviews));
method_exchangeImplementations(existing, new);
}
- (void)_autolayout_replacementLayoutSubviews
{
[super layoutSubviews];
[self _autolayout_replacementLayoutSubviews]; // not recursive due to method swizzling
[super layoutSubviews];
}
@end
Upvotes: 2