UITableViewCell Constraints Not Updated

Question

I have a custom UITableViewCell with UITextView, UICollectionView and UITableView inside. They have a 10 px space between. In some cases I have only UITextView, sometimes only collection view etc.

When no text - I have to move UICollection view up by 10 px. And If I have no text, tableView and collectionView it should be zero height.

- (void)configureMiddleWrapperState
{
    self.middleWrapperHasNote = self.noteTextView.text.length > 0;
    self.noteTextViewTopConstraint.constant = self.middleWrapperHasNote ? 7.f : 0.f;
    self.staffWrapperTopConstraint.constant = self.middleWrapperHasStaff ? 7.f : 0.f;
    self.tagsWrapperTopConstraint.constant = self.middleWrapperHasTags ? 7.f : 0.f;
    BOOL middleWrapperHasAtleastOne = self.middleWrapperHasNote || self.middleWrapperHasStaff ||
    self.middleWrapperHasTags;
    self.middleWrapperLastTenPixelSpaceConstraint.constant = middleWrapperHasAtleastOne ? 7.f : 0.f;
    [self setNeedsUpdateConstraints];
}

- (void)layoutSubviews
{
    [super layoutSubviews];
    [self setExcludedPaths];
    [self configureMiddleWrapperState];
}

The result isn't like expected: instead of one line. When only text is looks like expected.

Constraints become work only if I scroll up and down many times.

score 1 · Answer 1 · answered Jan 31 '17 at 13:32

1

try add

[self setNeedsLayout];

after

[self setNeedsUpdateConstraints];

answered Jan 31 '17 at 13:32

Moonkid

881
7
17

It will loop - setNeedsLayout forces [self layoutSubviews] – Artem Z. Jan 31 '17 at 13:37
So I think you have to move your logic somewere else. Maybe - (void) awakeFromNib will suit. – Moonkid Jan 31 '17 at 13:52
In awakeFromNib I don't know how to serve note text etc. Coz It didn't set in awakeFromNib – Artem Z. Jan 31 '17 at 13:54
Then create a new method that will configure cell with text and then update constraints - (void) configureWithText:(NSString *) newText; – Moonkid Jan 31 '17 at 14:03
I've found the issue. Coz my self.middleWrapperHasTags doesn't set correctly when reuse. By the way thanks for your help – Artem Z. Jan 31 '17 at 14:16

score 0 · Answer 2 · answered Jan 31 '17 at 14:16

0

I've found the issue. Coz my self.middleWrapperHasTags doesn't set correctly when reuse.

answered Jan 31 '17 at 14:16

Artem Z.

1,243
2
14
36

UITableViewCell Constraints Not Updated

2 Answers2