Acessar restrição de layout automático programaticamente

Question

Dec 13, 2013, 06:10 PM

Acessar restrição de layout automático programaticamente

Eu tenho uma visão que tem um monte de subviews, vou me referir a essas visões como superview, subview A, subview B, subview C, etc.

Então, eu preciso acessar a restrição de espaço à direita que eu configurei no subView A para superviá-lo e modificá-lo. Essa restrição apareceria em superview.constraints.

No entanto, todas as subvisualizações têm restrições de espaço entre o início e o final.

Então, se eu registrar superview.constraints, ficaria assim:

<__NSArrayM 0xac744e0>(
<NSLayoutConstraint:0x98f3500 H:|-(0)-[UILabel:0x98f2190]   (Names:     '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3540 H:[UILabel:0x98f2190]-(20)-|   (Names:   '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3580 V:[UILabel:0x98f2190]-(-4)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f35c0 V:[UIView:0x98f2770]-(42)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3600 H:[UIView:0x98f2770]-(20)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3640 H:|-(0)-[UIView:0x98f2770]   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3680 H:|-(0)-[UIView:0x98f2610]   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f36c0 H:[UIView:0x98f2610]-(0)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3700 V:[UIView:0x98f2610]-(1)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3740 V:[UIView:0x98f2920]-(107)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3780 H:[UIView:0x98f2920]-(20)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f37c0 H:|-(0)-[UIView:0x98f2920]   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3800 H:[UIButton:0x98f19c0]-(178)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3840 V:[UIButton:0x98f19c0]-(55)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3880 H:|-(0)-[UILabel:0x98f2a80]   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f38c0 V:[UILabel:0x98f2a80]-(109)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3900 H:[UILabel:0x98f2a80]-(20)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3940 H:|-(171)-[UIButton:0x98f2ff0]   (Names: '|':HeaderReusableView:0x98f1f40 )>,
<NSLayoutConstraint:0x98f3980 V:[UIButton:0x98f2ff0]-(55)-|   (Names: '|':HeaderReusableView:0x98f1f40 )>

)

Eu não tenho idéia de qual restrição é a que eu quero.