Install/Uninstall constraint programmatically

ios objective-c autolayout interface-builder nslayoutconstraint
Eric picture Eric · May 28, 2015 · Viewed 12.3k times · Source

Is there a way to install and uninstall an Xcode interface builder constraint programmatically?

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Answer

A C picture A C · May 28, 2015

Connect the IBOutlet for the NSLayoutConstraint by CTRL+click the constraint and drag it to the viewController (for ex. @property (weak, nonatomic) IBOutlet NSLayoutConstraint *constraint;).

For removing the constraint: 

[self.view removeConstraint:constraint]

for installing the constraint:

[self.view addConstraint:constraint]

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