RTimal/UIView-Autolayout

A Simple Autolayout category that adds constraints to a specified ancestor view.

#Layout constraints are in the format:

###view1.attribute1 = view2.attribute2 * multiplier + constant or
###y = mx + b
###Where '=' can be replaced by >= or <=

###This category emulates that structure

Works in iOS 7

self.view.backgroundColor = [UIColor greenColor];
//Frames become irrelevant
UIView* view1 = [[UIView alloc] initWithFrame:CGRectZero];
view1.backgroundColor = [UIColor redColor];


//Frames become irrelevant
UIView* view2 = [[UIView alloc] initWithFrame:CGRectZero];
view2.backgroundColor = [UIColor blueColor];
[self.view addSubview:view1];
[self.view addSubview:view2];


view2.layer.cornerRadius = 10.f;

//You must add a width and height , as well as a position constraint. The category sets translatesAutoResizingMask = NO and adds the constraint to the specified ancestor view.


//Red background
[view1 constrainWithAttribute:NSLayoutAttributeLeft
					relatedBy:NSLayoutRelationEqual
						view2:self.view
					attribute:NSLayoutAttributeLeft
				 multipliedBy:1.f plus:0.f
				  addedToView:self.view];

[view1 constrainWithAttribute:NSLayoutAttributeTop
					relatedBy:NSLayoutRelationEqual
						view2:self.view attribute:NSLayoutAttributeTop
				 multipliedBy:1.f plus:0.f addedToView:self.view];

[view1 constrainWithAttribute:NSLayoutAttributeWidth
					relatedBy:NSLayoutRelationEqual
						view2:self.view attribute:NSLayoutAttributeWidth
				 multipliedBy:1.f plus:0.f
				  addedToView:self.view];

[view1 constrainWithAttribute:NSLayoutAttributeHeight
					relatedBy:NSLayoutRelationEqual
						view2:self.view
					attribute:NSLayoutAttributeHeight
				 multipliedBy:1.f plus:0.f addedToView:self.view];



//Blue square
[view2 constrainToSize:CGSizeMake(100.f, 100.f)];

[view2 constrainWithAttribute:NSLayoutAttributeCenterX
					relatedBy:NSLayoutRelationEqual
						view2:view1 attribute:NSLayoutAttributeCenterX
				 multipliedBy:1.f
						 plus:00.f
				  addedToView:self.view];

[view2 constrainWithAttribute:NSLayoutAttributeCenterY
					relatedBy:NSLayoutRelationEqual
						view2:view1 attribute:NSLayoutAttributeCenterY
				 multipliedBy:1.f plus:0.f addedToView:self.view];