Add some auto layout helper methods

Author: lobianco

Source/ALMenuCollectionViewCell.m

@@ -7,6 +7,8 @@
 
 #import "ALMenuCollectionViewCell.h"
 
+#import "UIView+ALLayout.h"
+
 #import "ALMenuItem.h"
 #import "ALUtils.h"
 
@@ -37,10 +39,7 @@ - (void)setButton:(UIView<ALMenuItem> *)button
     else
     {
         [self.contentView addSubview:button];
-        [button.leadingAnchor constraintEqualToAnchor:self.contentView.leadingAnchor].active = YES;
-        [button.topAnchor constraintEqualToAnchor:self.contentView.topAnchor].active = YES;
-        [button.trailingAnchor constraintEqualToAnchor:self.contentView.trailingAnchor].active = YES;
-        [button.bottomAnchor constraintEqualToAnchor:self.contentView.bottomAnchor].active = YES;
+        [button al_pinToSuperview];
     }
 
     _button = button;

Source/ALMenuViewController.m

@@ -194,10 +194,7 @@ - (void)buildView
     [self.collectionView registerClass:[ALMenuCollectionViewCell class] forCellWithReuseIdentifier:kCollectionViewCellReuseIdentifier];
 
     [self.containerView addSubview:self.collectionView];
-    [self.collectionView.leadingAnchor constraintEqualToAnchor:self.containerView.leadingAnchor].active = YES;
-    [self.collectionView.trailingAnchor constraintEqualToAnchor:self.containerView.trailingAnchor].active = YES;
-    [self.collectionView.topAnchor constraintEqualToAnchor:self.containerView.topAnchor].active = YES;
-    [self.collectionView.bottomAnchor constraintEqualToAnchor:self.containerView.bottomAnchor].active = YES;
+    [self.collectionView al_pinToSuperview];
 
     self.containerViewWidthConstraint = [self.containerView.widthAnchor constraintEqualToConstant:self.collectionView.contentSize.width];
     self.containerViewWidthConstraint.active = YES;

Source/UIView+ALLayout.h

@@ -13,4 +13,9 @@
 
 - (void)al_adjustPositionForNewAnchorPoint:(CGPoint)anchorPoint;
 
+#pragma mark - Auto Layout
+
+- (void)al_pinToSuperview;
+- (void)al_pinToView:(UIView *)view;
+
 @end

Source/UIView+ALLayout.m

@@ -30,4 +30,25 @@ - (void)al_adjustPositionForNewAnchorPoint:(CGPoint)anchorPoint
     self.layer.anchorPoint = anchorPoint;
 }
 
+#pragma mark - Auto Layout
+
+- (void)al_pinToSuperview
+{
+    [self al_pinToView:self.superview];
+}
+
+- (void)al_pinToView:(UIView *)view
+{
+    NSParameterAssert(view != nil);
+    
+    // forgetting to set this is the bane of my professional career
+    self.translatesAutoresizingMaskIntoConstraints = NO;
+
+    // then constrain
+    [self.leadingAnchor constraintEqualToAnchor:view.leadingAnchor].active = YES;
+    [self.trailingAnchor constraintEqualToAnchor:view.trailingAnchor].active = YES;
+    [self.topAnchor constraintEqualToAnchor:view.topAnchor].active = YES;
+    [self.bottomAnchor constraintEqualToAnchor:view.bottomAnchor].active = YES;
+}
+
 @end