Adds NGModalPresentation category on UIViewController which provides an easy API to present view controllers modally not in full screen. Adds NGModalTransitioningDelegate and NGModalAnimationController which are used by NGModalPresentation category.

ModalPresentation.xcodeproj/project.pbxproj

@@ -15,6 +15,9 @@
 		2E4683BB19DFE437001ECA2E /* LaunchScreen.xib in Resources */ = {isa = PBXBuildFile; fileRef = 2E4683B919DFE437001ECA2E /* LaunchScreen.xib */; };
 		2E4683C719DFE438001ECA2E /* ModalPresentationTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 2E4683C619DFE438001ECA2E /* ModalPresentationTests.m */; };
 		2E4683D219DFE60D001ECA2E /* SampleViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 2E4683D119DFE60D001ECA2E /* SampleViewController.m */; };
+		2E4683D619DFEFD3001ECA2E /* UIViewController+NGModalPresentation.m in Sources */ = {isa = PBXBuildFile; fileRef = 2E4683D519DFEFD3001ECA2E /* UIViewController+NGModalPresentation.m */; };
+		2E4683D919DFF197001ECA2E /* NGModalTransitioningDelegate.m in Sources */ = {isa = PBXBuildFile; fileRef = 2E4683D819DFF197001ECA2E /* NGModalTransitioningDelegate.m */; };
+		2E4683DC19DFF39D001ECA2E /* NGModalAnimationController.m in Sources */ = {isa = PBXBuildFile; fileRef = 2E4683DB19DFF39D001ECA2E /* NGModalAnimationController.m */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -43,6 +46,12 @@
 		2E4683C619DFE438001ECA2E /* ModalPresentationTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ModalPresentationTests.m; sourceTree = "<group>"; };
 		2E4683D019DFE60D001ECA2E /* SampleViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SampleViewController.h; sourceTree = "<group>"; };
 		2E4683D119DFE60D001ECA2E /* SampleViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SampleViewController.m; sourceTree = "<group>"; };
+		2E4683D419DFEFD3001ECA2E /* UIViewController+NGModalPresentation.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "UIViewController+NGModalPresentation.h"; sourceTree = "<group>"; };
+		2E4683D519DFEFD3001ECA2E /* UIViewController+NGModalPresentation.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "UIViewController+NGModalPresentation.m"; sourceTree = "<group>"; };
+		2E4683D719DFF197001ECA2E /* NGModalTransitioningDelegate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = NGModalTransitioningDelegate.h; sourceTree = "<group>"; };
+		2E4683D819DFF197001ECA2E /* NGModalTransitioningDelegate.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = NGModalTransitioningDelegate.m; sourceTree = "<group>"; };
+		2E4683DA19DFF39D001ECA2E /* NGModalAnimationController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = NGModalAnimationController.h; sourceTree = "<group>"; };
+		2E4683DB19DFF39D001ECA2E /* NGModalAnimationController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = NGModalAnimationController.m; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -94,6 +103,7 @@
 				2E4683AA19DFE437001ECA2E /* Supporting Files */,
 				2E4683D019DFE60D001ECA2E /* SampleViewController.h */,
 				2E4683D119DFE60D001ECA2E /* SampleViewController.m */,
+				2E4683D319DFEF2F001ECA2E /* Custom Modal Presentation */,
 			);
 			path = ModalPresentation;
 			sourceTree = "<group>";
@@ -124,6 +134,19 @@
 			name = "Supporting Files";
 			sourceTree = "<group>";
 		};
+		2E4683D319DFEF2F001ECA2E /* Custom Modal Presentation */ = {
+			isa = PBXGroup;
+			children = (
+				2E4683D419DFEFD3001ECA2E /* UIViewController+NGModalPresentation.h */,
+				2E4683D519DFEFD3001ECA2E /* UIViewController+NGModalPresentation.m */,
+				2E4683D719DFF197001ECA2E /* NGModalTransitioningDelegate.h */,
+				2E4683D819DFF197001ECA2E /* NGModalTransitioningDelegate.m */,
+				2E4683DA19DFF39D001ECA2E /* NGModalAnimationController.h */,
+				2E4683DB19DFF39D001ECA2E /* NGModalAnimationController.m */,
+			);
+			path = "Custom Modal Presentation";
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */
@@ -223,10 +246,13 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				2E4683D619DFEFD3001ECA2E /* UIViewController+NGModalPresentation.m in Sources */,
 				2E4683B319DFE437001ECA2E /* ViewController.m in Sources */,
 				2E4683B019DFE437001ECA2E /* AppDelegate.m in Sources */,
+				2E4683D919DFF197001ECA2E /* NGModalTransitioningDelegate.m in Sources */,
 				2E4683D219DFE60D001ECA2E /* SampleViewController.m in Sources */,
 				2E4683AD19DFE437001ECA2E /* main.m in Sources */,
+				2E4683DC19DFF39D001ECA2E /* NGModalAnimationController.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

ModalPresentation/Custom Modal Presentation/NGModalAnimationController.h

@@ -0,0 +1,22 @@
+//
+//  NGModalAnimationController.h
+//  ModalPresentation
+//
+//  Created by Wojciech Nagrodzki on 04/10/2014.
+//
+//
+
+#import <UIKit/UIKit.h>
+
+
+typedef NS_ENUM(NSUInteger, NGModalAnimationControllerMode) {
+    NGModalAnimationControllerModePresentation,
+    NGModalAnimationControllerModeDismissal
+};
+
+
+@interface NGModalAnimationController : NSObject <UIViewControllerAnimatedTransitioning>
+
+- (instancetype)initWithMode:(NGModalAnimationControllerMode)mode;
+
+@end

ModalPresentation/Custom Modal Presentation/NGModalAnimationController.m

@@ -0,0 +1,144 @@
+//
+//  NGModalAnimationController.m
+//  ModalPresentation
+//
+//  Created by Wojciech Nagrodzki on 04/10/2014.
+//
+//
+
+#import "NGModalAnimationController.h"
+
+
+static NSTimeInterval const kTransitionDuration = 0.5;
+
+
+@interface NGModalAnimationController ()
+
+@property (assign, nonatomic, readonly) NGModalAnimationControllerMode mode;
+
+@end
+
+
+@implementation NGModalAnimationController
+
+#pragma mark - Public Instance Methods
+
+- (instancetype)initWithMode:(NGModalAnimationControllerMode)mode
+{
+    self = [super init];
+    if (self) {
+        _mode = mode;
+    }
+    return self;
+}
+
+#pragma mark - Private Instance Methods
+
+- (void)centerView:(UIView *)toView withSize:(CGSize)toViewSize inView:(UIView *)inView
+{
+    toView.translatesAutoresizingMaskIntoConstraints = NO;
+    
+    [inView addConstraint:[NSLayoutConstraint constraintWithItem:toView
+                                                       attribute:NSLayoutAttributeCenterX
+                                                       relatedBy:NSLayoutRelationEqual
+                                                          toItem:inView
+                                                       attribute:NSLayoutAttributeCenterX
+                                                      multiplier:1
+                                                        constant:0]];
+    
+    [inView addConstraint:[NSLayoutConstraint constraintWithItem:toView
+                                                       attribute:NSLayoutAttributeCenterY
+                                                       relatedBy:NSLayoutRelationEqual
+                                                          toItem:inView
+                                                       attribute:NSLayoutAttributeCenterY
+                                                      multiplier:1
+                                                        constant:0]];
+    
+    // iOS 7 applies a transform to presented view controller's view depending on device rotation
+    // Thus we need to swap width and height constraints so presented view controler can have a proper size when in landscape
+    CGFloat width = toViewSize.width;
+    CGFloat height = toViewSize.height;
+    if (NSFoundationVersionNumber <= NSFoundationVersionNumber_iOS_7_1)
+    {
+        if (CGAffineTransformEqualToTransform(toView.transform, CGAffineTransformIdentity)           == NO &&
+            CGAffineTransformEqualToTransform(toView.transform, CGAffineTransformMakeRotation(M_PI)) == NO)
+        {
+            width = toViewSize.height;
+            height = toViewSize.width;
+        }
+    }
+    
+    [inView addConstraint:[NSLayoutConstraint constraintWithItem:toView
+                                                       attribute:NSLayoutAttributeWidth
+                                                       relatedBy:NSLayoutRelationEqual
+                                                          toItem:nil
+                                                       attribute:NSLayoutAttributeNotAnAttribute
+                                                      multiplier:0
+                                                        constant:width]];
+    
+    [inView addConstraint:[NSLayoutConstraint constraintWithItem:toView
+                                                       attribute:NSLayoutAttributeHeight
+                                                       relatedBy:NSLayoutRelationEqual
+                                                          toItem:nil
+                                                       attribute:NSLayoutAttributeNotAnAttribute
+                                                      multiplier:0
+                                                        constant:height]];
+}
+
+#pragma mark - UIViewControllerAnimatedTransitioning
+
+- (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext
+{
+    return kTransitionDuration;
+}
+
+- (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext
+{
+    // get view controllers participating in the transition
+    UIViewController * fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
+    UIViewController * toViewController   = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
+    
+    // get views participating in the transition
+    UIView * containerView = [transitionContext containerView];
+    UIView * fromView;
+    UIView * toView;
+    
+    if (NSFoundationVersionNumber > NSFoundationVersionNumber_iOS_7_1)
+    {
+        fromView = [transitionContext viewForKey:UITransitionContextFromViewKey];
+        toView   = [transitionContext viewForKey:UITransitionContextToViewKey];
+    }
+    else
+    {
+        fromView = fromViewController.view;
+        toView   = toViewController.view;
+    }
+    
+    // add toView into the view hierarchy when presenting
+    if (self.mode == NGModalAnimationControllerModePresentation)
+    {
+        [containerView addSubview:toView];
+        [self centerView:toView withSize:toViewController.preferredContentSize inView:containerView];
+    }
+    
+    // find the presented view controller's view
+    UIView * presentedViewControllerView = self.mode == NGModalAnimationControllerModePresentation ? toView : fromView;
+    CGFloat initialPresentedViewAlpha    = self.mode == NGModalAnimationControllerModePresentation ? 0 : 1;
+    CGFloat finalPresentedViewAAlpha     = self.mode == NGModalAnimationControllerModePresentation ? 1 : 0;
+
+    // animate fade transition
+    presentedViewControllerView.alpha = initialPresentedViewAlpha;
+    [UIView animateWithDuration:[self transitionDuration:transitionContext]
+                          delay:0
+         usingSpringWithDamping:1
+          initialSpringVelocity:0
+                        options:UIViewAnimationOptionCurveEaseInOut
+                     animations:^{
+                         presentedViewControllerView.alpha = finalPresentedViewAAlpha;
+                     }
+                     completion:^(BOOL finished) {
+                         [transitionContext completeTransition:YES];
+                     }];
+}
+
+@end

ModalPresentation/Custom Modal Presentation/NGModalTransitioningDelegate.h

@@ -0,0 +1,13 @@
+//
+//  NGModalTransitioningDelegate.h
+//  ModalPresentation
+//
+//  Created by Wojciech Nagrodzki on 04/10/2014.
+//
+//
+
+#import <UIKit/UIKit.h>
+
+@interface NGModalTransitioningDelegate : NSObject <UIViewControllerTransitioningDelegate>
+
+@end

ModalPresentation/Custom Modal Presentation/NGModalTransitioningDelegate.m

@@ -0,0 +1,28 @@
+//
+//  NGModalTransitioningDelegate.m
+//  ModalPresentation
+//
+//  Created by Wojciech Nagrodzki on 04/10/2014.
+//
+//
+
+#import "NGModalTransitioningDelegate.h"
+#import "NGModalAnimationController.h"
+
+@implementation NGModalTransitioningDelegate
+
+#pragma mark - UIViewControllerTransitioningDelegate
+
+- (id <UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController *)presented
+                                                                   presentingController:(UIViewController *)presenting
+                                                                       sourceController:(UIViewController *)source
+{
+    return [[NGModalAnimationController alloc] initWithMode:NGModalAnimationControllerModePresentation];
+}
+
+- (id <UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController *)dismissed
+{
+    return [[NGModalAnimationController alloc] initWithMode:NGModalAnimationControllerModeDismissal];
+}
+
+@end

ModalPresentation/Custom Modal Presentation/UIViewController+NGModalPresentation.h

@@ -0,0 +1,21 @@
+//
+//  UIViewController+NGModalPresentation.h
+//  ModalPresentation
+//
+//  Created by Wojciech Nagrodzki on 04/10/2014.
+//
+//
+
+#import <UIKit/UIKit.h>
+
+@interface UIViewController (NGModalPresentation)
+
+/**
+  Presents a view controller modally.
+  @param viewControllerToPresent The view controller to display over the current view controller’s content.
+  @param flag Pass YES to animate the presentation; otherwise, pass NO.
+  @param completion The block to execute after the presentation finishes. This block has no return value and takes no parameters. You may specify nil for this parameter.
+ */
+- (void)ng_presentViewController:(UIViewController *)viewControllerToPresent animated:(BOOL)flag completion:(void (^)(void))completion;
+
+@end

ModalPresentation/Custom Modal Presentation/UIViewController+NGModalPresentation.m

@@ -0,0 +1,38 @@
+//
+//  UIViewController+NGModalPresentation.m
+//  ModalPresentation
+//
+//  Created by Wojciech Nagrodzki on 04/10/2014.
+//
+//
+
+#import "UIViewController+NGModalPresentation.h"
+#import "NGModalTransitioningDelegate.h"
+#import <objc/runtime.h>
+
+
+static void * const kTransitioningDelegateKey = (void *)&kTransitioningDelegateKey;
+
+
+@implementation UIViewController (NGModalPresentation)
+
+- (void)ng_presentViewController:(UIViewController *)viewControllerToPresent animated:(BOOL)flag completion:(void (^)(void))completion
+{
+    viewControllerToPresent.modalPresentationStyle = UIModalPresentationCustom;
+    viewControllerToPresent.transitioningDelegate = [self ng_modalTransitioningDelegate];
+    [self presentViewController:viewControllerToPresent animated:flag completion:completion];
+}
+
+- (NGModalTransitioningDelegate *)ng_modalTransitioningDelegate
+{
+    NGModalTransitioningDelegate *delegate = objc_getAssociatedObject(self, kTransitioningDelegateKey);
+    if (delegate == nil)
+    {
+        delegate = [[NGModalTransitioningDelegate alloc] init];
+        objc_setAssociatedObject(self, kTransitioningDelegateKey, delegate, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+    }
+    return delegate;
+}
+
+
+@end

ModalPresentation/ViewController.m

@@ -8,6 +8,7 @@
 
 #import "ViewController.h"
 #import "SampleViewController.h"
+#import "UIViewController+NGModalPresentation.h"
 
 
 @interface ViewController () <SampleViewControllerDelegate>
@@ -22,8 +23,9 @@
 - (IBAction)presentModalViewControllerButtonTapped:(id)sender
 {
     SampleViewController * sampleViewController = [[SampleViewController alloc] init];
+    sampleViewController.preferredContentSize = CGSizeMake(320, 640);
     sampleViewController.delegate = self;
-    [self presentViewController:sampleViewController animated:YES completion:nil];
+    [self ng_presentViewController:sampleViewController animated:YES completion:nil];
 }
 
 #pragma mark - SampleViewControllerDelegate