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Display clearColor UIViewController over UIViewController

I have a UIViewController view as a subview/modal on top of another UIViewController view, such as that the subview/modal should be transparent and whatever components is added to the subview should be visible. The problem is that I have is the subview shows black background instead to have clearColor. I'm trying to make UIView as a clearColor not black background. Does anybody know what is wrong with it? Any suggestion appreciated.

FirstViewController.m

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"SecondViewController"];

[vc setModalPresentationStyle:UIModalPresentationFullScreen];
[self presentModalViewController:vc animated:NO];  

SecondViewController.m

- (void)viewDidLoad 
{
     [super viewDidLoad];
     self.view.opaque = YES;
     self.view.backgroundColor = [UIColor clearColor];
}

RESOLVED: I fixed the issues. It is working so well for both of iPhone and iPad. Modal View Controller with no black background just clearColor/transparent. The only thing that I need to change is I replaced UIModalPresentationFullScreen to UIModalPresentationCurrentContext. How simple is that!

FirstViewController.m

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"SecondViewController"];
vc.view.backgroundColor = [UIColor clearColor];
self.modalPresentationStyle = UIModalPresentationCurrentContext;
[self presentViewController:vc animated:NO completion:nil];

NOTICE: If you are using a modalPresentationStyle property of navigationController:

FirstViewController.m

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"SecondViewController"];
vc.view.backgroundColor = [UIColor clearColor];
self.navigationController.modalPresentationStyle = UIModalPresentationCurrentContext;
[self presentViewController:vc animated:NO completion:nil];

NOTICE: The bad news is that the above solution doesn't work on iOS 7. The good news is that I fixed the issue for iOS7! I asked somebody for help and here is what he said:

When presenting a view controller modally, iOS removes the view controllers underneath it from the view hierarchy for the duration it is presented. While the view of your modally presented view controller is transparent, there is nothing underneath it except the app window, which is black. iOS 7 introduced a new modal presentation style, UIModalPresentationCustom, that causes iOS not to remove the views underneath the presented view controller. However, in order to use this modal presentation style, you must provide your own transition delegate to handle the presentation and dismiss animations. This is outlined in the 'Custom Transitions Using View Controllers' talk from WWDC 2013 https://developer.apple.com/wwdc/videos/?id=218 which also covers how to implement your own transition delegate.

You may see my solution for the above issue in iOS7: https://github.com/hightech/iOS-7-Custom-ModalViewController-Transitions

make sure you set the modalPresentationStyle of the rootViewController, otherwise it won't work
Please take a look at the comment on this answer stackoverflow.com/a/25990081/1418457, it works
This stackoverflow.com/q/27598846/1603234 make me smile, now your turn :)
I had to do self.modalPresentationStyle = UIModalPresentationCurrentContext; with the presented view controller to make it work, not with the presenting one.
Check Brody's answer below. modalViewController.modalPresentationStyle = UIModalPresentationOverCurrentContext; will solve the issue,

B
Brody Robertson

iOS8+

In iOS8+ you can now use the new modalPresentationStyle UIModalPresentationOverCurrentContext to present a view controller with a transparent background:

MyModalViewController *modalViewController = [[MyModalViewController alloc] init];
modalViewController.modalPresentationStyle = UIModalPresentationOverCurrentContext;           
[self presentViewController:modalViewController animated:YES completion:nil];    

Should be the accepted answer. Previously accepted answer is still valid for legacy reasons, but this is the recommended method.
If you're developing for ios 8 only, go with this answer! It works
This is good, but shouldn't the last line be [self presentViewController:modalViewController animated:YES completion:nil];? (instead of targetController)?
In order to work this for me I added modalViewController.view.backgroundColor = UIColor.clearColor() thanks for the solution
can anyone provide me the code for pushviewcontroller too (I mean for navigation controller ) .
h
hightech

RESOLVED: I fixed the issues. It is working so well for both of iPhone and iPad. Modal View Controller with no black background just clearColor/transparent. The only thing that I need to change is I replaced UIModalPresentationFullScreen to UIModalPresentationCurrentContext. How simple is that!

FirstViewController.m

    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
    UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"SecondViewController"];
    vc.view.backgroundColor = [UIColor clearColor];
    self.modalPresentationStyle = UIModalPresentationCurrentContext;
    [self presentViewController:vc animated:NO completion:nil];

NOTICE: If you are using a modalPresentationStyle property of navigationController:

FirstViewController.m

    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
    UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"SecondViewController"];
    vc.view.backgroundColor = [UIColor clearColor];
    self.navigationController.modalPresentationStyle = UIModalPresentationCurrentContext;
    [self presentViewController:vc animated:NO completion:nil];

NOTICE: The bad news is that the above solution doesn't work on iOS 7. The good news is that I fixed the issue for iOS7! I asked somebody for help and here is what he said:

When presenting a view controller modally, iOS removes the view controllers underneath it from the view hierarchy for the duration it is presented. While the view of your modally presented view controller is transparent, there is nothing underneath it except the app window, which is black. iOS 7 introduced a new modal presentation style, UIModalPresentationCustom, that causes iOS not to remove the views underneath the presented view controller. However, in order to use this modal presentation style, you must provide your own transition delegate to handle the presentation and dismiss animations. This is outlined in the 'Custom Transitions Using View Controllers' talk from WWDC 2013 https://developer.apple.com/wwdc/videos/?id=218 which also covers how to implement your own transition delegate.

You may see my solution for the above issue in iOS7: https://github.com/hightech/iOS-7-Custom-ModalViewController-Transitions


self.modalPresentationStyle = UIModalPresentationCurrentContext; did it.
btw.. I have observed that because of self.modalPresentationStyle = UIModalPresentationCurrentContext; it is not presenting modalViewController with animation .. any ideas?
@Miraaj Then setting modalPresentationStyle back to UIModalPresentationFullScreen before showing UIViewController should work self.modalPresentationStyle = UIModalPresentationFullScreen; [self performSegueWithIdentifier:@"CustomSegue" sender:self];
Running this in iOS 6 and 7, the new view controller is clear while animating the presentation, but once it is in place the background turns black. It turns clear again when animating the dismissal. Has anyone else had this issue?
@pkamb I updated the solution for iOS 7. stackoverflow.com/a/11252969/1344459 I hope that helps you.
m
mfaani

So for purely visual thinkers and storyboard fans, you can do:

1. Presenting View Controller

https://i.stack.imgur.com/ZS2ODl.png

2. Presented View Controller

https://i.stack.imgur.com/4PNitl.png


This should be the accepted answer. This is all you have to do for this to work, then set the background color of the view on the modal controller to clear.
Agreed, storyboard options overwrite the code in this case.
This answer is so sweet, I now have diabetes.
F
FreeGor

Swift 3 & iOS10 solution :

//create view controller
let vc = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "RoadTripPreviewViewController")
//remove black screen in background
vc.modalPresentationStyle = .overCurrentContext
//add clear color background
vc.view.backgroundColor = UIColor.clear
//present modal
self.present(vc, animated: true, completion: nil)

S
SmileBot

This is from xCode 7 beta 4 using a control drag segue. Simply set the background of your destination to clear, and set the segue properties in IB as this (nb. Presentation can also be "Over Full Screen"):

https://i.stack.imgur.com/ll10s.png


THANK YOU. i did your segue fix + the ViewControllers answer by @pasevin and it worked!!
This answered my question. Thank you very much. Have an up vote :D
3
3vangelos

I found the easiest way to get it to work on iOS7 and iOS8 is to add set the presentationStyle to UIModalPresentationOverCurrentContext on the modallyPresentedVC (ViewController which you want to present modally) because of iOS8:

[modallyPresentedVC setModalPresentationStyle:UIModalPresentationOverCurrentContext];
[modallyPresentedVC.navigationController setModalPresentationStyle:UIModalPresentationOverCurrentContext];

and UIModalPresentationCurrentContext on presentingVC (the controller which presents the modallyPresented) because of iOS7:

[presentingVC setModalPresentationStyle:UIModalPresentationCurrentContext];
[presentingVC.navigationController setModalPresentationStyle:UIModalPresentationCurrentContext];

Because things are handled differently on iOS7 and iOS8. Of course you don't have to set the navigationController properties if you are not using one. Hope that helps.


saved my bacon! Thanks
M
Mojtaba Yeganeh

Swift2 version :

let vc = self.storyboard!.instantiateViewControllerWithIdentifier("YourViewController") as! YourViewController
vc.view.backgroundColor = UIColor.clearColor()
vc.modalPresentationStyle = UIModalPresentationStyle.OverFullScreen // orOverCurrentContext to place under navigation
self.presentViewController(vc, animated: true, completion: nil)

e
educaPix

Another way (no need to create custom transition and works on iOS 7)

Using Storyboard:

Create the Child View Controller with freedom size, set view width to 500x500 (for example) and add the next method:

- (void)viewWillLayoutSubviews{
    [super viewWillLayoutSubviews];
    self.view.superview.bounds = CGRectMake(0, 0, 500, 500);
    self.view.superview.backgroundColor = [UIColor clearColor];
}

Then create a Modal segue with Form Sheet and test it.


You are amazing!!! this actually works!!! (setting the "freedom" size in IB doesn't affect anithing cose it is a simulated metric, but anyway, it works!!!) and it is so simple!!!
M
Max Gribov

iOS 7 solution with custom segue:

CustomSegue.h
#import <UIKit/UIKit.h>

    @interface CustomSegue : UIStoryboardSegue <UIViewControllerTransitioningDelegate, UIViewControllerAnimatedTransitioning>

    @end



CustomSegue.m
#import "CustomSegue.h"

@implementation CustomSegue

-(void)perform {

    UIViewController* destViewController = (UIViewController*)[self destinationViewController];
    destViewController.view.backgroundColor = [UIColor clearColor];
    [destViewController setTransitioningDelegate:self];
    destViewController.modalPresentationStyle = UIModalPresentationCustom;
    [[self sourceViewController] presentViewController:[self destinationViewController] animated:YES completion:nil];
}


//===================================================================
// - UIViewControllerAnimatedTransitioning
//===================================================================

- (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext {
    return 0.25f;
}

- (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext {

    UIView *inView = [transitionContext containerView];
    UIViewController* toVC = (UIViewController*)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    UIViewController* fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];

    [inView addSubview:toVC.view];

    CGRect screenRect = [[UIScreen mainScreen] bounds];
    [toVC.view setFrame:CGRectMake(0, screenRect.size.height, fromVC.view.frame.size.width, fromVC.view.frame.size.height)];

    [UIView animateWithDuration:0.25f
                     animations:^{

                         [toVC.view setFrame:CGRectMake(0, 0, fromVC.view.frame.size.width, fromVC.view.frame.size.height)];
                     }
                     completion:^(BOOL finished) {
                         [transitionContext completeTransition:YES];
                     }];
}


//===================================================================
// - UIViewControllerTransitioningDelegate
//===================================================================

- (id <UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source {

    return self;
}

- (id <UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController *)dismissed {
    //I will fix it later.
    //    AnimatedTransitioning *controller = [[AnimatedTransitioning alloc]init];
    //    controller.isPresenting = NO;
    //    return controller;
    return nil;
}

- (id <UIViewControllerInteractiveTransitioning>)interactionControllerForPresentation:(id <UIViewControllerAnimatedTransitioning>)animator {
    return nil;
}

- (id <UIViewControllerInteractiveTransitioning>)interactionControllerForDismissal:(id <UIViewControllerAnimatedTransitioning>)animator {
    return nil;
}

@end

Solution based on hightech code.


When I dismiss the by [self dismissViewControllerAnimated:YES completion:NULL]; I get an exception ??
Yes for this code. Or you have to implement animationControllerForDismissedController method for animation begin work.
M
Manab Kumar Mal

For Me this Works:

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main_iPhone" bundle:nil];
    UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"MMPushNotificationViewController"];

    vc.view.backgroundColor = [UIColor clearColor];
    self.modalPresentationStyle = UIModalPresentationCurrentContext;
#ifdef __IPHONE_8_0
    if(IS_OS_8_OR_LATER)
    {
        self.providesPresentationContextTransitionStyle = YES;
        self.definesPresentationContext = YES;
        [vc setModalPresentationStyle:UIModalPresentationOverCurrentContext];
    }
#endif


    [self presentViewController:vc animated:NO completion:nil];

MMPushNotificationViewController is the Transparent View controller and also I have made the MMPushNotificationViewController's view color as clearcolor. Now All that I have Done and made my Transparentviewcontroller.


C
Community

For iOS7

There is now a way to achieve this using the iOS7 custom transitions, this way :

MyController * controller = [MyController new];
[controller setTransitioningDelegate:self.transitionController];
controller.modalPresentationStyle = UIModalPresentationCustom;
[self controller animated:YES completion:nil];

To create your custom transition, you need 2 things :

A TransitionDelegate object (implementing )

An "AnimatedTransitioning" object (implementing )

You can find more informations on custom transitions in this tutorial.


Any specific reasons why you have added mainviewcontroller and second view controller class in animator class? why didn't you directly use UIViewController *toVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey]; UIViewController *fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
It's not my tutorial so I don't know the ins and outs about this. Your point seems valid though.
h
hoppus

Works Great on iOS7 and iOS8

UIViewController* vc=[[UIViewController alloc]initWithNibName:@"VC" bundle:nil];

vc.view.alpha=0.7;
[vc setModalPresentationStyle:UIModalPresentationOverCurrentContext];

self.navigationController.modalPresentationStyle = UIModalPresentationCurrentContext;

[self presentViewController:vc animated:NO completion:nil];

A duplicate of the second best answer.
R
Rajat

You also can 're-add' the window to the view.

OneViewController *vc = [[OneViewController alloc] init];
if ([self respondsToSelector:@selector(presentViewController:animated:completion:)]) {
    [self presentViewController:vc animated:YES completion:nil];
} else {
    [self presentModalViewController:vc animated:YES];
}

[[[UIApplication sharedApplication] keyWindow] insertSubview:self.view atIndex:0];

And in this way, presenting can be animated.


D
David H.

For iOS 7 and only by using Interface Builder it can be accomplished by setting the Presentation to "Over Current Context" on all the view controllers involved in the modal presentation. Even for navigation controllers.

For instance, set it on all these view controllers:

NavController -> RootViewController -> ModalViewController

https://i.stack.imgur.com/N1wv1.png


W
WendiKidd

I haven't played around with Storyboard/Interface builder much, but what pops out at me is that you're telling the view to be clear colored (ie. 100% alpha/see-through) and also telling it to be opaque (0% alpha--completely solid). These two things don't seem to mesh. I'd comment out the self.view.opaque = YES; line and see if it works then ;)

Ah, something else I just thought of--its entirely possible that your view controller DOES have the alpha background, but of course the alpha will be showing through to the color of the base window or root view controller of the program, which is by default black. The very base layer of your entire app can't have a transparent background--transparent to what? What's behind it? There has to be something to see THROUGH the transparency. Does that make sense?


I tried to comment out the self.view.opaque = YES; line and it doesn't working. :-(
Did you read the second part of my answer? You might not be able to do what you want, depending on your setup. What are you placing behind the clearColor VC? Maybe we can sort this out ^^
V
Venkateswarlu.NP

Just use "self.modalPresentationStyle = UIModalPresentationCurrentContext;", in presenting view

Will work fine :)


This is just repeating what the existing answers have already said.

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