i like to create a second starting screen in my app.
My Idea is to use the default.png and load an UIView with an fullscreen UIImageView inside.
In viewDidLoad i thought about placing a sleep option and after this load the real app screen.
But also when my function is called in viewDidLoad, nothing happens.
Seems my superview is empty...
Here is a piece of code:
if (self._pdfview == nil)
{
pdfview *videc = [[pdfview alloc]
initWithNibName:#"pdfview" bundle:nil];
self._pdfview = videc;
[pdfview release];
}
// get the view that's currently showing
UIView *currentView = self.view;
// get the the underlying UIWindow, or the view containing the current view
UIView *theWindow = [currentView superview];
theWindow is empty after this line so that might be the reason why the other view is not loaded.
So my question, how do i create a second starting screen ?
Or three starting screens, like in games when i like to mention another company.
If I understand correctly, your point is that when your function above is executed from viewDidLoad of some controller, theWindow is nil, so your new view (startscreen) is not added to it.
A few observations:
if theWindow is nil, then self.view is the topmost UIView; you can try and replace it, or simply add your view to it:
UIView *currentView = self.view;
// get the the underlying UIWindow, or the view containing the current view
UIView *theWindow = [currentView superview];
UIView *newView = _pdfview.view;
if (theWindow) {
[currentView removeFromSuperview];
[theWindow addSubview:newView];
} else {
self.view = newView; //-- or: [self.view addSubview:newView];
}
if you want to get the UIWindow of your app (which seems what you are trying to do), you can do:
[UIApplication sharedApplication].keyWindow;
and from there you can either set the rootViewController (from iOS 4.0)
[UIApplication sharedApplication].keyWindow.rootViewController = ...;
or add newView as a subview to it:
[[UIApplication sharedApplication].keyWindow addSubview:newView];
in the second case, you should possibly remove all subviews previously added to the UIWindow. (Iterate on keyWindow.subviews and call removeFromSuperview).
OLD ANSWER:
I think that you should try and add your pdfview as a subview to the current view:
[currentView addSubview:videc];
or to what you call theWindow:
[theWindow addSubview:pvidec];
and, please, move the release statement after the `addSubview, otherwise the view will be deallocated immediately.
Related
I need to add a subview to left part of UIViewController, which shows the user that there is something near the left part of screen, when masterview is hidden(in portrait orientation). And this view must move with left part of UISplitView. Something like the view with arrow in these two images. (Sorry for the russian interface)
http://s2.uploads.ru/8EHJI.png
http://s2.uploads.ru/NhEam.png
But my problem is that when I try to add such a view, it clips to bounds of masterview and is not visible when masterview is hidden. I think, I'm doing it wrong and there is an easy way to do this.
Update: I've tried to make some hack like:
-(void) clipToBoundsRecursive:(UIView *)someView
{
NSLog(#"%#", someView);
someView.clipsToBounds = NO;
for (UIView *v in someView.subviews)
{
[self clipToBoundsRecursive:v];
}
}
and send it to view of splitviewcontroller.
UISplitViewController *splitViewController = (UISplitViewController *)self.window.rootViewController;
[self clipToBoundsRecursive:splitViewController.view];
It takes effect at first time (subviews outside the masterview's bounds shows, but after first show/hide animation they disappears and don't appear even if I call this method again)
You can add the view directly to the window's view, though you will have to manually manage its position depending on when the device rotates. Views added to the window.view will appear above the rootViewController.view.
I have described here a simple Logic for you: (how to add a UIView in Window and call it from your master or detail view )
Create UIView in #import "AppDelegate.h" ,
- (void) CreateViewInWindow
{
UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 780)];// set as u wish
myView.backgroundColor = [UIColor redColor];
// I have added myView to the Window with a specific animation , your can give animation as you like. :)
[UIView transitionWithView:self.window duration:0.5
options:UIViewAnimationOptionTransitionCrossDissolve // change to whatever animation you like
animations:^ { [self.window addSubview:myView]; }
completion:nil];
}
Here create a simple UIButton in the DetailViewController.m file (You can put the code in either of the files, DetailViewController.m OR MasterViewController.m)
UIButton *btnShowView = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[btnShowView addTarget:self action:#selector(btnShowViewTapped:) forControlEvents:UIControlEventTouchUpInside];
btnShowView.frame = CGRectMake(20, 30, 174, 35);
//[btnLoginInner setBackgroundImage:[UIImage imageNamed:#"LoginBut.png"] forState:UIControlStateNormal];
[self.view addSubview:btnShowView];
In button tapped method, write code for calling UIView from AppDelegate, and also don't forget to add #import "AppDelegate.h" in DetailViewController.m,
-(void)btnShowViewTapped:(UIButton *) Sender
{
AppDelegate *del = (AppDelegate *)[[UIApplication sharedApplication] delegate];
[del performSelector:#selector(CreateViewInWindow) withObject:nil afterDelay:0];
}
Above code is a simple logic for your problem, It might be helpful for you.
Sounds to me like your app could benefit from PKRevealController.
Try with deselecting auto layout option in identity and type pan if you are using nib otherwise set autoresizing mask to view that currently clipping. I believe it will solve the issue
I want to instantiate a viewController and place it behind the currently shown view. Then move the original view's fram to reveal the view behind it.
I CANNOT create the bottom view first and add the top view on top. I will be creating multiple bottom views and memory can't handle the whole stack at once.
Problems I've already encountered.
Adding a subView and sending it to the back means moving the original view's frame move's the entire view, not revealing the new one.
Instantiating the new view and calling presentViewController deallocs the original view (if I add it modally)
Can anyone help? Or lead me in a direction?
Is it fair to say you're going for a transition from vc1 to vc2 where what you want is the appearance that vc2 was underneath vc1 and vc1 slid out of the way to reveal it?
If so, then that's doable without doing anything unusual or dangerous from the sdk perspective. The trick is to do the normal instantiate and present steps, but in vc1, before presenting vc2, hand it a UIImage that looks like vc1. Vc2 covers itself with that image before it appears, then slides the image out of the way to reveal itself.
Here are the steps:
1) On vc1, implement the method in this post. It captures an image of the view.
2) There's some action that makes you want to present vc2, do it like this...
- (void)presentVc2:(id)sender {
UIImage *image = [self makeImage]; // it was called makeImage in the other post, consider a better name
MyViewController2 *vc2 = [[MyViewController2 alloc] initWithNibName:#"MyViewController2" bundle:nil];
vc2.presentationImage = image; // more on this later
// this line will vary depending on if you're using a container vc, but the key is
// to present vc2 with NO animation
[self presentViewController:vc2 animated:NO completion:^{}];
}
3) Create a UIImage property on MyViewController2 called presentationImage and make it's setter public. Then in MyViewController2 ...
// before we appear, cover with the last vc's image
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
UIImageView *imageView = [[UIImageView alloc] initWithImage:self.presentationImage];
imageView.frame = self.view.bounds;
imageView.tag = 128;
[self.view addSubview:imageView];
}
// after we appear, animate the removal of that image
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
UIImageView *imageView = (UIImageView *)[self.view viewWithTag:128];
[UIView animateWithDuration:0.5 animations:^{
imageView.frame = CGRectOffset(imageView.frame, -self.frame.size.width, 0);
}];
}
You could simply put the top view's contents into a new UIView whose frame is equal to your view controller's view's frame. Then stick your bottom views below the container view. Moving the container view, then, will move all of its contents but leave the bottom views in tact.
Is it possible with a standard UINavigationController-rooted app, to have a single ADBannerView visible at the bottom of the screen, below the view hierarchy? That is, without modifying each view-controller/view that can be pushed to the root UINavigationController, can I have a global ADBannerView be visible?
I'm not sure how to set this up, either in IB or in code. Help?
I see similar questions with vague answers. I'm looking for a concrete example.
EDIT: The better way to do this in iOS5+ is likely to use view controller containment. That is, make a root controller that contains your ad and application controller (nav, tab, etc.).
I figured out a way to do this. Here is what I did:
For my first attempt I created a new view controller called AdBannerController. For its view I created a full-screen view and two subviews. The first subview (contentView) is for regular content, the second is the AdBannerView. I used an instance of this view controller as the view controller associated with the app window ( [window addSubview: adBannerController.view] ). Then I added my UINavigationController.view as a subview of adBannerController.view: [adBannerController.contentView addSubview: navigationController.view].
This mostly worked except that viewcontrollers pushed to the UINavigationController never got their will/did-load/unload methods called. Shucks. I read in a few places that this is a symptom of the UINavigationController view not being a direct descendant of the app window.
For my second attempt I took the same AdBannerController and derived it from UINavigationController. This time, I did the following in loadView:
- (void)loadView
{
[super loadView];
_contentView = [self.view retain];
self.view = [[[UIView alloc] initWithFrame: _contentView.frame] autorelease];
[self.view addSubview: _contentView];
_adView = [[ADBannerView alloc] initWithFrame: CGRectMake(0, _contentView.bounds.size.height, 320, 50)];
_adView.currentContentSizeIdentifier = ADBannerContentSizeIdentifier320x50;
_adView.delegate = self;
[self.view addSubview: _adView];
/* for visual debugging of view layout
[[_mainView layer] setCornerRadius: 6.0];
[[_mainView layer] setMasksToBounds: YES];
[[_mainView layer] setBorderWidth: 1.5];
[[_mainView layer] setBorderColor: [[UIColor grayColor] CGColor]];
*/
}
Notice what happens - I let the superclass UINavigationController construct its regular "content" view, but I swap it out and replace it with my own view which is a container for both the content and ad views.
This works pretty well. I'm also using three20 and there were a few things required to make this work with that setup, but not too bad.
I hope this helps someone!
In Apple's dev sample code the iAdSuite project contents projects that have this done for you. Highly recommended.
In my root view controller (w/ ADBannerViewDelegate) I setup my banner by adding it to the nav controller view, which keeps it on top at all times:
banner = [[ADBannerView alloc] init];
banner.delegate = self;
banner.frame = CGRectMake(0.0, 430.0, banner.frame.size.width, banner.frame.size.height);
[self.navigationController.view addSubview:banner];
Note you will have to comment out layoutAnimated in delegate method bannerViewDidLoadAd as it will try to move the ad view up:
- (void)bannerViewDidLoadAd:(ADBannerView *)banner
{
//[self layoutAnimated:YES];
}
I adapted the approach suggested in the iAdSuite given here
http://developer.apple.com/library/ios/#samplecode/iAdSuite/Introduction/Intro.html
I downloaded the code and focused on the 'tab' example. I copied over the BannerViewController.h/.m as is into my project.
I created all my views in the usual way with the storyboard approach. However, in my AppDelegate class I then accessed the already built tab bar - containing all the storyboard built viewControllers.
The AppDelegate class implements the TabBarControllerDelegate protocol:
#interfaceAppDelegate : UIResponder <UITabBarControllerDelegate, UIApplicationDelegate>
The AppDelegate implementation didFinishLaunchingWithOptions method grabs the pre-built tabBar, setting its delegate to self (e.g. the AppDelegate class).
-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:
// ----------------------------------------------------------
// Set the TabBarController delegate to be 'self'
// ----------------------------------------------------------
_tabBarController = (UITabBarController*)self.window.rootViewController;
// tabController.selectedIndex = [defaults integerForKey:kOptionLastTabSelectedKey];
_tabBarController.delegate = self;
// update tab bar per iAdSuite approach
[self updateiAd];
I then built a new set of controllers per the iAdSuite approach and reset the tab bar with these new tab bar items.
-(void)updateiAd {
NSArray* viewControllers = [_tabBarController viewControllers];
NSMutableArray*newViewControllers = [[NSMutableArray alloc] init];
BannerViewController*bvc=NULL;
for(UIViewController * vc in viewControllers) {
bvc = [[BannerViewController alloc] initWithContentViewController:vc];
[newViewControllers addObject:bvc];
}
// set the new view controllers, replacing the original set
[_tabBarController setViewControllers:newViewControllers];
}
This approach puts the same 'ad' at the bottom of each view, exactly as needed. I also had to set the view title in the viewDidLoad method of each custom viewController (somehow, setting it on the bar item didn't seem to work not did setting the image; the later may reflect an issue with my images however).
My original configuration was
TabViewController
NavController1 NavController2 NavController3 ...
| | |
CustomViewController1 CustomViewController2 CustomViewController3
My final configuration is now
TabViewController
NavController1 NavController2 NavController3 ...
| | |
iAdView1 iAdView2 iAdView3
| | |
CustomViewController1 CustomViewController2 CustomViewController3
In terms of view lifecycle, I should add that only the NavControllers are in existence at the time the updateiAd method is called.
The individual CustomViewControllers1/2/3/etc get created after the call completes.
In a view based app, I display a view and once the user is finished with that view, Done is clicked and the view is removed. However, that does not dealloc the view, which is what I want to do. What is the proper way to dealloc this type of view?
Currently, I'm nil'ing out the second view before it is called. That seems to work and the second view is reinitialized. However, isn't it more appropriate for the second view to destroy itself (nil itself after removeFromSuperview)?
In first view:
//show next view
aView = nil;
if(aView == nil)
{
aView = [[AView alloc] initWithNibName:#"aView" bundle:nil];
}
[self.view addSubview: aView.view];
Click Done in aView
[self.view removeFromSuperview];
The method removeFromSuperview will automatically release "aView.view", so you shouldn't release aView in the first view controller. I think you've declared AView *aView in head file, but you don't need to. You may declare the aView as a local variable like this:
// go to second view
SecViewController *sec = [[SecViewController alloc] initWithNibName:#"SecView" bundle:nil];
[self.view addSubview:sec.view];
// go back
[self.view removeFromSuperview];
Immediately after
[self.view addSubview: aView.view];
You should add:
[aView release];
Your subview has been retained by your view controller's view so can be release.
If you previously set your viewController to first responder status (like to respond to motion events) the responder chain will retain the controller. You must resign the first responder to destroy the controller completely.
[self resignFirstResponder];
[self.view removeFromSuperview];
both of the above answers are correct theory for how you should memory manage in objective c.
as per the dev documentation:
http://developer.apple.com/iPhone/library/documentation/UIKit/Reference/UIView_Class/UIView/UIView.html#//apple_ref/occ/instm/UIView/removeFromSuperview
callling removeFromSuperview will actually call release FOR you, so you are okay, I think.
I'm trying to create a transparent modal View on top of my navigation controller. Does anyone know if this is possible?
A modal view will cover the view it is pushed on top of as well as the navigation bar for your navigation controller. However, if you use the -presentModalViewController:animated: approach, then once the animation finishes the view just covered will actually disappear, which makes any transparency of your modal view pointless. (You can verify this by implementing the -viewWillDisappear: and -viewDidDisappear: methods in your root view controller).
You can add the modal view directly to the view hierarchy like so:
UIView *modalView =
[[[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
modalView.opaque = NO;
modalView.backgroundColor =
[[UIColor blackColor] colorWithAlphaComponent:0.5f];
UILabel *label = [[[UILabel alloc] init] autorelease];
label.text = #"Modal View";
label.textColor = [UIColor whiteColor];
label.backgroundColor = [UIColor clearColor];
label.opaque = NO;
[label sizeToFit];
[label setCenter:CGPointMake(modalView.frame.size.width / 2,
modalView.frame.size.height / 2)];
[modalView addSubview:label];
[self.view addSubview:modalView];
Adding the modalView as a subview to the root view like this will not actually cover the navigation bar, but it will cover the entire view below it. I tried playing around with the origin of the frame used to init the modalView, but negative values cause it to not display. The best method that I found to cover the entire screen besides the status bar is to add the modalView as a subview of the window itself:
TransparentModalViewAppDelegate *delegate = (TransparentModalViewAppDelegate *)[UIApplication sharedApplication].delegate;
[delegate.window addSubview:modalView];
The easiest way is to use modalPresentationStyle property of navigationController (but you'll have to make animation by yourself):
self.navigationController.modalPresentationStyle = UIModalPresentationCurrentContext;
[self presentModalViewController:modalViewController animated:NO];
modalViewController.view.alpha = 0;
[UIView animateWithDuration:0.5 animations:^{
modalViewController.view.alpha = 1;
}];
I accomplish this most easily by setting up an "OverlayViewController" that sits above all other subviews of my window or root view. Set this up in your app delegate or root view controller, and make OverlayViewController a singleton so that it can be accessed from anywhere in your code or view controller hierarchy. You can then call methods to show modal views, show activity indicators, etc, whenever you need to, and they can potentially cover any tab bars or navigation controllers.
Sample code for root view controller:
- (void)viewDidLoad {
OverlayViewController *o = [OverlayViewController sharedOverlayViewController];
[self.view addSubview:o.view];
}
Sample code you might use to display your modal view:
[[OverlayViewController sharedOverlayViewController] presentModalViewController:myModalViewController animated:YES];
I haven't actually used -presentModalViewController:animated: with my OverlayViewController but I expect this would work just fine.
See also: What does your Objective-C singleton look like?
I had this same problem and in order to The solution is to add the modal view with addSubview: and animate the change in the view hierarchy with UIView’s animateWithDuration:delay:options:animations:completion:
I added a property and 2 methods to a subclass of UIViewController (FRRViewController) that includes other functionalities. I will be publishing the whole stuff on gitHub soon, but until then you can see the relevant code below. For more info, you can check my blog: How to display a transparent modal view controller.
#pragma mark - Transparent Modal View
-(void) presentTransparentModalViewController: (UIViewController *) aViewController
animated: (BOOL) isAnimated
withAlpha: (CGFloat) anAlpha{
self.transparentModalViewController = aViewController;
UIView *view = aViewController.view;
view.opaque = NO;
view.alpha = anAlpha;
[view.subviews enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
UIView *each = obj;
each.opaque = NO;
each.alpha = anAlpha;
}];
if (isAnimated) {
//Animated
CGRect mainrect = [[UIScreen mainScreen] bounds];
CGRect newRect = CGRectMake(0, mainrect.size.height, mainrect.size.width, mainrect.size.height);
[self.view addSubview:view];
view.frame = newRect;
[UIView animateWithDuration:0.8
animations:^{
view.frame = mainrect;
} completion:^(BOOL finished) {
//nop
}];
}else{
view.frame = [[UIScreen mainScreen] bounds];
[self.view addSubview:view];
}
}
-(void) dismissTransparentModalViewControllerAnimated:(BOOL) animated{
if (animated) {
CGRect mainrect = [[UIScreen mainScreen] bounds];
CGRect newRect = CGRectMake(0, mainrect.size.height, mainrect.size.width, mainrect.size.height);
[UIView animateWithDuration:0.8
animations:^{
self.transparentModalViewController.view.frame = newRect;
} completion:^(BOOL finished) {
[self.transparentModalViewController.view removeFromSuperview];
self.transparentModalViewController = nil;
}];
}
}
Here's what I did to solve the problem - Google the details but this approach worked very well for me:
Take a screenshot of the underlying view. https://devforums.apple.com/message/266836 - this leads to a ready-made method that returns a UIView for the current screen.
Hand the screenshot to the modal view (I used a property)
Present the modal view
In the modal view controller's viewDidAppear, set the image as UIImageView at index 0. Adjust the vertical position of the image by the height of the status bar.
In the modal view controller's viewWillDisappear, remove the image again
The effect is:
The view animates in as any modal view does - the semi transparent parts of the modal view glide over the existing view
As soon as the animation stops, the background is set to the screenshot - this makes it appear as if the old view is still underneath even though it isn't.
As soon as the modal view's disappear animation starts, the image is removed. The OS meanwhile shows the old navigation view so the modal view transparently glides away and out of sight as you'd expect.
I tried animating in my own overlay view but it didn't work very well. I got a crash with no indication as to what has crashed. Rather than chase this down I did the bg view & Works really well.
Code in the modal view - I think you can figure out the rest, namely setting the property modalView.bgImage...
- (void)viewDidAppear:(BOOL)animated {
// background
// Get status bar frame dimensions
CGRect statusBarRect = [[UIApplication sharedApplication] statusBarFrame];
UIImageView *imageView = [[UIImageView alloc] initWithImage:self.bgImage];
imageView.tag = 5;
imageView.center = CGPointMake(imageView.center.x, imageView.center.y - statusBarRect.size.height);
[self.view insertSubview:imageView atIndex:0];
}
- (void)viewWillDisappear:(BOOL)animated {
[[self.view viewWithTag:5] removeFromSuperview];
}
self.modalPresentationStyle = UIModalPresentationCurrentContext;
[self presentModalViewController:newview animated:YES];
and make sure you setup the modal view background to be transparent,
self.view.background = .... alpha:0.x;
if you set modalPresentationStyle for the modal view controller to:
viewController.modalPresentationStyle = 17;
The view in the background is not removed. (TWTweetComposeViewController use it).
I did not try to pass App Store review with this code though
This post about displaying a semi-transparent "Loading..." view might give a few pointers on how to proceed.
Yeah, you have to add the view manually, and if you want to slide in from the bottom or whatever you have to do the animation yourself too.
I wrote a class to do this, and a semi-modal datepicker using that class as an example.
You can find documentation in this blog post, the code is on github
I've been researching this same issue for the past week. I tried all the various answers and examples found in Google and here on StackOverflow. None of them worked that well.
Being new to iOS programming, I wasn't aware of something called UIActionSheet. So if you're trying to accomplish this in order to show a modal overlay of buttons (such as a modal asking someone how they want to share something), just use UIActionSheet.
Here is a webpage that shows an example of how to do this.
I got this idea from https://gist.github.com/1279713
Prepare:
In the modal view xib (or scene using storyboard), I setup the full-screen background UIImageView (hook it with the .h file and give it a property "backgroundImageView") with 0.3 alpha. And I set the view (UIView) background color as plain black.
Idea:
Then in "viewDidLoad" of the modal view controller I capture the screenshot from the original status and set that image to the background UIImageView. Set the initial Y point to -480 and let it slide to Y point 0 using 0.4-second duration with EaseInOut animation option. When we dismiss the view controller, just do the reverse thing.
Code for the Modal View Controller Class
.h file:
#property (weak, nonatomic) IBOutlet UIImageView *backgroundImageView;
- (void) backgroundInitialize;
- (void) backgroundAnimateIn;
- (void) backgroundAnimateOut;
.m file:
- (void) backgroundInitialize{
UIGraphicsBeginImageContextWithOptions(((UIViewController *)delegate).view.window.frame.size, YES, 0.0);
[((UIViewController *)delegate).view.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage * screenshot = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
backgroundImageView.image=screenshot;
}
- (void) backgroundAnimateIn{
CGRect backgroundImageViewRect = backgroundImageView.frame;
CGRect backgroundImageViewRectTemp = backgroundImageViewRect;
backgroundImageViewRectTemp.origin.y=-480;
backgroundImageView.frame=backgroundImageViewRectTemp;
[UIView animateWithDuration:0.4 delay:0.0 options:UIViewAnimationCurveEaseInOut animations:^{
backgroundImageView.frame=backgroundImageViewRect;
} completion:^(BOOL finished) {
}];
}
- (void) backgroundAnimateOut{
CGRect backgroundImageViewRect = backgroundImageView.frame;
backgroundImageViewRect.origin.y-=480;
[UIView animateWithDuration:0.4 delay:0.0 options:UIViewAnimationCurveEaseInOut animations:^{
backgroundImageView.frame=backgroundImageViewRect;
} completion:^(BOOL finished) {
}];
}
In viewDidLoad, simply call:
[self backgroundInitialize];
[self backgroundAnimateIn];
In anywhere we dismiss the modal view controller, we call:
[self backgroundAnimateOut];
Please note that this will ALWAYS animate the background image. So if this modal view controller transition style (or the segue transition style) is not set to "Cover Vertical", you may not need to call the animation methods.
I finally accomplished this, for a navigation or tab bar interface, by combining an overlay view controller (see: pix0r's answer) that's hidden / un-hidden before hiding or showing a view controller based on this very good blog post.
Concerning the view controller, the tip is to make its background view the clearColor, then the semi-transparent overlay view is visible and whatever views are added as subviews in the view controller are in front and most importantly opaque.
I've created open soruce library MZFormSheetController to present modal form sheet on additional UIWindow. You can use it to present transparency modal view controller, even adjust the size of the presented view controller.
For iOS 8+ you can use UIModalPresentationOverCurrentContext presentation style for presented view controller to easy achieve desired behavior.
UIViewController *viewController = [[UIViewController alloc] init];
viewController.view.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.9f];
viewController.modalPresentationStyle = UIModalPresentationOverCurrentContext;
[self presentViewController:viewController animated:YES completion:nil];
If you also need to support iOS 7 - check this thread.
You can achieve transparent/semi-transparent modal view effect by overlaying a transparent/semi-transparent button on both the view and the navigation bar.
You can access the navigation bar through the navigationBar property of the UINavigationController.
I found that UIButton unlike UILabel will trap mouse events - hence giving the correct modal behavior.
I just found a workaround for that. Just create a 1X1 of UIViewController and add it to your parent view controller. And show the transparent modal view controller in that UIViewController.
on viewDidLoad;
self.dummyViewController = [[UIViewController alloc] init];
[self.dummyViewController.view setFrame:CGRectMake(0, 0, 1, 1)];
[self.view addSubView:self.dummyViewController.view];
when you need to open a transparentViewController;
[self.dummyViewController presentModalViewController:yourTransparentModalViewController animated:true];
If you need a screen like the attached one, the below code may help you.
The code:
MyViewController * myViewController = [[MyViewController alloc] initWithNibName:nibName bundle:nil];
UINavigationController * myNavigationController = [[UINavigationController alloc] initWithRootViewController: myViewController];
myNavigationController.modalPresentationStyle = UIModalPresentationPageSheet;
[self presentModalViewController: myNavigationController animated:YES];
If say you want a screen overlay, use the parentViewController.view, it will place above navigation bar ++
MyCustomViewController* myOverlayView = [[MyCustomViewController alloc] init];
[self.parentViewController.view addSubview:myOverlayView];
This worked for me:
UIViewController *modalViewController = [[UIViewController alloc] init];
modalViewController.view.backgroundColor = [UIColor whiteColor] colorWithAlpha:0.5];
[self showDetailViewController:modalViewController sender:nil];