MBProgressHUD & SDWebImage - HUD not showing - objective-c

I'm using SDWebImagePrefetcher to prefetch a list of images off my plist.
I was editing the method trying to alloc a UIViewController which would have shown an MBProgressHUD HUD to indicate the progress.
Problem is that the HUD won't show in any way. Plus, SDWebImagePrefetcher is a NSObject and I don't really know where to init my custom UIViewController and the HUD, due it doesn't have any viewDidLoad or viewWillAppear methods.
I tried to do something like
MyCustomViewController *cv = [[MyCustomViewController alloc]init];
HUD = [[MBProgressHUD alloc]initInView:cv.view];
and didn't work.
I also tried to add an UIAlertView as subView of the viewController in order to see if it worked but it didn't work at all!
Any advice on where to init an UIViewController in a NSObject class in order to show an HUD on the allocated controller would be awesome.

If you want to display a MBProgressHUD from any class it's simple. Just add it to your application's keyWindow. This is the very top level window for your application and it easy to access from anywhere.
UIWindow *keyWindow = [[UIApplication sharedApplication] keyWindow];
MBProgressHUD *hud = [MBProgressHUD showHUDAddedTo:keyWindow animated:YES];
hud.labelText = #"Loading";
And when you want to hide the MBProgressHUD just use
[hud hide:YES];
Make sure you wait to access the keyWindow until your app's main window has been set up. This occurs at launch. If it is setup programmatically it is in your AppDelegate by calling [window makeKeyAndVisible].

Related

close modalvew controller and parentview

I am trying to open a modalview from a view like that,
SignupViewController *signUpView = [[SignupViewController alloc] initWithNibName:#"SignupViewController" bundle:nil];
[signUpView setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
self.parentViewController.view.transform = CGAffineTransformMakeScale(1.3, 1.3);
self.parentViewController.view.alpha = 0;
[UIView animateWithDuration:.35 animations:^{self.parentViewController.view.alpha = 1.0; self.parentViewController.view.transform = CGAffineTransformMakeScale(1, 1);}];
[self presentModalViewController:signUpView animated:YES];
After login i am closing the modalview and redirecting to anther view, but the parentview is still there,
[self dismissViewControllerAnimated:YES completion:^{
ToolsViewController *gototoolpage = [[ToolsViewController alloc] initWithNibName:#"ToolsViewController" bundle:nil];
[self.navigationController pushViewController:gototoolpage animated:YES];
}
How to dismiss the parentview also. Any idea
You code looks a little confused. What do you intend by references to parentViewController? Check the docs - it is the containing viewController, not the previous or presenting viewController. In a NavigationController context this would be the UINavigationController. In a modal view context there is no parentViewController, but there is a presenting ViewController. I am not sure what you intend by all of those calls to self.parentViewController.
In any case you should really be sending the dismiss request back to your presenting viewController via a delegate so that it is completely clear where the pushViewController message is being passed from and to.
In the header file of your signUpViewController declare a protocol:
#protocol SignUpViewControllerDelegate
- (void) dissmissSignUpVC;
#end
then in your presentingViewController, after
SignupViewController *signUpView = [[SignupViewController alloc] initWithNibName:#"SignupViewController" bundle:nil];
add
[signUpView setDelegate:self];
and implement the delegate method with the same code you now have in your completion block:
- (void) dissmissSignUpVC {
ToolsViewController *gototoolpage = [[ToolsViewController alloc]
initWithNibName:#"ToolsViewController" bundle:nil];
[self.navigationController pushViewController:gototoolpage animated:YES];
}
In signUpView invoke the delegate's method to dismiss:
[[self delegate] dissmissSignUpVC];
Watch out for those stacked animations, I suspect that only the first will be performed (i.e. gototollpage animated:YES might as well be gototoolpage animated:NO)
Perhaps anyway you should reconsider your logic. I imagine the user might have a confusing experience if you do this under-the-hood manipulation of viewControllers. Better that there is a UI control for the user to navigate to toolsViewController so they understand where they are?

How do I implement a UINavigationController in this case?

current version of my project :
I have 5 different UIViewControllers in my app. I've set my
FirstViewController to be the Initial View Controller using the
Attributes Inspector. I move back and forth from one ViewController to
another by using buttons to which I assign modal segues, from one
ViewController to another, using the StoryBoard
What I want to change:
I want to keep the navigation buttons obviously, delete the modal segues and use
a UINavigationController instead. If I understand the concept
correctly, when using a UINavigationController I need to go into each
UIButton-IBAction and at the very end of the method I have to push the next
ViewController I want to move to, onto my NavigationController (do I also
have to pop the current one first?). However, I can't figure out how
to implement all that correctly.
What I've done so far:
I removed all modal segues from the storyboard and kept the navigation buttons along with their corresponding IBActions
I unchecked the box in the Attributes Inspector that was making my FirstViewController the initial View Controller of my app
I went into my AppDelegate.m and tried to create the Navigation Controller there and make my FirstViewController be the RootViewController
MyAppDelegate.m
-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
UIViewController *myFirstViewController = [[FirstViewController alloc] init];
UINavigationController *myNavigationController = [[UINavigationController alloc] initWithRootViewController:myFirstViewController];
[myNavigationController pushViewController:myFirstViewController animated:YES];
// Override point for customization after application launch.
return YES;
}
I then tried to test if the above was working by going into the IBAction of a
navigation button on my FirstViewController and implemented the
following in order to move to my SecondViewController when the
button is pressed :
FirstViewController.m
- (IBAction)goRightButton:(UIButton *)sender
{
// some code drawing the ButtonIsPressed UIImageView on the current View Controller
UIViewController *mySecondViewController = [[SecondViewController alloc] init];
[self.navigationController pushViewController:mySecondViewController animated:YES];
}
but nothing happens. What am I doing wrong ?
You are not linking your XIB file. Please add your navigation controller as
UIViewController *myFirstViewController = [[FirstViewController alloc] initWithNibName:#"FirstViewController" bundle:nil];
navigationController = [[UINavigationController alloc] initWithRootViewController:myFirstViewController];
Use following code to move from one view to another
UIViewController *mySecondViewController = [[SecondViewController alloc] initWithNibName:#"SecondViewController" bundle:nil];
[self.navigationController pushViewController:mySecondViewController animated:YES];
If you are using a storyboard, you should just drag in the navigation controller there and hook it up to your app delegates. As long as it is the main storyboard, and you have identified a view controller to load first, you do not need to load any views in your app delegate.
In order to push a view programmatically that's in a storyboard, you need to do something like the following:
//bundle can be nil if in main bundle, which is default
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
MyCustomViewController *customVC = (MyCustomViewController *)[mainStoryboard instantiateViewControllerWithIdentifier:#"customVC"];
//standard way
[self.navigationController pushViewController:customVC animated:YES];
//custom animation
[UIView transitionWithView:self.navigationController.view duration:0.5 options:UIViewAnimationOptionTransitionCurlUp animations:^{
[self.navigationController pushViewController:customVC animated:NO];
} completion:nil];
You identify the view controller with the identifier you add in the storyboard editor. Below are some screenshots to help show what I mean.

UIPageViewControllerSpineLocation Delegate Method Not Firing

Major head-scratcher all day on this one :-(
I have an instance of a UIPageViewController that does not appear to be firing the delegate method:
-(UIPageViewControllerSpineLocation)pageViewController:(UIPageViewController *)pageViewController
spineLocationForInterfaceOrientation:(UIInterfaceOrientation)orientation
I have tried various methods of displaying the UIPageViewController and have settled on a programatic approach (as opposed to a Storyboard one) that appears to be working correctly, with one exception... when rotating the iPad to landscape the spine does not appear mid-point as expected. I simply cannot find out why the delegate method does not get called.
Code Explanation (simplified for example)
Consider three classes as follows:
RootViewController - loaded when the app starts
PageViewController - loaded by RootViewController upon user initiation
PageContentViewController - loaded by PageViewController when pages are needed
Fairly self-explanatory. The RootViewController is loaded by the app upon launch. When the user taps an image within this view controller's view (think magazine cover opening a magazine) it launches the PageViewController as follows:
PageViewController *pvc = [[PageViewController alloc] initWithNibName:#"PageView"
bundle:[NSBundle mainBundle]];
pvc.view.frame = self.view.bounds;
[self.view addSubview:pvc.view];
In the actual app there is animation etc to make the transition all nice, but essentially the PageViewController's view is loaded and takes fullscreen.
PageViewController
This is the workhorse (only relevant methods shown). I have tried various examples from the infinite world of Google and written directly from the Apple docs...
#interface PageViewController : UIViewController <UIPageViewControllerDelegate, UIPageViewControllerDataSource>
#property (nonatomic, strong) UIPageViewController *pageViewController;
#property (nonatomic, strong) NSMutableArray *modelArray;
#end
#implementation TXCategoryController
-(void)viewDidLoad
{
[super viewDidLoad];
// Simple model for demo
self.modelArray = [NSMutableArray alloc] init];
for (int i=1; i<=20; i++)
[self.modelArray addObject:[NSString stringWithFormat:#"Page: %d", i]];
self.pageViewController = [[UIPageViewController alloc]
initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl
navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options:nil];
self.pageViewController.delegate = self;
self.pageViewController.dataSource = self;
PageContentViewController *startupVC = [[PageContentViewController alloc] initWithNibName:#"PageContent" bundle:nil];
startupVC.pageLabel = [self.modelArray objectAtIndex:0];
[self.pageViewController setViewControllers:[NSArray arrayWithObject:startupVC]
direction:UIPageViewControllerNavigationDirectionForward
animated:NO
completion:nil];
[self addChildViewController:self.pageViewController];
[self.view addSubview:self.pageViewController.view];
[self.pageViewController didMoveToParentViewController:self];
self.pageViewController.view.frame = self.view.bounds;
self.view.gestureRecognizers = self.pageViewController.gestureRecognizers;
}
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerBeforeViewController:(UIViewController *)viewController
{
// Relevant code to add another view...
}
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerAfterViewController:(UIViewController *)viewController
{
// Relevant code to add another view...
}
-(UIPageViewControllerSpineLocation)pageViewController:(UIPageViewController *)pageViewController
spineLocationForInterfaceOrientation:(UIInterfaceOrientation)orientation
{
// Setting a break point in here - never gets called
if (UIInterfaceOrientationIsPortrait(orientation))
{
// Relevant code to create view...
return UIPageViewControllerSpineLocationMin;
}
// Relevant code to create 2 views for side-by-side display and
// set those views using self.pageViewController setViewControllers:
return UIPageViewControllerSpineLocationMid
}
#end
This all works perfectly well as I mentioned earlier. The PageViewController's view gets shown. I can swipe pages left and right in both portrait and landscape and the respective page number appears. However, I don't ever see two pages side-by-side in landscape view. Setting a breakpoint in the spineLocationForInterfaceOrientation delegate method never gets called.
This is such a head-scratcher I have burned out of ideas on how to debug/solve the problem. It almost behaves like the UIPageViewController isn't responding to the orientation changes of the device and therefore isn't firing off the delegate method. However, the view gets resized correctly (but that could be just the UIView autoresizing masks handling that change).
If I create a brand new project with just this code (and appropriate XIb's etc) it works perfectly fine. So something somewhere in my actual project is causing this. I have no idea where to continue looking.
As usual, any and all help would be very much appreciated.
Side Note
I wanted to add the tag 'uipageviewcontrollerspinelocation' but couldn't because it was too long and I didn't have enough reputation (1500 required). I think this is a devious ploy on Apple's part to avoid certain tags in Stackoverflow... ;-)
Finally found the problem. It was something of a red herring in its symptoms, but related just the same.
Putting a break point in the shouldAutorotateToInterfaceOrientation: method was a natural test to see if the UIViewController was even getting a rotation notification. It wasn't which led me to Apple's technical Q&A on the issue: http://developer.apple.com/library/ios/#qa/qa1688/_index.html
The most relevant point in there was:
The view controller's UIView property is embedded inside UIWindow but alongside an additional view controller.
Unfortunately, Apple, in its traditional documentation style, doesn't provide an answer, merely confirmation of the problem. But an answer on Stack Overflow yielded the next clue:
Animate change of view controllers without using navigation controller stack, subviews or modal controllers?
Although my RootViewController was loading the PageViewController, I was doing it as a subview to the main view. This meant I had two UIViewController's in which only the parent would respond to changes.
The solution to get the PageViewController to listen to the orientation changes (thus triggering the associated spine delegate method) was to remove addSubview: and instead present the view controller from RootViewController:
[self presentViewController:pac animated:YES completion:NULL];
Once that was done, the orientation changes were being picked up and the PageViewController was firing the delegate method for spine position. Only one minor detail to consider. If the view was launched in landscape, the view was still displaying portrait until rotated to portrait and back to landscape.
That was easily tweaked by editing viewDidLoad as follows:
PageContentViewController *page1 = [[PageContentViewController alloc] initWithNibName:#"PageContent" bundle:nil];
NSDictionary *pageViewOptions = nil;
NSMutableArray *pagesArray = [NSMutableArray array];
if (IS_IPAD && UIInterfaceOrientationIsLandscape(self.interfaceOrientation))
{
pageViewOptions = [NSDictionary dictionaryWithObject:[NSNumber numberWithInt:UIPageViewControllerSpineLocationMid]
forKey:UIPageViewControllerOptionSpineLocationKey];
PageContentViewController *page2 = [[PageContentViewController alloc] initWithNibName:#"PageContent" bundle:nil];
[pagesArray addObject:page1];
[pagesArray addObject:page2];
}
else
{
[pagesArray addObject:page1];
}
self.pageViewController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl
navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal
options:pageViewOptions];
self.pageViewController.delegate = self;
[self.pageViewController setViewControllers:pagesArray
direction:UIPageViewControllerNavigationDirectionForward
animated:NO
completion:NULL];
Job done and problem solved.

Going back to first ViewController from second ViewController

I'm building an app that currently has 3 ViewControllers. One of them is used after a successful login so is not relevant in this question.
I'm using a mixture of Storyboards and building things programmatically when I find Storyboards do not give me the fine control that I need.
The first ViewController is built in my 'MainStoryboard'. It has a login form and an info button at the bottom. I link it up the my AppDelegate by doing the following inside didFinishLaunchingWithOptions:
ViewController *viewController = (ViewController *)self.window.rootViewController;
Because I wanted to force rendering of a UIWebView (another story) I create the second view programmatically. I do the following inside didFinishLaunchingWithOptions:
infoViewController = [[InfoViewController alloc] init];
[infoViewController view];
Inside both of my ViewControllers I setup a link to appDelegate as below:
appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
I have an info button in my first ViewController that takes you to the infoViewController. It calls the following code when tapped:
appDelegate.infoViewController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:appDelegate.infoViewController animated:YES];
The above works just fine for me, flips over the screen and shows the InfoViewController.
On my InfoViewController I have a button that should take you back to the login page, I have tried all sorts to get this to work but it just crashes my app. Nothing seems to work. I have tried the following:
appDelegate.viewController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:appDelegate.viewController animated:YES];
and
[self.navigationController popToRootViewControllerAnimated:YES];
and
[self.navigationController popViewControllerAnimated:YES];
and
[self.navigationController popToViewController:appDelegate.viewController animated:YES];
I suspect the last 3 might be more to do with when you have a navigation view controller and you want to go back to the root? I'm not sure, but either way it does not work. I had this working using storyboards previously so I'm sure it ought to be easy! As mentioned I switched to making the infoViewController programmatically so that I could force the UIWebView to render before the view appeared.
Any help much appreciated.
You can do with:
[self dismissModalViewControllerAnimated:YES];
You should use this.
[self dismissModalViewControllerAnimated:YES];
You should use a main controller for switching between your other view controllers. Change the view of your root controller to one of your other view controllers (apply animations as usual if needed). Hold a pointer to your root controller in your other view controllers and call self.rootController.view = <desired_controller_instance>.view
I think the way you're presenting your InfoViewController is wrong. Do it the following way:
In your ViewController, create an action for the info button.:
- (IBAction)infoButtonTapped:(id)sender
{
InfoViewController *infoViewController = [[InfoViewController alloc] init];
infoViewController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:infoViewController animated:YES];
}
And in your InfoViewController, in the action of your button that should take you back write this:
- (void)takeBackToViewController
{
[self dismissModalViewControllerAnimated:YES];
}
Hope it works.
Also in presented controller you can use this
if(self.parentViewController)
[self.parentViewController dismissModalViewControllerAnimated:YES];
else
[self.presentingViewController dismissModalViewControllerAnimated:YES];
To dissmiss current controller.

UISplitViewController programmatically without nib/xib

I usually create my projects without IB-stuff. The first thing I do is to strip off all references to xibs, outlets updated plist, etc and so forth. No problems, works great (in my world)!
Now, I just installed 3.2 and tried to develop my first iPad app. Following same procedure as before, I created a UISplitView-based application project and stripped off all IB-stuff. Also, I followed the section in Apple's reference docs: Creating a Split View Controller Programmatically, but nevertheless, the Master-view is never shown, only the Detail-view is (no matter what the orientation is). I really have tried to carefully look this through but I cannot understand what I have missed.
Is there a working example of a UISplitViewController without the nibs floating around somewhere? I have googled but could not find any. Or do you know what I probably have missed?
Declare your splitviewcontroller in your delegate header, use something like this in your didfinishlaunching
ensure you add the UISplitViewControllerDelegate to the detailedViewController header file and that you have the delegate methods aswell. remember to import relevant header files
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
splitViewController = [[UISplitViewController alloc] init];
rootViewController *root = [[rootViewController alloc] init];
detailedViewController *detail = [[detailedViewController alloc] init];
UINavigationController *rootNav = [[UINavigationController alloc] initWithRootViewController:root];
UINavigationController *detailNav = [[UINavigationController alloc] initWithRootViewController:detail];
splitViewController.viewControllers = [NSArray arrayWithObjects:rootNav, detailNav, nil];
splitViewController.delegate = detail;
[window addSubview:splitViewController.view];
EDIT - as per Scott's excellent suggestion below, don't add to the windows subview, instead
[self.window setRootViewController:(UIViewController*)splitViewController]; // that's the ticket
[window makeKeyAndVisible];
return YES;
}
//detailedView delegate methods
- (void)splitViewController:(UISplitViewController*)svc
willHideViewController:(UIViewController *)aViewController
withBarButtonItem:(UIBarButtonItem*)barButtonItem
forPopoverController:(UIPopoverController*)pc
{
[barButtonItem setTitle:#"your title"];
self.navigationItem.leftBarButtonItem = barButtonItem;
}
- (void)splitViewController:(UISplitViewController*)svc
willShowViewController:(UIViewController *)aViewController
invalidatingBarButtonItem:(UIBarButtonItem *)barButtonItem
{
self.navigationItem.leftBarButtonItem = nil;
}
I also prefer code to IB ;-)
Oldish thread, but thought I'd spare reader time + grief when the above technique fails to produce a UISplitViewController that responds correctly to device orientation change events. You'll need to:
Ensure all subordinate views respond properly in
shouldAutorotateToInterfaceOrientation. Nothing new here.
Rather than add the UISplitViewController's view to the main window,
[window addSubview:splitViewController.view]; // don't do this
instead set the main window's root controller to the UISplitViewController:
[self.window setRootViewController:(UIViewController*)splitViewController]; // that's the ticket
Adding the splitviewcontroller's view as a subview of the main window (barely) allows it to co-present with sibling views, but it doesn't fly with UISplitViewController's intended use case. A UISplitViewController is a highlander view; there can only be one.
Swift 5.2
iOS 13
Both master and detail view controllers are embedded in navigation controllers
let splitViewController = UISplitViewController()
splitViewController.delegate = self
let masterVC = MasterViewController()
let detailVC = DetailViewController()
let masterNavController = UINavigationController(rootViewController: masterVC)
let detailNavController = UINavigationController(rootViewController: detailVC)
splitViewController.viewControllers = [masterNavController,detailNavController]
You can put this code in your AppDelegate's (or in SceneDelegate if your target is iOS 13.0+)didFinishLaunchingWithOptions function. Just remember to make the splitViewController your rootViewController like this
self.window!.rootViewController = splitViewController
I had just met the same problem.
make sure that your child viewController of splitview can Autorotate to interface orientation.
you can change the function in your childViewController like this:
-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
return YES;
}
then the master view will be shown.