When I first load the web view its frame is correct but when I rotate the device, its width is not update.
For instance, if the view was portrait and I rotate it in landscape the web view frame is not cover the whole view.
Loading web view
-(void) viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[self loadWebView];
}
-(void) loadWebView {
UIWebView *webView;
webView = [[UIWebView alloc] initWithFrame: self.view.frame];
NSString *htmlString = [NSString stringWithFormat:#"%#%#%#",html_header_with_files,DetailsHtml,HTML_FOOTER];
[webView loadHTMLString:htmlString baseURL:nil];
[self.view addSubview:webView];
}
First try:
I added a notification to realize the rotation
- (void) orientationChanged:(NSNotification *)note
{
[self.view layoutIfNeeded];
}
Above code did not solve the problem.
Second try
- (void) orientationChanged:(NSNotification *)note
{
[self loadWebView];
}
Above code did not solve the problem.
The view has to be added with auto layout so that it gets laid out properly in all devices with both orientation.
You need to create an extension of UIView and add the below method to make it a reusable code. You can also add the method in the same class if you are not going to use this method anywhere else.
- (void)addSubView:(UIView *)subView belowView:(UIView *)belowView inSuperView:(UIView *)superView {
[superView addSubview:subView];
[superView addConstraint:[NSLayoutConstraint constraintWithItem:subView attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:superView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:0]];
[superView addConstraint:[NSLayoutConstraint constraintWithItem:subView attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:superView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:0]];
[superView addConstraint:[NSLayoutConstraint constraintWithItem:subView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:superView attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0]];
if (nil == belowView) {
[superView addConstraint:[NSLayoutConstraint constraintWithItem:subView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:superView attribute:NSLayoutAttributeTop multiplier:1.0 constant:0]];
} else {
[superView addConstraint:[NSLayoutConstraint constraintWithItem:subView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:belowView attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0]];
}
}
Then you need to call the above method like
[self addSubView:webView belowView:nil inSuperView:self.view];
Note:
To know more about auto-layout you can follow the tutorial
https://www.raywenderlich.com/443-auto-layout-tutorial-in-ios-11-getting-started
Also its better to start writing your app with swift rather than continuing objective-c even if some of your codebase is already in objective-c. A tutorial to make obj-c and swift inter operability can be seen in below link
https://medium.com/ios-os-x-development/swift-and-objective-c-interoperability-2add8e6d6887
Related
I just want the WKWebView to be pinned to all sides of the self.view, so that it will always be stretched as far as possible no matter rotation. Using the following code, it will fill the view for whatever the initial rotation is, but after rotating, it simply all disappears:
-(void)viewWillAppear:(BOOL)animated {
[super viewDidLoad];
self.title = #"Worship Slides";
self.productURL = #"http://www.316apps.com/Fritch/worship.key";
NSURL *url = [NSURL URLWithString:self.productURL];
NSURLRequest *request = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:60.0];
_theWorship = [[WKWebView alloc] initWithFrame:self.view.frame];
[_theWorship setTranslatesAutoresizingMaskIntoConstraints:NO];
[_theWorship loadRequest:request];
_theWorship.frame = CGRectMake(0, 0, self.navigationController.view.bounds.size.width, self.navigationController.view.bounds.size.height);
[self.view addSubview:_theWorship];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_theWorship attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.bottomLayoutGuide attribute:NSLayoutAttributeTop multiplier:1.0 constant:0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_theWorship attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.topLayoutGuide attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_theWorship attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeLeft multiplier:1.0 constant:0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_theWorship attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeRight multiplier:1.0 constant:0]];
}
Get rid of addConstraint and call isActive = true instead. See the documentation:
When developing for iOS 8.0 or later, set the constraint’s active property to true instead of calling the addConstraint(_:) method directly. The isActive property automatically adds and removes the constraint from the correct view.
Alternatively use NSLayoutAnchor; its not as long winded as NSLayoutConstraint. I only use NSLayoutConstraint in a loop or when I cannot express a constraint with NSLayoutAnchor (ie center multiply).
-(void)viewWillAppear:(BOOL)animated {
**[super viewDidLoad];**
Change to:
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
Also make sure you add a method to check if your code has already been called, otherwise it will get called multiple times /everytime the view will appear. You should rather call it from viewDidLoad method instead , but you can choose whatever as long as you don't call it multiple times.
Also , after adding everything you can call:
[_theWorship layoutIfNeeded];
I have a view called profile which is taking (0,0,320,60) size in storyboard which is taking full width but 60 height, and i am trying to place another view called ranking inside it at the center and what ever the device is iPhone4s,5s,6s,6 it should just take my view and put it at the center.
Here is what i tried:
ranking.frame = CGRectMake(0, 0, 120, 60);
ranking.center = self.Profile.center;
The current code is not centering my view In all devices. what can i do to do it dynamically ?
You can use AutoLayout with the following method:
+ (void)centerView:(UIView *)view inContainerView:(UIView *)containerView withSuperView:(UIView *)superView
{
[superView addConstraint:[NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:containerView attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0.0]];
[superView addConstraint:[NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:containerView attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0.0]];
}
You can add the method above in your ViewController or in a helper class.
Remember to set the translatesAutoresizingMaskIntoConstraints property to false before using AutoLayout on your view.
So if ranking is your subview and self.Profile is your superView you can do the following.
UIView *ranking = [[UIView alloc] init];
ranking.translatesAutoresizingMaskIntoConstraints = false;
[self.Profile addSubview:ranking];
[[self class] centerView:ranking inContainerView:self.Profile withSuperView:self.Profile];
[self.Profile addConstraint:[NSLayoutConstraint constraintWithItem:ranking attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1.0 constant:120]];
[self.Profile addConstraint:[NSLayoutConstraint constraintWithItem:ranking attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1.0 constant:60]];
I have problem with setting constraints to custom UIView and pushing new ViewController by delegate when I tap the view. I tried to find solution for these problems but couldn't find one that answers to these questions.
Autolayout problem
I have custom xib-file which has been set Size: Freeform, Width: 600 and Height: 25, it also includes one label and one button with constraints in this view. I have added this view successfully below navigation bar where I want it. Problem is, that it don't make anything to fit it's width equally with navigation bar / window size (I have tried multiple choices eg. making new frame for view that is width of window / navigation bar). It only appears to have static 600 width all the time whatever I try.
First two constraints are working, it appears 25 points below navigation bar and it centers it. But last one won't make anything.
How should I do this properly? So far have this:
[self.subView setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.view addSubview:self.subView];
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:self.subView
attribute:NSLayoutAttributeBottom
relatedBy:NSLayoutRelationEqual
toItem:self.navBar
attribute:NSLayoutAttributeBottom
multiplier:1
constant:25.0]];
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:self.subView
attribute:NSLayoutAttributeCenterX
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeCenterX
multiplier:1.0
constant:0.0]];
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:self.subView
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeWidth
multiplier:1
constant:0]];
Should I do something more with xib-file that it will make this width to fit it's parent view? I have also implemented initWithFrame, initWithCoder and intrinsicContentSize to my custom view.
Solution
I ended up to make containerView for my subView and center it vertically and horizontally and found right constraint for width. I also forgot to update my subView's view frames to match navigation bar width. Here is what I ended up to (if there is better way to do this, I take critic with pleasure):
self.containerView = [[UIView alloc] initWithFrame:CGRectMake(0, 62, self.navBar.frame.size.width, 25)];
[self.view addSubview:self.containerView];
self.subView = [[SubView alloc]init];
[self.subView setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.containerView addSubview:self.subView];
self.subView.view.frame = CGRectMake(0, 0, self.containerView.frame.size.width, self.containerView.frame.size.height);
[self.containerView addConstraint:
[NSLayoutConstraint constraintWithItem:self.subView
attribute:NSLayoutAttributeCenterY
relatedBy:NSLayoutRelationEqual
toItem:self.containerView
attribute:NSLayoutAttributeCenterY
multiplier:1.0
constant:0.0]];
[self.containerView addConstraint:
[NSLayoutConstraint constraintWithItem:self.subView
attribute:NSLayoutAttributeCenterX
relatedBy:NSLayoutRelationEqual
toItem:self.containerView
attribute:NSLayoutAttributeCenterX
multiplier:1.0
constant:0.0]];
[self.containerView addConstraint:
[NSLayoutConstraint constraintWithItem:self.subView
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:self.containerView
attribute:NSLayoutAttributeWidth
multiplier:1.0f
constant:0]];
Delegate problem (solved)
For answer to this problem: check MisterGreen's answer below.
Another problem occured when I made UITapGestureRecognizer with delegate in my custom view. What I want is when I tap the view, it opens another ViewController. The delegate function is like this where I implement my custom view:
-(void)pushViewControllerUsingDelegate
{
NSLog(#"DELEGATE WAS : %#", self.subView.delegate);
[self pushViewController:self.anotherViewController animated:YES];
}
Now it gives exception when I tap the view:
DELEGATE WAS : <MasterViewController: 0x7fc96132e7d0> <-- Delegate is OK
*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<AnotherViewController 0x7fc961248230> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key subViewButton.'
What this actually means? I have this subViewButton IBOutlet with weak property, does it have something to do with this? Or is there another way to make this happen?
Tutorial which I followed: https://www.youtube.com/watch?v=TfKv1MYxnA4
Because there is not enough data to be exactly sure what is the problem you encountered, i have just created a code snippet that is working and doing exactly what you are trying to get.
About the constraints i think the problem is the hight constraint that is missing(unless you determined it elsewhere),
try to remember that when you add constraints provide enough data to the compiler to understand how to resize and position your subview according to it's superview, in your case it didn't know what is the hight cause you didn't supply nor bottom or hight constraint to determine it.
About the delegate method you didn't supply enough data to exactly determine what is the problem, so i've written something that i think is doing what you are trying to get.
This code snippet is tested and working:
The subview:
View.h
#protocol viewManager <NSObject>
#optional
- (void)subviewWasTapped;
#end
#interface View : UIView
#property (nonatomic, strong) id<viewManager>delegate;
#end
View.m
#implementation View
- (void)awakeFromNib{
[super awakeFromNib];
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(viewWasTapped:)];
[self addGestureRecognizer:tap];
}
- (void)viewWasTapped:(NSNotification *)notification
{
[self sendViewWasTappedToDelegate];
}
- (void)sendViewWasTappedToDelegate
{
#synchronized(_delegate)
{
if([_delegate respondsToSelector:#selector(subviewWasTapped)])
{
[_delegate subviewWasTapped];
}
}
}
#end
FirstViewController:
#interface ViewController () <viewManager>
#property (nonatomic, strong) View *subview;
#end
#implementation ViewController
#synthesize subview;
- (void)viewDidLoad {
[super viewDidLoad];
NSArray *subviewArray = [[NSBundle mainBundle] loadNibNamed:#"View" owner:self options:nil];
subview = [subviewArray objectAtIndex:0];
[subview setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.view addSubview:subview];
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:subview
attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationEqual
toItem:self.topLayoutGuide
attribute:NSLayoutAttributeBottom
multiplier:1.0
constant:0.0]];
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:subview
attribute:NSLayoutAttributeCenterX
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeCenterX
multiplier:1.0
constant:0.0]];
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:subview
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeWidth
multiplier:1
constant:0.0]];
// Height constraint to determine the
[self.view addConstraint:
[NSLayoutConstraint constraintWithItem:subview
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:nil
attribute:NSLayoutAttributeNotAnAttribute
multiplier:1
constant:25.0]];
[self.view layoutIfNeeded];
[subview setDelegate:self];
}
#pragma mark - viewManager delegate method
- (void)subviewWasTapped{
SecondeViewController *secondeVC = [self.storyboard instantiateViewControllerWithIdentifier:#"SecondeViewController"];
[self.navigationController pushViewController:secondeVC animated:YES];
}
I have a subview and added 1 button. I want to add this button in the center of that view. I use Autolayout so i need to set the constraints for this button programmatically.
I tried this code but the play button is not in the center.
[self.moviePlayer.view addSubview:self.playbtn];
self.playbtn.translatesAutoresizingMaskIntoConstraints = NO;
[self.moviePlayer.view addConstraint:[NSLayoutConstraint constraintWithItem:self.playbtn attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual
toItem:self.moviePlayer.view attribute:NSLayoutAttributeCenterX multiplier:0.667 constant:0]];
Please help me to correct it. Thanks in advance.
You can use the NSLayoutAttributeCenterX and NSLayoutAttributeCenterY attributes to center your play button like this:
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
[self initViews];
[self initConstraints];
}
-(void)initViews
{
self.picture = [[UIImageView alloc] init];
self.picture.image = [UIImage imageNamed:#"bg"];
self.playButton = [[UIButton alloc] init];
[self.playButton setImage:[UIImage imageNamed:#"playButton"] forState:UIControlStateNormal];
[self.view addSubview:self.picture];
[self.view addSubview:self.playButton];
}
-(void)initConstraints
{
self.picture.translatesAutoresizingMaskIntoConstraints = NO;
self.playButton.translatesAutoresizingMaskIntoConstraints = NO;
id views = #{
#"picture": self.picture,
#"playButton": self.playButton
};
// picture constraints
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"H:|[picture]|" options:0 metrics:nil views:views]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"V:|[picture]|" options:0 metrics:nil views:views]];
// play button constraints
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.playButton attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0.0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.playButton attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0.0]];
}
You get something like this:
You can use this code to center any item (es. self.btn) in its superview:
[self.btn.superview addConstraint:[NSLayoutConstraint
constraintWithItem:self.btn.superview
attribute:NSLayoutAttributeCenterX
relatedBy:NSLayoutRelationEqual
toItem:self.btn
attribute:NSLayoutAttributeCenterX
multiplier:1.0
constant:0.0]];
[self.btn.superview addConstraint:[NSLayoutConstraint
constraintWithItem:self.btn.superview
attribute:NSLayoutAttributeCenterY
relatedBy:NSLayoutRelationEqual
toItem:self.btn
attribute:NSLayoutAttributeCenterY
multiplier:1.0
constant:0.0]];
I also wrote an article about aligning any UIView objects without using Storyboards on my blog.
I have a View Controller containing a view (of another controller) and a tab bar at the bottom. I want to add an iAD banner such that when an ad is loaded and unloaded, the contained view is resized accordingly.
/* AutoLayout */
/* pin Left of child to left of parent */
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:child.view
attribute:NSLayoutAttributeLeft
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeLeft
multiplier:1.0
constant:0]];
/* pin Right of child to right of parent */
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:child.view
attribute:NSLayoutAttributeRight
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeRight
multiplier:1.0
constant:0]];
/* pin top of child to bottom of nav bar(or status bar if no nav bar) */
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:child.view
attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationEqual
toItem:self.topLayoutGuide
attribute:NSLayoutAttributeBottom
multiplier:1.0
constant:0]];
/* pin Top of tab bar to bottom of child view */
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.bottomLayoutGuide
attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationEqual
toItem:child.view
attribute:NSLayoutAttributeBottom
multiplier:1.0
constant:0]];
/*
* adConstraint is an instance variable to hold the constraint I want to animate
* Note that it is not an IBOutlet
*/
adConstraint = [NSLayoutConstraint constraintWithItem:child.view
attribute:NSLayoutAttributeBottom
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeBottom
multiplier:1.0
constant:0];
[self.view addConstraint:adConstraint];
In my delegate methods i have the following
- (void)bannerViewDidLoadAd:(ADBannerView *)banner
{
UIView animateWithDuration:1 animations:^{
adConstraint.constant = -banner.frame.size.height;
[self.view layoutIfNeeded];
}];
}
and
- (void)bannerView:(ADBannerView *)banner didFailToReceiveAdWithError:(NSError *)error
{
UIView animateWithDuration:1 animations:^{
adConstraint.constant = 0;
[self.view layoutIfNeeded];
}];
}
I seriously need help with this! Is it even possible to achieve this without Storyboard and the IBOutlet or am I doing something (terribly) wrong?
Please Help?!
*********************** EDIT: ************************
I've noticed a problem; The ad shows up but bannerDidLoadAd is not called. I know this because I added log statements in it. Does anyone know why this might be happening????
Try calling
[self.view setNeedsUpdateConstraints];
before
[self.view layoutIfNeeded];
It should work!
[UIView animateWithDuration:1 animations:^{
adConstraint.constant = 0;
[self.view setNeedsUpdateConstraints];
[self.view layoutIfNeeded];
}];