I'm trying to make a fullpage component in Angular :
I want each sections take a 100% height of my screen, and when I scroll in a section (up or down) it goes to the next / previous section. I declared this function to do that, and it works :
#HostListener('wheel', ['$event'])
onScroll(event: WheelEvent) {
if (event.deltaY < 0) {
this.slidePrev();
} else {
this.slideNext();
}
}
Now, I want to update a little to slide to the previous slide only if the scrollbar is on the top, or slide to the next only if the scrollbar is to the bottom. I Used JQuery to do that, this way :
#HostListener('mousewheel', ['$event'])
onScroll(event: WheelEvent) {
if (this.isSliding) {
event.preventDefault();
return;
}
let $section = $(event.target).closest(".section");
//$section.css("opacity", "0.99");
//setTimeout(() => {
// $section.css("opacity", "1");
//}, 100);
if (event.deltaY < 0) {
if ($section.scrollTop() == 0) this.slidePrev();
} else {
if ($section.scrollTop() == $section.prop("scrollHeight") - $section.height()) this.slideNext();
}
}
It works the first time, but if I slide down to the next slide, when I want to sroll to move my scrollbar, it doesn't move.
I noticed that after the website trigger an update (example : css :hover event that update style) the scrollbar move again. So, if I uncomment my 4 commented lines, it works again because the style is updated.
Can someone tell me why ? And is there a better way to fix that issue ?
EDIT :
in slideNext() and slidePrev() I'm using $().animate("scrollTop", ...) function, and it's the function that breaks my scroll
Short version:
I am having a problem with auto layout top layout guide when used in conjunction with custom transition and UINavigationController in iOS7. Specifically, the constraint between the top layout guide and the text view is not being honored. Has anyone encountered this issue?
Long version:
I have a scene which has unambiguously define constraints (i.e. top, bottom, left and right) that renders a view like so:
But when I use this with a custom transition on the navigation controller, the top constraint to the top layout guide seems off and it renders is as follows, as if the top layout guide was at the top of the screen, rather than at the bottom of the navigation controller:
It would appear that the "top layout guide" with the navigation controller is getting confused when employing the custom transition. The rest of the constraints are being applied correctly. And if I rotate the device and rotate it again, everything is suddenly rendered correctly, so it does not appear to be not a matter that the constraints are not defined properly. Likewise, when I turn off my custom transition, the views render correctly.
Having said that, _autolayoutTrace is reporting that the UILayoutGuide objects suffer from AMBIGUOUS LAYOUT, when I run:
(lldb) po [[UIWindow keyWindow] _autolayoutTrace]
But those layout guides are always reported as ambiguous whenever I look at them even though I've ensured that there are no missing constraints (I've done the customary selecting of view controller and choosing "Add missing constraints for view controller" or selecting all of the controls and doing the same for them).
In terms of how precisely I'm doing the transition, I've specified an object that conforms to UIViewControllerAnimatedTransitioning in the animationControllerForOperation method:
- (id<UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationController
animationControllerForOperation:(UINavigationControllerOperation)operation
fromViewController:(UIViewController*)fromVC
toViewController:(UIViewController*)toVC
{
if (operation == UINavigationControllerOperationPush)
return [[PushAnimator alloc] init];
return nil;
}
And
#implementation PushAnimator
- (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext
{
return 0.5;
}
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext
{
UIViewController* toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UIViewController* fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
[[transitionContext containerView] addSubview:toViewController.view];
CGFloat width = fromViewController.view.frame.size.width;
toViewController.view.transform = CGAffineTransformMakeTranslation(width, 0);
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
fromViewController.view.transform = CGAffineTransformMakeTranslation(-width / 2.0, 0);
toViewController.view.transform = CGAffineTransformIdentity;
} completion:^(BOOL finished) {
fromViewController.view.transform = CGAffineTransformIdentity;
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
}];
}
#end
I've also done a rendition of the above, setting the frame of the view rather than the transform, with the same result.
I've also tried manually make sure that the constraints are re-applied by calling layoutIfNeeded. I've also tried setNeedsUpdateConstraints, setNeedsLayout, etc.
Bottom line, has anyone successfully married custom transition of navigation controller with constraints that use top layout guide?
Managed to fix my issue by adding this line:
toViewController.view.frame = [transitionContext finalFrameForViewController:toViewController];
To:
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext fromVC:(UIViewController *)fromVC toVC:(UIViewController *)toVC fromView:(UIView *)fromView toView:(UIView *)toView {
// Add the toView to the container
UIView* containerView = [transitionContext containerView];
[containerView addSubview:toView];
[containerView sendSubviewToBack:toView];
// animate
toVC.view.frame = [transitionContext finalFrameForViewController:toVC];
NSTimeInterval duration = [self transitionDuration:transitionContext];
[UIView animateWithDuration:duration animations:^{
fromView.alpha = 0.0;
} completion:^(BOOL finished) {
if ([transitionContext transitionWasCancelled]) {
fromView.alpha = 1.0;
} else {
// reset from- view to its original state
[fromView removeFromSuperview];
fromView.alpha = 1.0;
}
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
}];
}
From Apple's Documentation for [finalFrameForViewController] : https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIViewControllerContextTransitioning_protocol/#//apple_ref/occ/intfm/UIViewControllerContextTransitioning/finalFrameForViewController:
I solved this by fixing the height constraint of the topLayoutGuide. Adjusting edgesForExtendedLayout wasn't an option for me, as I needed the destination view to underlap the navigation bar, but also to be able to layout subviews using topLayoutGuide.
Directly inspecting the constraints in play shows that iOS adds a height constraint to the topLayoutGuide with value equal to the height of the navigation bar of the navigation controller. Except, in iOS 7, using a custom animation transition leaves the constraint with a height of 0. They fixed this in iOS 8.
This is the solution I came up with to correct the constraint (it's in Swift but the equivalent should work in Obj-C). I've tested that it works on iOS 7 and 8.
func animateTransition(transitionContext: UIViewControllerContextTransitioning) {
let fromView = transitionContext.viewControllerForKey(UITransitionContextFromViewControllerKey)!.view
let destinationVC = transitionContext.viewControllerForKey(UITransitionContextToViewControllerKey)!
destinationVC.view.frame = transitionContext.finalFrameForViewController(destinationVC)
let container = transitionContext.containerView()
container.addSubview(destinationVC.view)
// Custom transitions break topLayoutGuide in iOS 7, fix its constraint
if let navController = destinationVC.navigationController {
for constraint in destinationVC.view.constraints() as [NSLayoutConstraint] {
if constraint.firstItem === destinationVC.topLayoutGuide
&& constraint.firstAttribute == .Height
&& constraint.secondItem == nil
&& constraint.constant == 0 {
constraint.constant = navController.navigationBar.frame.height
}
}
}
// Perform your transition animation here ...
}
I struggled with the exact same problem. Putting this in the viewDidLoad of my toViewController really helped me out:
self.edgesForExtendedLayout = UIRectEdgeNone;
This did not solve all my issues and I'm still looking for a better approach, but this certainly made it a bit easier.
Just put the following code toviewDidLoad
self.extendedLayoutIncludesOpaqueBars = YES;
FYI, I ended up employing a variation of Alex's answer, programmatically changing the top layout guide's height constraint constant in the animateTransition method. I'm only posting this to share the Objective-C rendition (and eliminate the constant == 0 test).
CGFloat navigationBarHeight = toViewController.navigationController.navigationBar.frame.size.height;
for (NSLayoutConstraint *constraint in toViewController.view.constraints) {
if (constraint.firstItem == toViewController.topLayoutGuide
&& constraint.firstAttribute == NSLayoutAttributeHeight
&& constraint.secondItem == nil
&& constraint.constant < navigationBarHeight) {
constraint.constant += navigationBarHeight;
}
}
Thanks, Alex.
As #Rob mentioned, topLayoutGuide is not reliable when using custom transitions in UINavigationController. I worked around this by using my own layout guide. You can see the code in action in this demo project. Highlights:
A category for custom layout guides:
#implementation UIViewController (hp_layoutGuideFix)
- (BOOL)hp_usesTopLayoutGuideInConstraints
{
return NO;
}
- (id<UILayoutSupport>)hp_topLayoutGuide
{
id<UILayoutSupport> object = objc_getAssociatedObject(self, #selector(hp_topLayoutGuide));
return object ? : self.topLayoutGuide;
}
- (void)setHp_topLayoutGuide:(id<UILayoutSupport>)hp_topLayoutGuide
{
HPLayoutSupport *object = objc_getAssociatedObject(self, #selector(hp_topLayoutGuide));
if (object != nil && self.hp_usesTopLayoutGuideInConstraints)
{
[object removeFromSuperview];
}
HPLayoutSupport *layoutGuide = [[HPLayoutSupport alloc] initWithLength:hp_topLayoutGuide.length];
if (self.hp_usesTopLayoutGuideInConstraints)
{
[self.view addSubview:layoutGuide];
}
objc_setAssociatedObject(self, #selector(hp_topLayoutGuide), layoutGuide, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
#end
HPLayoutSupport is the class that will act as a layout guide. It has to be a UIView subclass to avoid crashes (I wonder why this isn't part of the UILayoutSupport interface).
#implementation HPLayoutSupport {
CGFloat _length;
}
- (id)initWithLength:(CGFloat)length
{
self = [super init];
if (self)
{
self.translatesAutoresizingMaskIntoConstraints = NO;
self.userInteractionEnabled = NO;
_length = length;
}
return self;
}
- (CGSize)intrinsicContentSize
{
return CGSizeMake(1, _length);
}
- (CGFloat)length
{
return _length;
}
#end
The UINavigationControllerDelegate is the one responsible for "fixing" the layout guide before the transition:
- (id <UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationController
animationControllerForOperation:(UINavigationControllerOperation)operation
fromViewController:(UIViewController *)fromVC
toViewController:(UIViewController *)toVC
{
toVC.hp_topLayoutGuide = fromVC.hp_topLayoutGuide;
id <UIViewControllerAnimatedTransitioning> animator;
// Initialise animator
return animator;
}
Finally, the UIViewController uses hp_topLayoutGuide instead of topLayoutGuide in the constraints, and indicates this by overriding hp_usesTopLayoutGuideInConstraints:
- (void)updateViewConstraints
{
[super updateViewConstraints];
id<UILayoutSupport> topLayoutGuide = self.hp_topLayoutGuide;
// Example constraint
NSDictionary *views = NSDictionaryOfVariableBindings(_imageView, _dateLabel, topLayoutGuide);
NSArray *constraints = [NSLayoutConstraint constraintsWithVisualFormat:#"V:|[topLayoutGuide][_imageView(240)]-8-[_dateLabel]" options:NSLayoutFormatAlignAllCenterX metrics:nil views:views];
[self.view addConstraints:constraints];
}
- (BOOL)hp_usesTopLayoutGuideInConstraints
{
return YES;
}
Hope it helps.
i found way. First uncheck "Extend Edges" property of controller. after that navigation bar getting dark color. Add a view to controller and set top and bottom LayoutConstraint -100. Then make view's clipsubview property no (for navigaionbar transculent effect). My english bad sory for that. :)
I had the same problem, ended up implementing my own topLayout guide view and making constraints to it rather then to topLayoutGuide. Not ideal. Only posting it here in case someone is stuck and looking for quick hacky solution http://www.github.com/stringcode86/SCTopLayoutGuide
Here's the simple solution I'm using that's working great for me: during the setup phase of - (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext, manually set your "from" and "to" viewController.view.frame.origin.y = navigationController.navigationBar.frame.size.height. It'll make your auto layout views position themselves vertically as you expect.
Minus the pseudo-code (e.g. you probably have your own way of determining if a device is running iOS7), this is what my method looks like:
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext
{
UIViewController *fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
UIViewController *toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UIView *container = [transitionContext containerView];
CGAffineTransform destinationTransform;
UIViewController *targetVC;
CGFloat adjustmentForIOS7AutoLayoutBug = 0.0f;
// We're doing a view controller POP
if(self.isViewControllerPop)
{
targetVC = fromViewController;
[container insertSubview:toViewController.view belowSubview:fromViewController.view];
// Only need this auto layout hack in iOS7; it's fixed in iOS8
if(_device_is_running_iOS7_)
{
adjustmentForIOS7AutoLayoutBug = toViewController.navigationController.navigationBar.frame.size.height;
[toViewController.view setFrameOriginY:adjustmentForIOS7AutoLayoutBug];
}
destinationTransform = CGAffineTransformMakeTranslation(fromViewController.view.bounds.size.width,adjustmentForIOS7AutoLayoutBug);
}
// We're doing a view controller PUSH
else
{
targetVC = toViewController;
[container addSubview:toViewController.view];
// Only need this auto layout hack in iOS7; it's fixed in iOS8
if(_device_is_running_iOS7_)
{
adjustmentForIOS7AutoLayoutBug = toViewController.navigationController.navigationBar.frame.size.height;
}
toViewController.view.transform = CGAffineTransformMakeTranslation(toViewController.view.bounds.size.width,adjustmentForIOS7AutoLayoutBug);
destinationTransform = CGAffineTransformMakeTranslation(0.0f,adjustmentForIOS7AutoLayoutBug);
}
[UIView animateWithDuration:_animation_duration_
delay:_animation_delay_if_you_need_one_
options:([transitionContext isInteractive] ? UIViewAnimationOptionCurveLinear : UIViewAnimationOptionCurveEaseOut)
animations:^(void)
{
targetVC.view.transform = destinationTransform;
}
completion:^(BOOL finished)
{
[transitionContext completeTransition:([transitionContext transitionWasCancelled] ? NO : YES)];
}];
}
A couple of bonus things about this example:
For view controller pushes, this custom transition slides the pushed toViewController.view on top of the unmoving fromViewController.view. For pops, fromViewController.view slides off to the right and reveals an unmoving toViewController.view under it. All in all, it's just a subtle twist on the stock iOS7+ view controller transition.
The [UIView animateWithDuration:...] completion block shows the correct way to handle completed & cancelled custom transitions. This tiny tidbit was a classic head-slap moment; hope it helps somebody else out there.
Lastly, I'd like to point out that as far as I can tell, this is an iOS7-only issue that has been fixed in iOS8: my custom view controller transition that is broken in iOS7 works just fine in iOS8 without modification. That being said, you should verify that this is what you're seeing too, and if so, only run the fix on devices running iOS7.x. As you can see in the code example above, the y-adjustment value is 0.0f unless the device is running iOS7.x.
I ran into this same issue but without using a UINavigationController and just positioning a view off of the topLayoutGuide. The layout would be correct when first displayed, a transition would take place to another view, and then upon exiting and returning to the first view, the layout would be broken as that topLayoutGuide would no longer be there.
I solved this problem by capturing the safe area insets prior to the transition and then reimplementing them, not by adjusting my constraints, but by setting them on the viewController's additionalSafeAreaInsets.
I found this solution to work well as I don't have to adjust any of my layout code and search through constraints and I can just reimplementing the space that was there previously. This could be more difficult if you are actually using the additionalSafeAreaInsets property.
Example
I added a variable to my transitionManager to capture the safe insets that exist when the transitionManager is created.
class MyTransitionManager: NSObject, UIViewControllerAnimatedTransitioning, UIViewControllerTransitioningDelegate {
private var presenting = true
private var container:UIView?
private var safeInsets:UIEdgeInsets?
...
Then during the entering transition I save those insets.
let toView = viewControllers.to.view
let fromView = viewControllers.from.view
if #available(iOS 11.0, *) {
safeInsets = toView.safeAreaInsets
}
In the case of the iPhone X this looks something like UIEdgeInsets(top: 44.0, left: 0.0, bottom: 34.0, right: 0.0)
Now when exiting, the insets on that same view we transitioned from in the entrance will be .zero so we add our captured insets to the additionalSafeAreaInsets on the viewController, which will set them on our view for us as well as update the layout. Once our animation is done, we reset the additionalSafeAreaInsets back to .zero.
if #available(iOS 11.0, *) {
if safeInsets != nil {
viewControllers.to.additionalSafeAreaInsets = safeInsets!
}
}
...then in the animation completion block
if #available(iOS 11.0, *) {
if self.safeInsets != nil {
viewControllers.to.additionalSafeAreaInsets = .zero
}
}
transitionContext.completeTransition(true)
try :
self.edgesforextendedlayout=UIRectEdgeNone
Or just set navigationbar opaque and set background image or backgroundcolor to navigationbar
In storyboard add another vertical constraint to main view's top. I have the same problem too but adding that constraint help me to avoid manual constraints. See screenshot here link
Other solution is to calculate toVC frame... something like this:
float y = toVC.navigationController.navigationBar.frame.origin.y + toVC.navigationController.navigationBar.frame.size.height;
toVC.view.frame = CGRectMake(0, y, toVC.view.frame.size.width, toVC.view.frame.size.height - y);
Let me know if you have found a better solution. I have been struggling with this issue as well and I came up with previous ideas.
I have a Flex 3 app that has elements that a user can add to the main canvas then resize and reposition.
There are 3 key functions I am using for the resize which are as follows:
When the resize begins:
private function startResize(event:MouseEvent):void
{
RESIZE_START_MOUSE_X = event.localX;
RESIZE_START_MOUSE_Y = event.localY;
RESIZE_START_WIDTH = this.width;
RESIZE_START_HEIGHT = this.height;
RESIZE_START_X = this.x;
RESIZE_START_Y = this.y;
RESIZE_BOUND = calculateResizeBound(event);
addEventListener(MouseEvent.MOUSE_MOVE, resizeMouseHandler);
isResizing = true;
}
When the resize is complete:
private function endResize():void
{
RESIZE_START_MOUSE_X = -1;
RESIZE_START_MOUSE_Y = -1;
RESIZE_START_WIDTH = this.width;
RESIZE_START_HEIGHT = this.height;
RESIZE_START_X = -1;
RESIZE_START_Y = -1;
RESIZE_BOUND = '';
removeEventListener(MouseEvent.MOUSE_MOVE, resizeMouseHandler);
isResizing = false;
}
Whilst the user is resizing:
private function resizeMouseHandler(event:MouseEvent):void
{
var deltaX:Number = event.localX - RESIZE_START_MOUSE_X;
var deltaY:Number = event.localY - RESIZE_START_MOUSE_Y;
if (RESIZE_BOUND.indexOf('T') > -1)
//We are fixing the top so move the bottom edge
{
this.height = RESIZE_START_HEIGHT + deltaY;
}
if (RESIZE_BOUND.indexOf('B') > -1)
//We are fixing the bottom so move the top edge
{
this.y = RESIZE_START_Y + deltaY;
this.height = RESIZE_START_HEIGHT - deltaY;
}
if (RESIZE_BOUND.indexOf('L') > -1)
//We are fixing the left so move the right edge
{
this.width = RESIZE_START_WIDTH + deltaX;
}
if (RESIZE_BOUND.indexOf('R') > -1)
//We are fixing the right so move the left edge
{
this.x = RESIZE_START_X + deltaX;
this.width = RESIZE_START_WIDTH - deltaX;
}
}
There is another function referenced in these called calculateResizeBound(). What this does is return a string indicating which edge / corner should remain fixed during the resize. Eg 'TL' means that the top left corner should stay fixed, 'BR' means bottom right, 'L' means just the left edge etc etc
When the resize starts from the 'normal' position, ie the top left corner stays fixed, everything works great. Similarly with the left or top edges fixed. However for the bottom and right cases, I need to reposition the element at the same time as resizing it since all the co-ordinates are calculated from the top left.
The problem that I have is that when it does this, the resize is not smooth, it keeps jumping up and down slightly as you resize it. Not only that but when you resize from the 'normal' edges the cursor position remains fixed relative to the fixed edge / corner however from one of the other edges, you can see it start to drift away from the edge / corner as you resize.
With this kind of thing, it is easy to get the + / - of the different bits of the calculation muddled but since the resize is working in the correct direction each time, I assume I have these correct.
So presumably the problem is coming from the simultaneous moving and resizing but I can't find a work-around for it. Any thoughts / suggestions would be much appreciated
Doug McCune has an awesome Resize wrapper that you can use to resize elements. Then you just need to add a mover on it. See the blog post for code/sample: http://dougmccune.com/blog/2007/08/17/my-360flex-slides-and-code/
I have a VBox containing a bunch of panels. I have implemented dragging and dropping but I need to be able to scroll automatically when the item is drug near the edge. I am having mixed results. I can get it to work, but not well. My example is below. It works if the user bounces their mouse around a little near the top or bottom edge, but I want it to work if they just hold the mouse there. Any suggestions?
On Mouse down (I'm doing several other things but this is one of them):
VBox(di.parent).addEventListener(MouseEvent.MOUSE_MOVE,autoScrollSection,true,500);
On dragDrop
VBox(evt.currentTarget.parent).removeEventListener(MouseEvent.MOUSE_MOVE, autoScrollSection,true);
Here is the autoScroll function:
private function autoScrollSection(evt:MouseEvent):void{
var tempVBox:VBox = VBox(evt.currentTarget);
if(tempVBox.mouseY<50){
tempVBox.verticalScrollPosition += -50;
}
if(tempVBox.mouseY> int(tempVBox.height-50)){
tempVBox.verticalScrollPosition += +50;
}
}
So if they are within 50px of an edge then it should scroll by 50px. I've exaggerated the numbers just to get an affect.
Heres how I solved it:
[Bindable] public var timer:Timer = new Timer(50);
private function autoScrollSection(active:Boolean,cont:VBox):void{
if(active){
timer.addEventListener(TimerEvent.TIMER,function():void{
if(cont.mouseY<50){
cont.verticalScrollPosition += -20;
}
if(cont.mouseY> int(cont.height-50)){
cont.verticalScrollPosition += +20;
}
})
timer.start();
}else{
timer.stop();
}
}
Then changed the calls in mouse down and drag drop to this respectively
autoScrollSection(true,VBox(di.parent));
autoScrollSection(false,VBox(evt.currentTarget.parent));
It works but feels like a bit of a hack. I welcome any better suggestions.
We have this legacy code of a flash video player that functions well enough but still has some loose ends I need to tighten up. It can do the basic "switch to full screen and back to normal size" stunts, however with one exception.
On the first fresh load of the app, if I switch to full screen mode first, and then click to play the movie, the player would be in full screen, yet the movie itself would remain in it's original size.
//trigger
if (stage.displayState == StageDisplayState.NORMAL) {
stage.addEventListener('fullScreen', procFullScreen);
stage.scaleMode = StageScaleMode.NO_SCALE;
stage.displayState = StageDisplayState.FULL_SCREEN;
//mv:VideoDisplay
mv.percentHeight = 100;
mv.percentWidth = 100;
mv.x = 0;
mv.y = 0;
}
// event handler
if (event.fullScreen) {
mv.smoothing = true;
this.height = stage.height;
this.width = stage.width;
//videoCanvas:Canvas
videoCanvas.height = Application.application.height;
videoCanvas.width = Application.application.width;
fullScreenViewStack.selectedIndex = 1;
}
The VideoDisplay object even returns the expected width/height, but the movie just plays in it's original size. If I switch screen sizes during movie playback, then the movie size will shrink or stretch as it should. I'm running out of ideas, any suggestions? Thanks in advance!
Seems like a bug... What version of sdk are you using?
Have you tried calling validateNow() in the VideoDisplay after switching to fullscreen?