Constraint change animation not working on iOS7 - ios

I'm animating the change of an NSLayoutContraint to slide in a view from the top edge of the screen. I already found answers how to do this properly and it works perfectly fine in iOS8. However if I try the same code on iOS7 it just doesn't slide in my view but the view just stays at the same place instead.
Here's my code:
[self.view layoutIfNeeded];
if (_filterVisible) {
[_filterViewTopConstraint setConstant:-_filterViewHeight.constant];
_filterVisible = NO;
}else{
[_filterViewTopConstraint setConstant:0];
_filterVisible = YES;
}
[UIView animateWithDuration:0.5 animations:^{
[self.view layoutIfNeeded];
}];
The constants for the layout constraints have the right values, I already checked that.
Has anybody experienced a similar issue or can help me with this?

Related

prevent to view appear with animmation

I have a problem that my custom navigation bar appears for the first time with animation. I think it happens because I use auto-layout and it animates it self into the state of landscape or portrait. But I want to have a functionality, that after first time I enter the screen everything is still, and where it belongs. and after that if I turn the screen or if I do something all the animations appears like now.
Is there a good think to omit the first animations when the view creates itself?
The animations are : labels floating from left to right. and 1 label appears as from 0px width and height it scales into 100% width and height
code:
[self.navigationController.navigationBar addSubview:self.topBar];
self.topbar is UIView. I have added it to block [UIView performWithoutAnimation:^{ }]; but it does not helps, everytime the view appears for the first time I have my labels floating from left to right.
The answer is that I used some methods [self layoutIfNeeded]; After setting the constraint. The solution is to have a method set like this:
- (void) yourAnimation:(BOOL)animated{
if(animated){
[UIView animateWithDuration:0.3 animations:^{
//your animated code
//[self layoutIfNeeded];
}];
}else{
[UIView performWithoutAnimation:^{
//your stuff without animation
}];
}
}

UIView animateWithDuration... not working in iOS 8

I have a problem with [UIView animationWithDuration] when trying to animate a button when the keyboard come up. I have a notification tell me when the keyboard comes up then I have the ViewController call this method in the view. The button animates but not correctly. It just animates from a random position on the screen to the position it was at previously. The reason I bring this up again is because I've seen answers from other posts saying that setting the view's translatesAutoresizingMaskIntoConstraints property to YES in the ViewController will fix the problem, but it doesn't fix the problem.
[self.view setTranslatesAutoresizingMaskIntoConstraints:YES];
The animation is below:
- (void)animateForKeyboardAppearanceWithKeyboardSize:(CGSize)keyboardSize; {
[UIView animateWithDuration:0.3f
animations:^{
[self.sendSMSButton setFrame:CGRectMake(0,
self.frame.size.height - keyboardSize.height - self.sendSMSButton.frame.size.height,
self.frame.size.width,
self.sendSMSButton.frame.size.height)];
}];
}
Anyone know what's happening? Thanks in advance.
Have you ensured that this method isn't being called repeatedly? Also try subclassing the button, override -setFrame and double check to see if something else is setting the frame of your button while you are trying to animate it.

Hidding view with table scroll

I'm searching for idea how to implement a table view with moving view on top of it.
So the idea is something similar to navBar in facebook app. When you scroll up this (red) view is moving up and hiding, when you scroll up its going up and when you scroll down its revealed. This is not nav bar so most of the pods I've found are not working in this situation. This cannot be tableView header or section header as well.
You need added this view above table:
[self.tableView.superview insertSubview:view aboveSubview:self.tableView]
Or you can do it in storyboard.
When you table scroll down hide view, when up show.
[view setHidden:YES];
Also u could change table inset to the top of the superview.
self.tableView.contentInset = self.tableView.scrollIndicatorInsets = UIEdgeInsetsMake(self.tableView.contentInset.top -, self.tableView.contentInset.left, self.tableView.contentInset.bottom, self.tableView.contentInset.right);
I think fast way to do it use gesture recognizers to recognize reveal and hide actions and than you can use methods like below,
[UIView animateWithDuration:0.5 animations:^{
[attachedView setAlpha:0.0f];
} completion:^(BOOL finished) {
[attachedView setHidden:YES];
}];
and for reveal attached view
[UIView animateWithDuration:0.5 animations:^{
[attachedView setAlpha:1.0f];
} completion:^(BOOL finished) {
[attachedView setHidden:YES];
}];
methods will help you to hide and reveal views gently.
Take a look at this library, it does exactly what you want to do
https://github.com/telly/TLYShyNavBar

How to Use Autolayout to Animate Resizing a UITextView's Bottom Constraint When Content Has Been Scrolled

Background
I'm working on a quick and dirty notes app purely to try to understand autolayout. As such I am looking for an autolayout-specific solution to this problem.
I am quite sure that my terminology and understanding of this subject may be incorrect in places so if I misphrase or omit information through ignorance that would otherwise be helpful I am very happy to update this question with better specifics.
Short Problem Summary
This app is a simple note app. On the detail view of the note, there are two text input views, a UITextField, and a UITextView.
The goal is to use autolayout to animate a change of height to the UITextView when it is being edited (making room for the keyboard), and then animate the UITextView back to it's original size when editing is finished.
The animation code I have in place works, however when the UITextView is scrolled near to the bottom of the text the animation from "editing" size to "non-editing" size displays incorrectly durring the animation. (The final result of the animation, however is correct.)
I'm open to alternate "correct" ways of doing this if there's a common pattern for the solution. I am, however, looking for an autolayout solution which, I believe, means avoiding modifying the view's frame directly. (Could be wrong on that.)
Details and Code
A short video of the problem is available here:
http://pile.cliffpruitt.com/m/constraint_problem.mp4
This is the code performing the animation:
// self.bodyFieldConstraintBottom refers to an outlet referencing the UITextView's bottom constraint
// This animation occurrs when the text view is tapped
- (BOOL)textViewShouldBeginEditing:(UITextView *)textView
{
[self enterEditingMode];
[UIView animateWithDuration:2.35
animations:^{
NSLayoutConstraint *bottom_constraint = self.bodyFieldConstraintBottom;
bottom_constraint.constant = 216;
[self.view layoutIfNeeded];
}];
return YES;
}
// This animation occurrs when editing ends and the text field size is restored
- (BOOL)textViewShouldEndEditing:(UITextView *)textView
{
[self exitEditingMode];
[UIView animateWithDuration:2.35
animations:^{
NSLayoutConstraint *bottom_constraint = self.bodyFieldConstraintBottom;
bottom_constraint.constant = 20;
[self.view layoutIfNeeded];
}];
return YES;
}
Full project source (in all it's messy glory) can be downloaded here:
http://pile.cliffpruitt.com/dl/LittleNotebooks.zip
Additional Comments
My understanding of cocoa terminology isn't the best so I'm having a hard time making google searches and docs searches effective. My best guess about the problem (based on observing the animation at a slow speed) is that it is related to a scroll offset somehow because unless the text is scrolled past a certain point, the problem does not manifest itself.
I have read quite a few SO question/answers including:
Resizing an UITextView when the keyboard pops up with auto layout
How to resize UITextView on iOS when a keyboard appears?
UIScrollView animation of height and contentOffset "jumps" content from bottom
The problem is that these answers either do not work ([self.bodyField setContentInset:UIEdgeInsetsMake(0, 0, 216, 0)]; seems to have no effect) or appear to rely on setting the frame of the UIText view which I believe is not supposed to be done when using autolayout.
Final Side Note
I've been at this off and on for about 4 days so my understanding and recollection of all I've read and tried is actually a little less clear than when I'd started. I hope I'm explaining this well enough to convey the issue.
EDIT:
I've noticed that this code actually gets somewhat close to the desired result:
- (BOOL)textViewShouldBeginEditing:(UITextView *)textView
{
[self enterEditingMode];
[UIView animateWithDuration:2.35
animations:^{
[self.bodyField setContentInset:UIEdgeInsetsMake(0, 0, 216, 0)];
[self.view layoutIfNeeded];
}];
return YES;
}
- (BOOL)textViewShouldEndEditing:(UITextView *)textView
{
[self exitEditingMode];
[UIView animateWithDuration:2.35
animations:^{
[self.bodyField setContentInset:UIEdgeInsetsMake(0, 0, 0, 0)];
[self.view layoutIfNeeded];
}];
return YES;
}
The problem with this version is that the scroll indicator scrolls down past the visible area of the text content, meaning it gets "lost" behind the keybaord. Also, it does not help me understand the correct way to animate a UITextView (UIScrollView ?) bottom constraint.
The issue looks weird and I am really not sure whats the main issue but I found out that for the best results you should call [self.view setNeedsUpdateConstraints]; before animating view.
My example code to animate view when keyboard appears:
-(void)keyboardWillShow:(NSNotification *)notification {
CGSize kbSize = [notification.userInfo[UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
//BH: iOS7 is messed up
CGFloat keyboardHeight = kbSize.width;
if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(#"8.0")) {
keyboardHeight = kbSize.height;
}
self.centerYConstraint.constant = keyboardHeight;
[self.view setNeedsUpdateConstraints];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:[notification.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
[UIView setAnimationCurve:[notification.userInfo[UIKeyboardAnimationCurveUserInfoKey] integerValue]];
[UIView setAnimationBeginsFromCurrentState:YES];
[self.view layoutIfNeeded];
[UIView commitAnimations];
}
I am using commit animations to animate view with same animationCurve as iOS is animating keyboard so view is moving 1 to 1 accordingly to keyboard. Also, please notice if statement for iOS8 vs iOS7 where Apple finally fixed window sizing.

Auto Layout constraint change does not animate

I was learning the auto layout with animations from the tutorial
http://weblog.invasivecode.com/post/42362079291/auto-layout-and-core-animation-auto-layout-was
and things were working perfect.
When I tried to use this concept in my application, trying to animate a settings screen(a UIView) from bottom to top,it works great when the settings screen is just an empty UIView,
But in case I add a UILabel as a subview to this settings screen, the animation just vanishes.
On removing this UILabel form the settings screen, the animation is visible.
Here are the outlets that I have connected
__weak IBOutlet UIView *settingsView;
__weak IBOutlet NSLayoutConstraint *settingsBottomConstraint;
__weak IBOutlet NSLayoutConstraint *settingsViewHeightConstraint;
View did load setup method(setupViews)
-(void)setupViews
{
settingsBottomConstraint.constant = - settingsViewHeightConstraint.constant;
[settingsView setNeedsUpdateConstraints];
[settingsView layoutIfNeeded];
isSettingsHidden = YES;
}
Hide/Unhide Method
- (IBAction)showSettingsScreen:(id)sender {
if (isSettingsHidden) {
settingsBottomConstraint.constant = 0;
[settingsView setNeedsUpdateConstraints];
[UIView animateWithDuration:.3 animations:^{
[settingsView layoutIfNeeded];
}];
}
else{
settingsBottomConstraint.constant = - settingsViewHeightConstraint.constant;
[settingsView setNeedsUpdateConstraints];
[UIView animateWithDuration:0.3 animations:^{
[settingsView layoutIfNeeded];
}];
}
isSettingsHidden = !isSettingsHidden;
}
My issue seems similar to the
Issue with UIView Auto Layout Animation
I found the answer.
Instead of,
[settingsView layoutIfNeeded];
this line made it worked like charm,
[self.view layoutIfNeeded];
I suppose we need to perform layoutIfNeeded method on the parent view not just the view we are trying to animate.
UPDATE:
As pointed out in a comment by codyko, this is required for iOS 7, iOS 10.
For iOS 8 this issue does not exists.

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