I'm creating a slidingView controller using ECSlidingViewController like the one the previous version of Facebook had. Everything works fine but the menuViewController (tableViewController) is being overlapped by the status bar when I add an image to cell like shown below. Does anyone know how to fix it.
it's works 100%
- (void)viewDidLoad
{
if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(#"7.0")) {
[self.tableView setContentInset:UIEdgeInsetsMake(20, self.tableView.contentInset.left, self.tableView.contentInset.bottom, self.tableView.contentInset.right)];
}
[super viewDidLoad];
// Initialize table data
}
Use this to set tableview frame
[self.tableView setFrame:CGRectMake(self.tableView.frame.origin.x, 20, self.tableView.frame.size.width,self.tableView.frame.size.width)];
Related
You can see on the gif below that on the first scroll of UITableView cell's content moves a tiny bit. You can barely see it, margins become 1 pixel wider.I've never encountered this before. It seems like there's some layout issue before the first scroll and it resolves itself after the fact. There's no warning in XCode, these custom cells are pretty straightforward, with no layout code overrides.
I don't know where to start, how do I catch this glitch?
UPDATE. I've implemented an obvious workaround for now:
- (void)scrollTableToFixGlitch {
[self.tableView setContentOffset:CGPointMake(0, 1)];
[self.tableView setContentOffset:CGPointMake(0, -1)];
}
- (void)viewDidLoad {
[super viewDidLoad];
[self scrollTableToFixGlitch];
}
Still looking into the problem. I've tried generic UITableViewCells, nothing changed. Seems like it's the problem with View Controller's root view or tableview layout, and not with the table cells.
UPDATE 2.
I ruled out all the animations out of the question, problem lies somewhere in a different region. The glitch is easy to recreate on a much simplified project. My Tab Bar controller is based on MHCustomTabBarController with custom segues and some other additions. Here's what you do to recreate a glitch. Setup a project where your initial VC is embedded in Navigation Controller. The next controller either MHCustomTabBarController or a subclass is pushed to the navigation stack. First visible VC in tab bar is generic Table View Controller. That's it. Glitch appears only if tab bar controller is pushed in navigation stack.
Here's some code that I think matters from tab bar controller:
-(void) viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
if (self.childViewControllers.count < 1) {
[self performSegueWithIdentifier:#"viewController1" sender:[self.buttons objectAtIndex:0]];
}
}
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if (![segue isKindOfClass:[MHTabBarSegue class]]) {
[super prepareForSegue:segue sender:sender];
return;
}
self.oldViewController = self.destinationViewController;
//if view controller isn't already contained in the viewControllers-Dictionary
if (![self.viewControllersByIdentifier objectForKey:segue.identifier]) {
[self.viewControllersByIdentifier setObject:segue.destinationViewController forKey:segue.identifier];
}
[self.buttons setValue:#NO forKeyPath:#"selected"];
[sender setSelected:YES];
self.selectedIndex = [self.buttons indexOfObject:sender];
self.destinationIdentifier = segue.identifier;
self.destinationViewController = [self.viewControllersByIdentifier objectForKey:self.destinationIdentifier];
[[NSNotificationCenter defaultCenter] postNotificationName:MHCustomTabBarControllerViewControllerChangedNotification object:nil];
}
And a custom segue code:
#implementation MHTabBarSegue
- (void) perform {
MHCustomTabBarController *tabBarViewController = (MHCustomTabBarController *)self.sourceViewController;
UIViewController *destinationViewController = (UIViewController *) tabBarViewController.destinationViewController;
//remove old viewController
if (tabBarViewController.oldViewController) {
[tabBarViewController.oldViewController willMoveToParentViewController:nil];
[tabBarViewController.oldViewController.view removeFromSuperview];
[tabBarViewController.oldViewController removeFromParentViewController];
}
destinationViewController.view.frame = tabBarViewController.container.bounds;
[tabBarViewController addChildViewController:destinationViewController];
[tabBarViewController.container addSubview:destinationViewController.view];
[destinationViewController didMoveToParentViewController:tabBarViewController];
}
#end
UPDATE 3
During my research I've found that - viewWillAppear is not called the first time when child controller appears. But it's called in all subsequent times.
Maybe the scrollviews contentSize is wider than your scrollView's frame(width specifically in this case) causing scrolling for both directions.
You can either try to decrease the contentSize width to the scrollView's width and
self.scrollView.alwaysBounceHorizontal = NO;
If this doesn't work, the solution would be to disable horizontal scrolling programatically by the help of the UIScrollView delegate
self.scrollView.delegate = self;
[self.scrollView setShowsHorizontalScrollIndicator:NO];
//for the below UIScrollView delegate function to work do the necessary step in the bottom of my answer.
-(void)scrollViewDidScroll:(UIScrollView *)scrollView
{
if (scrollView.contentOffset.x > 0)
scrollView.contentOffset = CGPointMake(0, scrollView.contentOffset.y);
}
And in your .h file you should change the interface line to below by adding UIScrollViewDelegate
#interface ViewController : UIViewController <UIScrollViewDelegate>
You most probably know this delegate part very well but for others it might be needed:D
Original answer
Ah, I've finally found the origin of this behaviour. I was almost sure this is happening due to some of the preparation methods are not called properly. As I stated in the update 3 I've found that -viewWillAppear method is not called in TableViewController when my TabBarController is pushed to the navigation stacked. I've found a ton of coverage of this matter on SO, it's a very well known issue apparently.
I've added a simple fix just to check if I'm right in my Custom Segue:
//added this line
[destinationViewController viewWillAppear:YES];
[tabBarViewController.container addSubview:destinationViewController.view];
And it works like a charm, no flickering! Now I have to figure out a more suitable place for this call, since explicit calls to methods like this can break a lot of stuff.
Probably the best place is in -navigationController:willShowViewController:animated: method of UINavigationControllerDelegate.
Anyway, problem solved. Hope it will help someone with the same issue.
UPDATE Actually, I was not completely correct on that. -viewWillAppear is called on my tab bar controller when it's pushed to navigation stack. It's not being translated to TableViewController. So there's no need to access NavigationControllerDelegate. Simple fix to a custom segue is enough.
So, I have a setup as follows:
UITabBarController -> UINavigationController -> UITableViewController
The TabBarController has another view, but that's unimportant. I have the TabBar set to hidden because the user should not be doing the switching between views.
I created a demo project to reproduce the issue with exactly as I described above.
I called
self.tabBarController.tabBar.hidden = YES;
Inside the viewDidLoad method of the tableViewController and was, of course, left with this issue:
So, how did I end up solving hacking my problem?
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
[self.tableView setContentInset:UIEdgeInsetsMake(self.tableView.contentInset.top, self.tableView.contentInset.left, 0, self.tableView.contentInset.right)];
[self.tableView setScrollIndicatorInsets:UIEdgeInsetsMake(self.tableView.contentInset.top, self.tableView.contentInset.left, 0, self.tableView.contentInset.right)];
}
I had to put it inside viewDidAppear because it didn't work in viewDidLoad.
So, does anyone know / can anyone think of a non-hacky way to solve this issue?
Here's a link to the project: https://www.dropbox.com/sh/a6dxecssl3csds7/AAC7xNhSEuawMWCk6hAvyQVYa?dl=0
I am pushing self view to self.navigationcontroller by allocating. I have a tableView on that view so I am changing the content of tableview. But when I am pressing back button (that is automatically created), I am not able to show previous content. Its showing updated content.
Please suggest.
You set code in viewWillAppear method
- (void)viewWillAppear:(BOOL)animated
{
//code set here
}
If you fill the tableView's data in viewWillAppear: or viewDidAppear:, it will reload even if you only press the back button of your top viewController. If you do not want to have your content changed, you are supposed to use initWithNibName: or viewDidLoad: methoads. They are called only at creation time of the view.
Based on the comments on #Kirti's post, You can check if your viewcontroller is being popped by following method, and take some necessary actions for you controller holding table.
-(void) viewWillDisappear:(BOOL)animated
{
if(![self.navigationController.viewControllers containsObject:self])
{
YourControllerWithTable *instance = [self.navigationController.viewControllers objectAtIndex:self.navigationController.viewControllers.count - 1];
instance.loadOldContent = YES;
}
}
In viewWillAppear: of YourControllerWithTable, you can check:
-(void) viewWillAppear:(BOOL)animated
{
if(loadOldContent)
{
//Do your work here
}
}
You don't push UIView instances onto a UINavigationController instance, only instances of UIViewController.
I have a customized tabbar in my app. I want to hide my tabbar when pushing another viewcontroller.
Currently I implemented as this(The original tabbar has been hidden):
myViewController.hidesBottomBarWhenPushed = YES;
((CustomTabBarController *)self.tabBarController).customTabBar.hidden = YES;
[self.navigationController pushViewController:lookBookViewController animated:YES];
But when it is being pushed, it hides my customTabBar immediately. So you can see a black bottom bar in first viewcontroller. Is there a way to fix this problem?
Thanks.
put your these code in - (void)viewDidDisappear:(BOOL)animated;
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
myViewController.hidesBottomBarWhenPushed = YES;
((CustomTabBarController *)self.tabBarController).customTabBar.hidden = YES;
}
you can design like this
and then you need not to hide the tabbar , if you want to hide it , you can use my above code , I think if you design like this , the hide effect will be you want
I have a view with a custom bar at the bottom of the screen. When a collection view cell is pressed, it loads a detail view, and I can go back.
This all works great; however, I have a plus button displayed on the custom bar, and I would like for the plus button to disappear only when the detail view shows up, and then come back when you hit the back button.
So far I have used the delegate method:
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
// Your code to update the parent view
}
The problem is this fires when the detail view is loaded and popped as well. Any idea on how to accomplish this? Thanks!
I assume mainView and detailView are viewControllers. In mainView's viewWillAppear method
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
//get reference of plus button here
btnPlus.hidden = NO;
}
In detailView's viewWillAppear method
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
//get reference of plus button here
btnPlus.hidden = YES;
}