How would I go about reloading a view controller's table view after the page curl on another view controller is closed.
I have a tableview on viewController1 with a transistion using a page curl to viewController2.
viewController1 has a tableView that needs to be reloaded after the page curl is closed.
thanks for any help
Ok,
in your viewControllers1 register a notification in viewDidLoad:
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(handleNotification:) name:#"MyNotification" object:nil];
and add the method:
- (void)handleNotification:(NSNotification*)note {
[tableView reloadData];
}
in your viewController2 post the notification when you will go to viewController1 or when ever you want to reload the table:
[[NSNotificationCenter defaultCenter] postNotificationName:#"MyNotification" object:self];
In viewController1's viewWillAppear method, you can call the table view's reloadData method.
In viewController1's
- (void)viewDidDisappear:(BOOL)animated
{
[tableView reloadData];
}
tableView has to be a member.
In first viewcontoller.h put this in viewdidload
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(handle_data) name:#"reload_data" object:nil];
-(void)handle_data
{
[yourtableview reloaddata];
}
In second viewcontroller.h
[[NSNotificationCenter defaultCenter] postNotificationName:#"reload_data" object:self];
Related
I am posting a notification locally in the app when ever I receive a remote notification.
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
{
NSLog(#"Received notification: %#", userInfo);
[[NSNotificationCenter defaultCenter] postNotificationName:#"NEWMESSAGE" object:nil userInfo:userInfo]; }
I have added an observer to the view in the function viewWillAppear() and remove the observer in viewWillDisappear().
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(newMessageReceived:) name:#"NEWMESSAGE" object:nil];
and
[[NSNotificationCenter defaultCenter] removeObserver:self];
My question is I want to override every viewWillAppear and viewWillDisappear functions in all *.m files that use these functions in my app.
or how can I dynamically add an observer (like above) to the present view and remove the observer when that view disappears. it should be like a global action whenever view changes observer to be added and removed when it changes again.
Is this possible? if so please guide me.
thanks in advance.
Some thoughts:
You can subclass UIViewController and implement these method in the subclass-ed view controller class. Then you need to create all your views as the subclass of this UIViewController.
Example:
//Creating a custom subclass of UIViewController
#interface CustomViewController : UIViewController
#end
#implementation CustomViewController
- (void)viewWillAppear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(newMessageReceived:) name:#"NEWMESSAGE" object:nil];
}
- (void)viewWillDisappear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
#end
And create all your view controller as the subclass of CustomViewController.
I have a modalViewController that comes up over the top of a viewController with a tableView. When the user clicks a button on the modalViewController I want to reload the tableView within the viewController with this:
[tableView1 reloadData];
I do not want to put the reload in the viewDidAppear or viewWillAppear methods as they get called when i do not need the tableView to reload (i.e. when the user clicks the back button to return to the tableView).
Is there a way to do this?
Try
1) write one method which reloads the table data.
2) Call it on the back button clicked.
This is the classic delegate pattern problem, in your modal view controller you need a delegate reference to the current view controller presenting it
//Modal
#protocol ModalVCDelegate
- (void)tappedBackButton;
#end
#class ModalVC: UIViewController
#property id<ModalVCDelegate> delegate;
#end
#implementation
- (void)backButtonTapped:(id)sender
{
if (self.delegate)
[self.delegate tappedBackButton];
}
#end
Now, in your presenting VC, just process this delegate message
//Parent VC
- (void)showModal
{
ModalVC *vc = [ModalVC new];
vc.delegate = self;
//push
}
- (void)tappedBackButton
{
[self.tableView reloadData];
//close modal
}
You can use delegate . If find it more harder then alternative is to use NSNotificationCenter. You can see accepted answer for Refreshing TableView. This is really very short, easy and understandable way.
using Notification like bellow Method:-
Create NSNotificationCenter at yourViewController's ViewdidLoad Mehod
- (void)viewDidLoad
{
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(ReloadDataFunction:)
name:#"refresh"
object:nil];
[super viewDidLoad];
}
-(void)ReloadDataFunction:(NSNotification *)notification {
[yourTableView reloadData];
}
Now you can Call this Notification from your modelViewController BackButton or else you want from calling this Refresh notification like putting this line of code:-
[[NSNotificationCenter defaultCenter] postNotificationName:#"refresh" object:self];
NOTE: postNotificationName:#"refresh" this is a key of particular Notification
Try to use this one
Make a Button and click on this button and than you can reload your data.
This button make custom and use it on background.
- (IBAction)reloadData:(id)sender
{
[tblView reloadData];
}
You can use NSNotification to refresh table on ViewController.
Inside viewController :
-(void)dealloc{
[[NSNotificationCenter defaultCenter] removeObserver:self];
[super dealloc];
}
Write code in viewDidLoad:
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(reloadMainTable:)
name:#"ReloadTable"
object:nil];
- (void) reloadMainTable:(NSNotification *) notification
{
[tableView reload];
}
Inside ModelViewController:
[[NSNotificationCenter defaultCenter]
postNotificationName:#"ReloadTable"
object:nil];
Here you can also send custom object instead of nil parameter. But be care full about removal of NSNotification observer.
I have a table view with a data source/delegate in another file. In addition, there is a search bar above the table view that belongs to the first file. In other to hide the keyboard when scrolling, I would need to call:
[self.searchBar resignFirstResponder]
But the
(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
method is in the delegate. So how would I hide the keyboard when scrolling in this case?
Thanks!
you could send a notification in scrollviewwillbegindragging. tableview delegate:
-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{
[[NSNotificationCenter defaultCenter] postNotificationName:#"resign" object:nil];
}
searchbar delegate:
-(void)viewDidLoad{
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(goTo:) name:#"resign" object:nil];
}
-(void)goTo:(NSNotification*)notification {
[self.searchBar resignFirstResponder];
}
There are many ways to do,a couple of them are below.
option 1:
add below line after initializing your table object
[yourTableView setKeyboardDismissMode:UIScrollViewKeyboardDismissModeOnDrag];
or
option 2:
Get your tableview's superview(i'm expecting that as aViewcontrollerObj.view) and forcibly end its editing .
-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
UIView *tableviewSuperView = yourTableView.superview;
[tableviewSuperView endEditing:true];
}
Hope that helps
Happy coding :)
i need to dismiss my uiimagepicker modal viewcontroller automatically when the application enters the background.i tried to put the code to dismissmodalviewcontroller code in viewdiddissappear method,but its not being called.so i made a reference to the viewcontroller in appdelegate and tried to put it in the applicationdidenterbackgroundmethod but still it is not working.can someone point out the right way to do this
Try to add an NSNotificationCenter observer for UIApplicationDidEnterBackgroundNotification in the UIViewController that you want to dismiss. Use the selector to dismiss the modalview
- (void)viewWillAppear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] addObserver: self
selector: #selector(didEnterBackground:)
name:UIApplicationDidEnterBackgroundNotification
object:nil];
}
- (void)viewWillDisappear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] removeObserver: self
name:UIApplicationDidEnterBackgroundNotification
object:nil];
}
- (void)didEnterBackground:(NSNotification*)note
{
[self.navigationController dismissModalViewAnimated:NO];
}
Best way to remove the modal when app is moving to background and it works fine .
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(dismissView:)
name:UIApplicationDidEnterBackgroundNotification object:nil];
}
- (void)dismissView:(id)sender {
[self dismissModalViewControllerAnimated:YES];
}
- (void)dealloc {
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
Also you can remove observer like this
[[NSNotificationCenter defaultCenter] removeObserver: self
name:UIApplicationDidEnterBackgroundNotification
object:nil];
I don't think you need to go through all that.
From the docs:
If you present several modal view controllers in succession, and thus build a stack of modal view controllers, calling this method on a view controller lower in the stack dismisses its immediate child view controller and all view controllers above that child on the stack.
Try calling [self dismissModalViewController:NO] from the parent view controller in your implementation of - (void) viewDidUnload.
This is untested, but the docs imply that it should do the job for you.
I would like my UITableView to reloadData once my app is active again, after a user exits the application. I know I need to implement (in my app delegate):
- (void)applicationDidBecomeActive:(UIApplication *)application
but im not sure how to reference the current UITableView?
UPDATE:
My UITableView is a separate controller. It is actually presented as follows
AppDelegate > Root View Controller > Pushes UITabBarController modally which has a UITableViewController
following up on Ole's answer above
add this when initializing the viewcontroller
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(becomeActive:)
name:UIApplicationDidBecomeActiveNotification
object:nil];
add the actual method in the controller
- (void)becomeActive:(NSNotification *)notification {
NSLog(#"becoming active");
}
be sure to clean up the notification
- (void)dealloc {
[[NSNotificationCenter defaultCenter] removeObserver:self];
[super dealloc];
}
If you can't access your view controller from the app delegate, you could also have your controller listen to the UIApplicationDidBecomeActiveNotification notification.
you can create your class called TableViewManager. in there register list of UITableView so that you can refresh any table you want.
it's like this, in yourTableViewManager class, you have a method called
- (void)RefreshTableView:(UITableView *)tableView {
if(tableView != nil)
[tableView reloadData]; }