Hi i am very new in iPhone/iPad developmet.
In my application on clicking of button in want to show view controller like presentModalViewController and i am able to do that which contains the UITableView with some numbers of values. on selecting particulate row i want to pass values to controller which is behind that controller.
for that i am using apple sample application PhotoPicker code. http://developer.apple.com/library/ios/#samplecode/PhotoPicker/Introduction/Intro.html
But i am not able to understand the what i did wrong in my code.
I am not able to go in the code which is in the MyViewController.m
- (void)didFinishWithCamera
{
[self dismissModalViewControllerAnimated:YES];
//Here is my some logic
}
can any one help me for this...how to call this function from OverlayViewController?
please refer above link and guide me or give me some steps or guide me for the same.
use delegation.
I use something like this in a app I'm writing at the moment:
// MySecretSelectionViewController.m
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:YES];
[delegate mySecretSelectionViewController:self didSelectObject:[self objectForIndexPath:indexPath] atIndexPath:indexPath];
}
// MyViewController.m
- (void)mySecretSelectionViewController:(MySecretSelectionViewController *)es didSelectObject:(MySecretObject *)object atIndexPath:(NSIndexPath *)indexPath {
// do something with the selected object
[self dismissModalViewControllerAnimated:YES];
}
- (void)showMySecretSelectionViewController:(id)sender {
MySecretSelectionViewController *vc = ...
vc.delegate = self;
// present ViewController
}
You can also do this with use of NSNotificationCenter.
Inside MyViewController.m:
- (void)viewDidLoad
{
// your code
// Add observers
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(didFinishWithCamera) name:#"YourObserverName" object:nil];
}
+ (void)callDidFinishWithCamera
{
[[NSNotificationCenter defaultCenter] postNotificationName:#"YourObserverName" object:nil];
}
- (void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
// your code
}
From OverlayViewController.m:
[MyViewController callDidFinishWithCamera];
Use the above class method to call didFinishWithCamera in MyViewController from OverlayViewController
Related
I have a view controller, when it's dissming with completion, I post a notfication, and in a subview which contained in another view controller, has added as a oberserve. But, when it tries to execute post notificaiton methode, exec_bad_access happend. what's wrong? The codes are:
BrandListByIdViewController.m
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NSNumber *bid = self.brands[indexPath.row][#"id"];
[self dismissViewControllerAnimated:YES completion:^{
[[NSNotificationCenter defaultCenter] postNotificationName:#"SelectedBrandId" object:nil];
}];
}
SearchNewProduct.h
#interface SearchNewProduct : UIView
#end
SearchNewProduct.m
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(didSelectedBrandId::) name:#"SelectedBrandId" object:nil];
}
}
- (void)didSelectedBrandId:(NSNotification *)notif{
NSLog(#"%s", __PRETTY_FUNCTION__);
}
Even I get rid of the userInfo, still bad access. I created a similar situation in another new project, it works fine.
I didn't realize that you were dealing with a UIView and not a UIViewController (should have read your question better). I think what is happening is that the View is receiving notifications even after being released. Make sure to call dealloc in your UIView and remove itself as an observer:
- (void)dealloc {
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
Also, put an NSLog in that UIView's initWithFrame method to see if it is being called more than once.
This question is very similar:
ios notifications to "dead" objects
Not sure if this is the reason, but when you add your view to the notification center, your selector is wrong:
selector:#selector(didSelectedBrandId::)
There should only be one colon. The entire line should be:
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(didSelectedBrandId:) name:#"SelectedBrandId" object:nil];
Two colons indicates the method takes two arguments, but it only takes one.
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.
- (void)application:(UIApplication *)app didReceiveLocalNotification:(UILocalNotification *)notif {
// Handle the notificaton when the app is running
NSLog(#"Recieved Notification %#",notif);
NSLog(#"local notifications count = %d", [[[UIApplication sharedApplication] scheduledLocalNotifications] count]);
}
This is the method from app delegate, and I need to reload the table view when a notification arrives.
How can I implement the reloadData, since Xcode won't accept if I write "[TableViewController.tableView reloadData];"?
//Just do one thing, as you got the notification , post on more notification as follows in the method ....
- (void)application:(UIApplication *)app didReceiveLocalNotification:(UILocalNotification *)notif {
[[NSNotificationCenter defaultCenter] postNotificationName:#"RELOAD_DATA"object:nil];
}
//the add observer in viewDidLoad of that view controller where your table is added..
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(receiveTableNotification:)
name:#"RELOAD_DATA"
object:nil];
//and make a method in the same class
- (void)receiveTableNotification:(NSNotification *)pNotification{
[your_table_view reloadData];
}
//now remove obser in dealloc in your view controller class where you add observer ..
- (void) dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
[super dealloc];
}
instead of TableViewController.tableView use [self.viewController.tableView reloadData];
If your current view Controller is not the tableView, consider using NSNotificationCenter to post a reload notification
use NSNotificationCenter postNotification: mechanism for posting a reloadTable notification which you can catch in your class having tableViewController by observer to fire reloadData for your tableview
Please call this in app deligate within the call backfunction
- (void)application:(UIApplication *)app didReceiveLocalNotification:(UILocalNotification *)notif {
UINavigationController *navControl = [[[self tableViewController] viewControllers] objectAtIndex:lastObject]; //
id Obj = [[navControl viewControllers] lastObject];
if([Obj isKindOfClass:[Required class]])
{
[Obj reloadDataOfTable];// made an function to desired class.
}
}
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]; }
I want to do a series of things in reaction to the end of certain UITableView animations. For example, I want the table view cell to highlight (via selectRowAtIndexPath) after it has been scrolled to via scrollToRowAtIndexPath.
How can this be done?
Basic template:
[UIView animateWithDuration:0.2 animations:^{
//do some animations, call them with animated:NO
} completion:^(BOOL finished){
//Do something after animations finished
}];
Example: Scroll to row 100. When finished, get the cell at this row and make the cell content view with tag=1 to the firstResponder:
[UIView animateWithDuration:0.2 animations:^{
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:100 inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:NO];
} completion:^(BOOL finished){
//Do something after scrollToRowAtIndexPath finished, e.g.:
UITableViewCell *nextCell = [self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:100 inSection:0]];
[[nextCell.contentView viewWithTag:1] becomeFirstResponder];
}];
I realize this an old post but I was having a similar problem and created a solution that worked well for me. I applied the techniques used on NSCookBook for creating UIAlertViews with blocks. The reason I went for this was because I wanted to use the built-in animations rather than UIView's + animateWithDuration:animations:completion:. There is a larger difference between these animations with the change to iOS 7.
You create a category for UITableView and in the implementation file you create an inner private class that will callback the block by assigning it as your tableview's delegate. The catch is that until the block is called, the original delegate will be "lost" so to speak, since the new delegate is the object that will call the block. That is why I put a notification to send a message when the block has been called to reassign the original UITableViewDelegate. This code has been tested and is working on my end.
// Header file
#interface UITableView (ScrollDelegateBlock)
-(void)scrollToRowAtIndexPath:(NSIndexPath *)indexPath
atScrollPosition:(UITableViewScrollPosition)scrollPosition
animated:(BOOL)animated
scrollFinished:(void (^)())scrollFinished;
#end
// Implementation file
#import "UITableView+ScrollDelegateBlock.h"
#import <objc/runtime.h>
NSString *const BLOCK_CALLED_NOTIFICATION = #"BlockCalled";
#interface ScrollDelegateWrapper : NSObject <UITableViewDelegate>
#property (copy) void(^scrollFinishedBlock)();
#end
#implementation ScrollDelegateWrapper
-(void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView {
if (self.scrollFinishedBlock) {
[[NSNotificationCenter defaultCenter] postNotificationName:BLOCK_CALLED_NOTIFICATION object:nil];
self.scrollFinishedBlock();
}
}
#end
static const char kScrollDelegateWrapper;
static id<UITableViewDelegate>previousDelegate;
#implementation UITableView (ScrollDelegateBlock)
-(void)scrollToRowAtIndexPath:(NSIndexPath *)indexPath
atScrollPosition:(UITableViewScrollPosition)scrollPosition
animated:(BOOL)animated
scrollFinished:(void (^)())scrollFinished {
previousDelegate = self.delegate;
ScrollDelegateWrapper *scrollDelegateWrapper = [[ScrollDelegateWrapper alloc] init];
scrollDelegateWrapper.scrollFinishedBlock = scrollFinished;
self.delegate = scrollDelegateWrapper;
objc_setAssociatedObject(self, &kScrollDelegateWrapper, scrollDelegateWrapper, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
[self scrollToRowAtIndexPath:indexPath atScrollPosition:scrollPosition animated:animated];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(blockCalled:)
name:BLOCK_CALLED_NOTIFICATION
object:nil];
}
/*
* Assigns delegate back to the original delegate
*/
-(void) blockCalled:(NSNotification *)notification {
self.delegate = previousDelegate;
[[NSNotificationCenter defaultCenter] removeObserver:self
name:BLOCK_CALLED_NOTIFICATION
object:nil];
}
#end
You can then call the method like any other with a block:
[self.tableView scrollToRowAtIndexPath:self.currentPath
atScrollPosition:UITableViewScrollPositionMiddle
animated:YES
scrollFinished:^{
NSLog(#"scrollFinished");
}
];
Well if you want to perform an action once the scrollToRowAtIndexPath has been fired.
- (void)scrollToRowAtIndexPath:(NSIndexPath *)indexPath atScrollPosition:(UITableViewScrollPosition)scrollPosition animated:(BOOL)animated
You need to create a CAAnimation pointer like
CAAnimation *myAnimation;
Then set the delgate to self
myAnimation.delegate = self;
Once you do that, these following delegate methods should activate where you can put your code:
- (void)animationDidStart:(CAAnimation *)theAnimation
- (void)animationDidStop:(CAAnimation *)theAnimation finished:(BOOL)flag