Object property set to null - ios

Can someone please see where I am going wrong with this?
I have a object called Object with a single NSString property.
I then have a MainViewController with a button on it. The button is created programatically and added at runtime.
When yo click this button, it is supposed to set the value of the Object proper to a String, and pass this to the next ViewController.
I manage to set the value of the Object property, but when I call that value to pass it, it is set to null. I have tried many different solutions but nothing seems to work. Can anyone see where my problem lies? I have added all the relevant code below
Object.h
#interface Object : NSObject
#property (nonatomic, strong) NSString *content;
Object.m
#import "Object.h"
#implementation Object
#synthesize content;
Then in MianViewController I create the button and set value of Object property
MainViewController.h
#interface MainViewController : UIViewController
#property (nonatomic, strong) UIButton *myButton;
MainViewController.m
#import "MainViewController.h"
#import "SecondaryViewController.h"
#import "Object.h"
.
.
#synthesize myButton;
- (void)viewDidLoad
{
[super viewDidLoad];
myButton = [UIButton buttonWithType:UIButtonTypeCustom];
myButton.tag = 1;
myButton.frame = CGRectMake(20, 140, 280.f, 40.f);
UIImage *airButton = [UIImage imageNamed:#"gettingHereByAirButton.png"];
[myButton setBackgroundImage:airButton forState:UIControlStateNormal];
[self.view addSubview:myButton];
[myButton addTarget:self action:#selector(myButtonClicked) forControlEvents:UIControlEventTouchUpInside];
}
- (void) myButtonClicked
{
[self performSegueWithIdentifier:#"mySegue" sender:self];
}
- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
NSLog(#"Getting Here...");
Object *object = [[Object alloc] init];
object.content = #"This is the content of the Object";
NSLog(#"Content of Object Set To: %#", object.content);
SecondaryViewController *vc;
vc.object = object;
NSLog(#"Object: %#", object);
NSLog(#"Object.content: %#", object.content);
NSLog(#"ViewController.object.content: %#", vc.object.content);
NSLog(#"Just Did Stuff...");
}
And the SecondaryViewController where the label should be set to that of the Object String
SecondaryViewController.h
#import "Object.h"
#interface SecondaryViewController : UIViewController
#property (weak, nonatomic) IBOutlet UILabel *contentLabel;
#property (nonatomic, strong) Object *object;
SecondaryViewController.m
#synthesize object;
#synthesize contentLabel;
- (void)viewDidLoad
{
[super viewDidLoad];
NSLog(#"Content of Object: %#", object.content);
self.contentLabel.text = object.content;
}
And finally a screen grab of my NSLog when the app is running HERE

SecondaryViewController *vc;
Should be
SecondaryViewController *vc = (SecondaryViewController *)segue.destinationViewController;

Related

Button values appearing as "null"

I'm trying to have two buttons in my SearchCategoryChooserViewcontroller to display titles based on values being returned by a function. However, the buttons seem to be showing up with "null" for a title, even though the topCategoriesArray is successfully being returned. Here's my setup:
SearchCategoryChooserViewController.m:
#import "SearchCategoryChooserViewController.h"
#import "SearchViewController.h"
#interface SearchCategoryChooserViewController ()
#end
#implementation SearchCategoryChooserViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
UIButton *category1 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
category1.frame = CGRectMake(10, 120, 300, 35);
[category1 setTitle: [NSString stringWithFormat:#"%#", self.topCategory1] forState:UIControlStateNormal];
[category1 addTarget:self action:#selector(myButtonClick:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview: category1];
UIButton *category2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
category2.frame = CGRectMake(10, 180, 300, 35);
[category2 setTitle: [NSString stringWithFormat:#"%#", self.topCategory2] forState:UIControlStateNormal];
[category2 addTarget:self action:#selector(myButtonClick:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview: category2];
// Do any additional setup after loading the view.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
/*
#pragma mark - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
}
*/
#end
SearchCategoryChooserViewController.h:
#import <UIKit/UIKit.h>
#import "SearchViewController.h"
#interface SearchCategoryChooserViewController : SearchViewController
#end
SearchViewController.h:
#import <UIKit/UIKit.h>
#import <Parse/Parse.h>
#import <Parse/PFCloud.h>
#import "CriteriaViewController.h"
#interface SearchViewController : UIViewController
#property (weak, nonatomic) IBOutlet UIButton *nextButtonOutlet;
#property (weak, nonatomic) NSString *topCategory1;
#property (weak, nonatomic) NSString *topCategory2;
#end
SearchViewController.m:
#import "SearchViewController.h"
#interface SearchViewController ()
#property (weak, nonatomic) IBOutlet UITextField *itemSearch;
#property (weak, nonatomic) IBOutlet UIButton *nextButton;
#end
#implementation SearchViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
[self.nextButtonOutlet addTarget:self action:#selector(nextButton:) forControlEvents:UIControlEventTouchUpInside];
// Do any additional setup after loading the view.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)nextButton:(id)sender
{
if (self.itemSearch.text.length > 0) {
[PFCloud callFunctionInBackground:#"eBayCategorySearch"
withParameters:#{#"item": self.itemSearch.text}
block:^(NSDictionary *result, NSError *error) {
NSLog(#"'%#'", result);
NSArray *resultArray = [result objectForKey:#"results"];
NSDictionary *dictionary0 = [resultArray objectAtIndex:0];
NSNumber *numberOfTopCategories = [dictionary0 objectForKey:#"Number of top categories"];
NSDictionary *dictionary1 = [resultArray objectAtIndex:1];
NSNumber *topCategories = [dictionary1 objectForKey:#"Top categories"];
NSDictionary *dictionary2 = [resultArray objectAtIndex:2];
NSNumber *numberOfMatches = [dictionary2 objectForKey:#"Number of matches"];
NSDictionary *dictionary3 = [resultArray objectAtIndex:3];
NSNumber *userCategoriesThatMatchSearch = [dictionary3 objectForKey:#"User categories that match search"];
NSArray *topCategoriesArray = [dictionary1 objectForKey:#"Top categories"];
NSString *topCategory1 = [topCategoriesArray objectAtIndex:0];
NSString *topCategory2 = [topCategoriesArray objectAtIndex:1];
if (!error) {
// if 1 match found clear categoryResults and top2 array
if ([numberOfMatches intValue] == 1 ){
[self performSegueWithIdentifier:#"ShowMatchCenterSegue" sender:self];
}
// if 2 matches found
else if ([numberOfMatches intValue] == 2){
[self performSegueWithIdentifier:#"ShowUserCategoryChooserSegue" sender:self];
//default to selected categories criteria -> send to matchcenter -> clear categoryResults and top2 array
}
// if no matches found, and 1 top category is returned
else if ([numberOfMatches intValue] == 0 && [numberOfTopCategories intValue] == 1) {
[self performSegueWithIdentifier:#"ShowCriteriaSegue" sender:self];
}
// if no matches are found, and 2 top categories are returned
else if ([numberOfMatches intValue] == 0 && [numberOfTopCategories intValue] == 2) {
[self performSegueWithIdentifier:#"ShowSearchCategoryChooserSegue" sender:self];
}
}
}];
}
}
#pragma mark - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// if([segue.identifier isEqualToString:#"ShowSearchCategoryChooserSegue"]){
// SearchCategoryChooserViewController *controller = (SearchCategoryChooserViewController *) segue.destinationViewController;
// controller.itemSearch.text = self.itemSearch.text;
// }
}
#end
There are multiple issues:
You should change the code:
#property (weak, nonatomic) NSString *topCategory1;
#property (weak, nonatomic) NSString *topCategory2;
to
#property (strong, nonatomic, copy) NSString *topCategory1;
#property (strong, nonatomic, copy) NSString *topCategory2;
or
//because strong is default
#property (nonatomic, copy) NSString *topCategory1;
#property (nonatomic, copy) NSString *topCategory2;
It is better if you add the ´copy´ attribute for the NSString properties in case of using NSMutableString value.
Because with ARC if there is not at least one strong reference for an object it will be deallocated. If your Object have only a weak reference to an another object, it is not own it and it will be deallocated even if you use it in your Object. But with strong reference your Object own the another Object and it will not be deallocated until your Object lives.
And you should be set the property values before perform a segue with change this code
NSString *topCategory1 = [topCategoriesArray objectAtIndex:0];
NSString *topCategory2 = [topCategoriesArray objectAtIndex:1];
to
self.topCategory1 = [topCategoriesArray objectAtIndex:0];
self.topCategory2 = [topCategoriesArray objectAtIndex:1];
and use the values in prepareForSegue:
if([segue.identifier isEqualToString:#"ShowSearchCategoryChooserSegue"]){
SearchCategoryChooserViewController *controller = (SearchCategoryChooserViewController *) segue.destinationViewController;
controller.itemSearch.text = self.itemSearch.text;
controller.topCategory1 = self.topCategory1;
controller.topCategory2 = self.topCategory1;
}
It appears to me (from the code you've pasted into your question) that you are never setting your "topCategory1" string property in your SearchCategoryChooserViewController object.
Which would explain why you are seeing "null" in the label.

Pass info to multiple viewControllers via iCarousel

I'm trying to implement an iCarousel that will pass information on to two other view controllers when an image is chosen. While the iCarousel loads perfectly and transitions to the next VC, the information is not displayed on the new VC.
The approach I chose was to create an NSObject file. I can't simply pass the info from VC to VC since I have several VC's that need the information and I'd prefer not to create a singleton or use AppDelegate if possible.
FYI: I do have a tap gesture recognizer added on top of the UIView that acts as the segue to the next VC if that makes any difference.
I've tried every possible tutorial out there and can't seem to figure out my problem. I just need to display a text label and a picture, which should really be pretty easy. Can someone take a quick glance at my code to see what I'm doing wrong?
My NSObject File:
#import <Foundation/Foundation.h>
#interface Stop : NSObject
#property (nonatomic, strong) NSString *title;
#property (nonatomic, strong) NSString *image;
#end
First ViewController.h (with iCarousel on it):
#import <UIKit/UIKit.h>
#import <QuartzCore/QuartzCore.h>
#import "iCarousel.h"
#import "DirectionsViewController.h"
#import "Stop.h"
#interface StopsMenuViewController : UIViewController <iCarouselDataSource, iCarouselDelegate>
#property (strong, nonatomic) IBOutlet iCarousel *carousel;
#property (strong, nonatomic) IBOutlet UILabel *titleLabel;
//Title
#property (nonatomic, strong) NSArray *stopTitles;
#property (nonatomic, strong) NSString *stopChosen;
//Image
#property (nonatomic, strong) NSArray *stopImages;
#property (nonatomic, strong) NSString *imageChosen;
#end
First ViewController.m:
#import "StopsMenuViewController.h"
#interface StopsMenuViewController () {
NSMutableArray *allInfo; }
#end
#implementation StopsMenuViewController
#synthesize titleLabel, carousel, stopImages, stopTitles, stopChosen, imageChosen;
- (void)awakeFromNib {
NSString *myPlist = [[NSBundle mainBundle] pathForResource:#"Chinatown" ofType:#"plist"];
NSDictionary *rootDictionary = [[NSDictionary alloc] initWithContentsOfFile:myPlist];
self.stopImages = [rootDictionary objectForKey:#"StopImages"];
self.stopTitles = [rootDictionary objectForKey:#"StopTitles"];
}
- (void)carouselDidScroll:(iCarousel *)carousel {
[titleLabel setText:[NSString stringWithFormat:#"%#", [self.stopTitles
objectAtIndex:self.carousel.currentItemIndex]]];
}
- (void)dealloc {
self.carousel.delegate = nil;
self.carousel.dataSource = nil;
}
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([[segue identifier] isEqualToString:#"toDirections"])
{
DirectionsViewController *dvc = [segue destinationViewController];
int itemId = [self.carousel currentItemIndex];
NSIndexPath *path = [NSIndexPath indexPathForRow:itemId inSection:0];
Stop *current = [allInfo objectAtIndex:path.row];
[dvc setPassInfo:current];
}
}
- (void)viewDidLoad {
[super viewDidLoad];
self.carousel.type = iCarouselTypeCoverFlow2;
allInfo = [[NSMutableArray alloc] init];
Stop *info = [[Stop alloc] init];
stopChosen = [NSString stringWithFormat:#"%#", [self.stopTitles objectAtIndex:self.carousel.currentItemIndex]];
[info setTitle:stopChosen];
[allInfo addObject:info];
info = [[Stop alloc] init];
self.imageChosen = [NSString stringWithFormat:#"%#", [self.stopImages
objectAtIndex:self.carousel.currentItemIndex]];
[info setTitle:self.imageChosen];
[allInfo addObject:info];
}
- (void)viewDidUnload
{
[super viewDidUnload];
self.carousel = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
return YES;
}
- (NSUInteger)numberOfItemsInCarousel:(iCarousel *)carousel {
return [self.stopImages count];
}
- (NSUInteger)numberOfVisibleItemsInCarousel:(iCarousel *)carousel {
return 4;
}
- (UIView *)carousel:(iCarousel *)_carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView *)view {
if (view == nil)
{
view = [[UIImageView alloc] initWithImage:[UIImage imageNamed:[self.stopImages objectAtIndex:index]]];
}
return view;
}
- (void)carousel:(iCarousel *)carousel didSelectItemAtIndex:(NSInteger)index {
DirectionsViewController *dvc = [self.storyboard instantiateViewControllerWithIdentifier:#"dvc"];
[self.navigationController pushViewController:dvc animated:YES];
}
#end
Second ViewController.h:
#import <UIKit/UIKit.h>
#import "Stop.h"
#interface DirectionsViewController : UIViewController
#property (strong, nonatomic) IBOutlet UILabel *titleLabel;
#property (strong, nonatomic) IBOutlet UIImageView *imageBox;
#property (nonatomic, strong) Stop *PassInfo;
#property (nonatomic, strong) NSString *stopTitle;
#property (nonatomic, strong) NSString *myStopTitle;
#end
Second ViewController.m:
#import "DirectionsViewController.h"
#interface DirectionsViewController ()
#end
#implementation DirectionsViewController
#synthesize PassInfo;
- (void)viewDidLoad {
[super viewDidLoad];
[self.titleLabel setText:[PassInfo title]];
UIImage *image = [UIImage imageNamed:[PassInfo image]];
[self.imageBox setImage:image];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
#end
Instead of
- (void)carousel:(iCarousel *)carousel didSelectItemAtIndex:(NSInteger)index {
DirectionsViewController *dvc = [self.storyboard instantiateViewControllerWithIdentifier:#"dvc"];
[self.navigationController pushViewController:dvc animated:YES];
}
Use
- (void)carousel:(iCarousel *)carousel didSelectItemAtIndex:(NSInteger)index {
[self performSegueWithIdentifier:#"toDirections" sender:self];
}
In your code, you're instantiating the second view controller and presenting it, which is not the same as performing a segue. Therefore the method - prepareForSegue:sender: will not be invoked.

Add a push segue to a button inside of a custom cell of a tableview

I have a project that displays a feed of statuses similar to other social networks. Each feed item has several button that do different things. 1 of the buttons opens a new viewcontroller that displays the comments that have been posted on a particular status. When this button is clicked and the view controller is opened i would like it to be a push segue so that their is a back button and the user can navigate back to the feed.
When this button is clicked and the new vc is launched some unique data about the particular status/cell being clicked needs to be sent to the "comments vc ". Where would the code for doing this go?
CUSTOM CELL .H
#import <UIKit/UIKit.h>
#interface FeedItemCell : UITableViewCell
#property (weak, nonatomic) IBOutlet UIImageView *DefaultImg;
#property (weak, nonatomic) IBOutlet UILabel *NameLabel;
#property (weak, nonatomic) IBOutlet UILabel *StatusLabel;
#property (weak, nonatomic) IBOutlet UILabel *timeLabel;
#property (nonatomic, copy) NSString *msg_id;
#property (nonatomic, copy) NSString *status;
#property (nonatomic, weak) IBOutlet UIButton* commentButton;
#property (nonatomic, weak) IBOutlet UIButton* bumpButton;
#property (strong, nonatomic) id delegate;
-(IBAction)viewComments:(id)sender;
-(IBAction)bump:(id)sender;
#end
#protocol CustomCellProtocol <NSObject>
- (void)EBCellPressed:(NSString *)cellName;
CUSTOM CELL .M
#import "FeedItemCell.h"
#import "CommentsViewController.h"
#import "NSDate+TimeAgo.h"
#interface FeedItemCell() <WYPopoverControllerDelegate>
{
}
- (IBAction)open:(id)sender;
- (void)close:(id)sender;
#end
#implementation FeedItemCell
#synthesize commentButton;
- (instancetype)initWithDelegate:(id)delegate {
self = [super init];
if (self) {
self.delegate = delegate;
// Initialization code
}
return self;
}
-(IBAction)bump:(id)sender{
[self.delegate EBCellPressed:#"NAME"];
}
- (IBAction)open:(id)sender
{
}
#end
publicFeed . M
#import "PublicFeedViewController.h"
#import "FeedItemCell.h"
#import "AFNetworking.h"
#import "UIImageView+WebCache.h"
#import "InboxDetailViewController.h"
#import "SWRevealViewController.h"
#import "CommentsViewController.h"
#import "NSDate+TimeAgo.h"
#interface PublicFeedViewController (){
NSArray *NameLabel;
NSArray *StatusLabel;
NSMutableArray *feedArray;
}
#end
#implementation PublicFeedViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
//The below code prompts the user for push notifications. If allowed, code in AppDelegate takes over and stores the token.
[[UIApplication sharedApplication] registerForRemoteNotificationTypes:(UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeSound | UIRemoteNotificationTypeAlert)];
// Do any additional setup after loading the view.
self.FeedTable.dataSource=self;
self.FeedTable.delegate=self;
// Set the side bar button action. When it's tapped, it'll show up the sidebar.
_sidebarButton.target = self.revealViewController;
_sidebarButton.action = #selector(revealToggle:);
// Set the gesture
[self.view addGestureRecognizer:self.revealViewController.panGestureRecognizer];
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
NSDictionary *parameters = #{#"foo": #"bar"};
[UIApplication sharedApplication].networkActivityIndicatorVisible = TRUE;
[manager POST:#"www" parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {
//NSLog(#"JSON: %#", responseObject);
self->feedArray = [responseObject objectForKey:#"feed"];
[self.FeedTable reloadData];
[UIApplication sharedApplication].networkActivityIndicatorVisible = FALSE;
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
return 1;
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return feedArray.count;
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSString *CellIdentifier=#"Cell";
FeedItemCell *Cell=[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if(!Cell){
Cell = [[FeedItemCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
NSLog(#"FEED ARRAY: %#", self->feedArray);
NSDictionary *tempDictionary= [self->feedArray objectAtIndex:indexPath.row];
// Display recipe in the table cell
NSString *thumb_img = [tempDictionary objectForKey:#"thumb_img"];
NSString *thumb_path=#"http://buhzhyve.com/CI_REST_LOGIN/UPLOADS/thumbs/";
NSString *thumb_url = [thumb_path stringByAppendingString:thumb_img];
Cell.NameLabel.text=[tempDictionary objectForKey:#"first_name"];
Cell.StatusLabel.text=[tempDictionary objectForKey:#"message"];
Cell.msg_id=[tempDictionary objectForKey:#"msg_id"];
//Cell.status=[tempDictionary objectForKey:#"message"];
Cell.StatusLabel.lineBreakMode=0;
Cell.StatusLabel.numberOfLines=0;
NSString *commentCount = [tempDictionary objectForKey:#"comment_count"];
NSString *commentButtonText =[NSString stringWithFormat:#"Comments ( %# )",commentCount];
[Cell.commentButton setTitle:commentButtonText forState: UIControlStateNormal];
NSString *bumpCount = [tempDictionary objectForKey:#"bump_count"];
NSString *bumpButtonText =[NSString stringWithFormat:#"Bumps ( %# )",bumpCount];
[Cell.bumpButton setTitle:bumpButtonText forState: UIControlStateNormal];
//[Cell.StatusLabel sizeToFit];
NSString *created_string=[tempDictionary objectForKey:#"created"];
double created_double = created_string.doubleValue;
NSDate *date = [[NSDate alloc] initWithTimeIntervalSince1970:created_double];
NSString *ago = [date timeAgo];
Cell.timeLabel.text=ago;
//Cell.DefaultImg.image = [UIImage imageNamed:#"buhz_mini_logo.png"];
[Cell.DefaultImg setImageWithURL:[NSURL URLWithString:thumb_url]
placeholderImage:[UIImage imageNamed:#"buhz_mini_logo.png"]];
return Cell;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
//Ideally you should do lazy loading so that instead of creating a new textView each time, you just reuse the same one.
UITextView *temp = [[UITextView alloc] initWithFrame:CGRectMake(82, 26, self.FeedTable.frame.size.width, 18)]; //This initial size doesn't matter
NSDictionary *tempDictionary= [self->feedArray objectAtIndex:indexPath.row];
NSString *status = [tempDictionary objectForKey:#"message"];
temp.font =[UIFont fontWithName:#"System" size:12];
temp.text = status;
CGFloat textViewWidth = 218;
CGRect tempFrame = CGRectMake(82,26,textViewWidth,18); //The height of this frame doesn't matter.
CGSize tvsize = [temp sizeThatFits:CGSizeMake(tempFrame.size.width, tempFrame.size.height)]; //This calculates the necessary size so that all the text fits in the necessary width.
//Add the height of the other UI elements inside your cell
return tvsize.height + 70;
}
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:#"commentSegue"]) {
}
}
#end
publicfeed .h
#import <UIKit/UIKit.h>
#interface PublicFeedViewController : UIViewController<UITableViewDataSource,UITableViewDelegate>
#property (weak, nonatomic) IBOutlet UITableView *FeedTable;
#property (weak, nonatomic) IBOutlet UIBarButtonItem *sidebarButton;
- (IBAction)addItem;
#end
So assuming that you're creating this button in code, this is how you could handle this.
This first line tells the button that when it's pressed, it needs to call this specific selector/method sent as the action.
[button addTarget:self action:#selector(showNextViewController) forControlEvents:UIControlEventTouchUpInside];
Then you would create this method in the same class.
- (void) showNextViewController
{
NewViewController *newViewController = [[NewViewController alloc] init]; //Edit this line of course to fit for your situation. I'm not sure if you're loading from an XIB or from a Storyboard, or neither.
newViewController.someVariable = someVariable;
newViewController.someOtherVariable = someOtherVariable;
[[[[[UIApplication sharedApplication] delegate] window] rootViewController].navigationController pushViewController:view animated:YES];
}
This will send the necessary data to the new view controller, and it will also display the new view on the screen with a back button.
Hope this works!
1. Ok so lets pretend this is your custom cell class.
in your .h file of the custom cell you need to add a protocol.
#import <UIKit/UIKit.h>
#interface CustomCell : UIView
#property (strong, nonatomic) id delegate; //this is used for sending messages out of the custom cell
//init
- (id)initWithFrame:(CGRect)frame andCatName:(NSString *)name andDelegate:(id)delegate;
#end
#protocol CustomCellProtocol <NSObject>
-(void)customCellSelected:(NSString *)cellName;
#end
what we actually did is something like creating a custom event that the class can throw out and everyone who subscribes to that can run a method when customCellSelected is thrown.
2. now when you create each custom cell with the init method you need to provide a delegate which kind of points to which class should the custom cell transfer the call to customCellSelected so in the init method you set that delegate.
- (id)initWithFrame:(CGRect)frame andDelegate:(id)delegate {
self = [super initWithFrame:frame];
if (self) {
self.delegate = delegate; //setting which class should be called when calling protocol methods.
// Your initialization code
}
return self;
}
3. now in your .m file of the custom cell, when the user presses your button and you enter your method , let it be buttonPressed
- (IBAction) buttonPressed:(id)sender {
[self.delegate customCellSelected:#"THE CELL'S NAME"]; // calling the protocol method.
}
now the call to the delegate method should be transferred to the vc because when you create the custom cell you use initWithFrame:(CGRect)frame andDelegate:(id)delegate and you transfer self as the delegate , so when [self.delegate customCellSelected:#"THE CELL'S NAME"]; is called it is actually called on the vc.
4. this is how you create the custom cell in the vc:
customCell *tempView = [[customCell alloc] initWithFrame:CGRectMake(X, Y, Width, Height) andDelegate:self]; // here you set the vc as the delegate
5.and now all you have to do is add the method customCellSelected to your vc code so it can called when the customCell is calling it.
- (void)customCellSelected:(NSString *)cellName {
self.selectedCell = cellName;
[self performSegueWithIdentifier:#"SelectedCell" sender:self];
}
6.then add this in the vc:
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:#"SelectedCell"]) {
LevelSelectViewController *levelSelectViewController = (LevelSelectViewController *)segue.destinationViewController;
levelSelectViewController.cellName = self.selectedCell;
}
}
7.only thing you have to remember is to create a segue from your first vc to the second like this:

Performing method on another UIViewController

I am using following code to set the text of a UILabel in SViewController, From another ViewController FViewController
SViewController *vc = [self.storyboard instantiateViewControllerWithIdentifier:#"SViewController"];
[vc setTextForLabel:[NSNumber numberWithInt:1];];
[self.navigationController pushViewController:vc animated:YES];
The setTextForLabel method:
-(void) setTextForLabel: (NSNumber *)text {
textLabel = [[UILabel alloc] init];
[textLabel setText:[NSString stringWithFormat:#"%#",[text stringValue]]];
NSLog(#"The text is %#", textLabel.text);
}
I have declared the property for textLabel in .h file is as follows:
#property (nonatomic, retain) IBOutlet UILabel *textLabel;
And I have also set the IBOutlet in storyboard.
Now in console I see "The text is 1", but the UI is not showing anything!
What am I doing wrong?
remove this line
textLabel = [[UILabel alloc] init];
Also, you need to link the UILabel on interface to your #property (nonatomic, retain) IBOutlet UILabel *textLabel;
Or you may add this label manually to view
textLabel = [[UILabel alloc] init];
[textLabel setText:[NSString stringWithFormat:#"%#",[text stringValue]]];
[self.view addSubView:textLabel];
First of all go put
[vc setTextForLabel:[NSNumber numberWithInt:1]];
after you push the vc.
In your xib/storyboard if your label has something written in it, remove it, leave it blank.
If that doesn't work ... leave the setText method before the push one (as you wrote it initialy) and create a NSNumber member that will hold your value and apply it in viewDidAppear like so
-(void) setTextForLabel: (NSNumber *)text{
numberValue = text; // declared in .h as NSNumber *numberValue (only make it a property if you need acces to it from outside your class)
}
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated]; //this is important
[textLabel setText:[NSString stringWithFormat:#"%#",[numberValue stringValue]]];
}
Your problem is linked to the view lifecycle of SViewController. When you call [.. setTextForLabel] you don't know if the controller has loaded its views (And thus your UILabel have a good chance of not being created yet)
What you should do is use a NSString property on your controller, set it with the desire text and assigned it to the UILabel in the viewDidLoad of SViewController.
in SViewController.h
#propery (strong, nonatomic) NSString *textToDisplay;
in SViewController.m
-(void)viewDidLoad
{
[super viewDidLoad];
// Here you know all Outlet are loaded and connected
textLabel.text = textToDisplay
}
I did like this
#import "FViewController.h"
#import "SViewController.h"
#interface FViewController ()
#end
#implementation FViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (IBAction)do:(id)sender
{
SViewController *vc = [self.storyboard instantiateViewControllerWithIdentifier:#"SViewController"];
[self.navigationController pushViewController:vc animated:YES];
[vc setTextForLabel:[NSNumber numberWithInt:1]];
}
// in SViewController.h
#import <UIKit/UIKit.h>
#interface SViewController : UIViewController
#property (weak, nonatomic) IBOutlet UILabel *label;
-(void) setTextForLabel: (NSNumber *)text;
#end
// SViewController.m file
#import "SViewController.h"
#interface SViewController ()
#end
#implementation SViewController
#synthesize label;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
}
-(void) setTextForLabel: (NSNumber *)text{
// label.text = [text stringValue];
NSLog(#"%#",label);
[label setText:[text stringValue]];
}
#end
also check your label properties in storyboard are properly set

dynamically generated UIButton in iOS 5 ARC causes deallocated instance crash

I have a a class I created to generate UIButton's I add to my UIView. This worked great until my conversion to ARC yesterday, not I get the following error:
-[OrderTypeButton performSelector:withObject:withObject:]: message sent to deallocated instance 0x12449f70
Here is the code to add the button to my UIView (actually a subview in my main UIView):
OrderTypeButton *btn = [[OrderTypeButton alloc]initWithOrderType:#"All Orders" withOrderCount:[NSString stringWithFormat:#"%i",[self.ordersPlacedList count]] hasOpenOrder:NO];
btn.view.tag = 6969;
btn.delegate = self;
[btn.view setFrame:CGRectMake((col * width)+ colspacer, rowHeight + (row * height), frameWidth, frameHeight)];
[self.statsView addSubview:btn.view];
And here is my class header:
#import <UIKit/UIKit.h>
#protocol OrderTypeButtonDelegate
-(void) tapped:(id)sender withOrderType:(NSString*) orderType;
#end
#interface OrderTypeButton : UIViewController {
id<OrderTypeButtonDelegate> __unsafe_unretained delegate;
IBOutlet UILabel *lblOrderType;
IBOutlet UILabel *lblOrderCount;
NSString *orderType;
NSString *orderCount;
BOOL hasOpenOrder;
}
#property (nonatomic, strong) IBOutlet UIButton *orderButton;
#property (nonatomic, strong) IBOutlet UILabel *lblOrderType;
#property (nonatomic, strong) IBOutlet UILabel *lblOrderCount;
#property (nonatomic, strong) NSString *orderType;
#property (nonatomic, strong) NSString *orderCount;
#property (nonatomic, assign) BOOL hasOpenOrder;
#property (nonatomic, unsafe_unretained) id<OrderTypeButtonDelegate> delegate;
-(id) initWithOrderType: (NSString *) anOrderType withOrderCount: (NSString *) anOrderCount hasOpenOrder: (BOOL) openOrder;
-(IBAction)btnTapped:(id)sender;
#end
Implementation:
#import "OrderTypeButton.h"
#implementation OrderTypeButton
#synthesize orderButton;
#synthesize lblOrderType, lblOrderCount, orderType, orderCount, hasOpenOrder, delegate;
-(id) initWithOrderType: (NSString *) anOrderType withOrderCount: (NSString *) anOrderCount hasOpenOrder: (BOOL) openOrder {
if ((self = [super init])) {
self.orderType = anOrderType;
self.orderCount = anOrderCount;
self.hasOpenOrder = openOrder;
}
return self;
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
self.lblOrderType.text =[NSString stringWithFormat:#"%#", self.orderType];
self.lblOrderCount.text = [NSString stringWithFormat:#"%#", self.orderCount];
if (self.hasOpenOrder) {
[self.orderButton setBackgroundImage:[UIImage imageNamed:#"background-order-btn-red.png"] forState:UIControlStateNormal];
self.lblOrderType.textColor = [UIColor whiteColor];
self.lblOrderCount.textColor = [UIColor whiteColor];
}
}
-(IBAction)btnTapped:(id)sender {
NSLog(#"TAPPED");
if ([self delegate] ) {
[delegate tapped:sender withOrderType:self.orderType];
}
}
- (void)viewDidUnload
{
[self setOrderButton:nil];
[super viewDidUnload];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return YES;
}
#end
This seems fairly simple what I am doing here, not sure what changed with ARC that is causing me problems.
Maybe ARC autorelease created button, try to store created buttons in Array
//.h file
#property (nonatomic, strong) NSArray *buttonsArray
//.m file
#synthesize buttonsArray
...
- (void)viewDidLoad {
buttonsArray = [NSArray array];
...
OrderTypeButton *btn = [[OrderTypeButton alloc]initWithOrderType:#"All Orders"
withOrderCount:[NSString stringWithFormat:#"%i",[self.ordersPlacedList count]]
hasOpenOrder:NO];
btn.view.tag = 6969;
btn.delegate = self;
[btn.view setFrame:CGRectMake((col * width)+ colspacer, rowHeight + (row * height), frameWidth, frameHeight)];
[self.statsView addSubview:btn.view];
//Add button to array
[buttonsArray addObject:btn];
Also this approach will help if you want to change buttons, or remove some specific button from view

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