I have a tableview with external delegate controller. Despite content table view array is well populated, and numberOfSectionsInTableView: and
-tableView: numberOfRowsInSection: are called, but-tableView: cellForRowAtIndexPath: is not called.
Issued table view is set in that ways:
CompeticionViewController.h
....
#property (retain, nonatomic) IBOutlet UITableView *calendarioTable;
#property (strong, nonatomic) calendarioViewController *calendarioController;
....
calendarioTable = [[UITableView alloc] init];
calendarioController = [[calendarioViewController alloc] init];
[calendarioTable setDelegate:calendarioController];
[calendarioTable setDataSource:calendarioController];
calendarioController.calendarioArray = [[NSMutableArray alloc] init];
[calendarioController.calendarioArray addObjectsFromArray: self.calendarioarray];
[calendarioTable reloadData];
EDITED:
calendarioViewController.m
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [calendarioArray count];
}
Many thanks
In .xib file link delegate and datasource with File's owner or write
tableview.delegate=self
tableview.datasource=self;
You have used IBOulet for tableview then why are u allocating it as its not need memory already allocated.
Now check in xib of your view controller that tableview is binded and its delegate and datasource provided to file owner.
-----------------------------------------OR------------------------------------------------
add this line in viewDidLoad method
yourtableview.delegate=self
yourtableview.datasource=self;
Now After using IBOulet for tableview you will have bind it with file owner and ViewController interface implements both the <UITableViewDelegate> and <UITableViewDataSource> protocols
Now check array you are providing to tableview has content in it
Edit : Add OR code and done formatting
Be sure that your CompeticionViewController interface implements both the <UITableViewDelegate> and <UITableViewDataSource> protocols.
Related
File: ContactsViewController.m
In this file I am using the didSelectRowAtIndexPath method to push a new View Controller to show information about the name that was pressed on the Table View Controller. The View Controller that will be displaying the information about the name is being implemented in Swift. The part that I am referring to in this code is in the didSelectRowAtIndexPath method, line:
_myIndex = indexPath.row;
I believe indexPath.row should return the index of the name that was tapped in the Table View Controller.
#import "ContactsViewController.h"
#import "Contacts-Swift.h"
#interface ContactsViewController ()
#property (nonatomic, readwrite, strong) NSMutableArray* contacts;
#property (nonatomic, readwrite) NSInteger myIndex;
#end
#implementation ContactsViewController
-(id)initWithCoder:(NSCoder *)aDecoder {
self = [super initWithCoder:aDecoder];
if (self) {
/*NSArray *contactArray = #[#"Johnny Appleseed", #"Paul Bunyan", #"Calamity Jane"];
_contacts = [NSMutableArray arrayWithArray:contactArray];*/
/*Contact *c1 = [[Contact alloc] initWithName: #"Johnny"];
Contact *c2 = [[Contact alloc] initWithName: #"Paul Bunyan"];
Contact *c3 = [[Contact alloc] initWithName: #"Calamity Jane"];*/
// _contacts = [NSMutableArray arrayWithArray: #[c1, c2, c3]];
self.contacts = [NSMutableArray array];
}
return self;
}
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
[self.tableView registerClass: [UITableViewCell class]
forCellReuseIdentifier:#"UITableViewCell"];
}
- (NSInteger)tableView:(UITableView *)tableView
numberOfRowsInSection:(NSInteger)section
{
return self.contacts.count;
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"UITableViewCell" forIndexPath:indexPath];
Contact *contact = self.contacts[indexPath.row];
cell.textLabel.text = contact.name;
return cell;
}
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
ContactsViewController *viewController = [self.navigationController.storyboard instantiateViewControllerWithIdentifier:#"the"];
[self.navigationController pushViewController:viewController animated:YES];
_myIndex = indexPath.row;
}
File: ContactsViewController.h
This is the header file that I am using in order to have access to the objective C methods and variables when working in the swift file. (I am not very familiar with objective C so there is a strong possibility that this implementation is what is causing my problems).
#import <UIKit/UIKit.h>
#interface ContactsViewController : UITableViewController <UITableViewDelegate>
#property (nonatomic, readonly) NSInteger myIndex;
#property (nonatomic, readonly, strong) NSMutableArray* contacts;
#end
File: ExistingContactViewController.swift
In the ExistingContactViewController I am just trying to set the firstName label equal to the text that is present in the contacts array at indexPath.row (in the ContactsViewController.m file).
import UIKit
#objc class ExistingContactViewController: UIViewController {
var contactsObject = ContactsViewController()
#IBOutlet weak var firstName: UILabel!
#IBOutlet weak var lastName: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
print("\(contactsObject.myIndex)")
firstName.text = contactsObject.contacts[contactsObject.myIndex] as? String
}
When clicking names that are added to the Table View Controller the only index that is ever printed
print("\(contactsObject.myIndex)")
is 0. Which tells me that I am not capturing the index of the name that is tapped.
Image of myStoryboard The bottom most scene is the one that I am trying to change the First Name label to display the name of the cell that was tapped.
I have not yet been able change the title of this label when clicking on a cell. I have been able to implement this functionality when using just swift files (through watching numerous videos). I am sure that there is a key concept I am missing in the objective C files so any suggestions and/or pointers are much appreciated. If any additional details are needed let me know!
Thanks.
Seems that in your didSelectRowAtIndexPath: you are pushing a ContactsViewController to the navigation stack and if I understand correctly it should be instance of ExistingContactViewController. Also you should set the contactsObject property of the ExistingContactViewController before pushing it in the navigation stack (before viewDidLoad is executed) otherwise it's value will always be a new ContactsViewController which, probably, is causing the issue.
I hope this helps!
In the viewDidLoad in my UITableView I am calling:
[self registerNib:[UINib nibWithNibName:#"MyCell" bundle:nil] forCellReuseIdentifier:#"MyCellRI"];
Then in the cellForRowAtIndexPath I have the following:
MyCell *cell = [tableView dequeueReusableCellWithIdentifier:#"MyCellRI"];
[cell setup:[items objectAtIndex:indexPath.row]];
Inside the setup method I have a look on [self subviews] to go through the subviews and assign content based on key/value but in this loop I find UITableViewCellContentView's but I do not see the my custom view defined in the NIB.
In the NIB I have assigned Files Owner & The custom class of my cell. The cell is showing I just can't find the NIB view in the subviews.
Please advise.
James
Iterating through subviews is hard work) Try to avoid it. it is not very good practice because it is not reliable. For instance if you decided to change your custom cell UI you will have to change method where you're iterating through subviews.
Try to do following:
Let's say that there is custom cell with UIImage and 3 strings (e.g. person's name, age and cell phone number)
Implement 3 functions in your custom cell to set this values as follows:
MyCustomCell.h
... .h file standart code and then at the end ...
#propert(nonatomic, strong) IBOutlet UIImageView *myImage;
#propert(nonatomic, strong) IBOutlet UILabel *myFirstLabel;
#propert(nonatomic, strong) IBOutlet UILabel *mySecondLabel;
#propert(nonatomic, strong) IBOutlet UILabel *myThirdLabel;
- (void)setUIimage:(UIImage *)_image;
- (void)setFirstString:(NSString *)_string;
- (void)setSecondString:(NSString *)_string;
- (void)setThirdString:(NSString *)_string;
MyCustomCell.m:
#synthesize myImageView, myFirstLabel, mySecondLabel, myThirdLabel;
- (void)setUIimage:(UIImage *)_image {
self.myImageView.image = _image;
}
- (void)setFirstString:(NSString *)_string {
self.myFirstLabel.text = _string;
}
- (void)setSecondString:(NSString *)_string {
self.mySecondLabel.text = _string;
}
- (void)setThirdString:(NSString *)_string {
self.myThirdLabel.text = _string;
}
and finaly in your tableView controller cellForRowAtIndexPath
[myCustomCell setUiImage:someImage];
[myCustomCell setFirstString:oneString];
[myCustomCell setSecondString:twoString];
[myCustomCell setThirdString:threeString];
Hope this approach will help you. Feel free to ask if you have some questions
I'm trying to create a couple of small, static tableviews and add them to a panel that I have which slides in and out. The panel is created programmatically so I can't lay the tableviews out inside it via storyboard, and anyway I'm not sure if this is possible anyhow: It seems the only way you can lay out static tableviews that work is in a tableviewcontroller, which takes up the whole screen.
If you can't tell I'm pretty new to iOS dev so if I'm not understanding some fundamental concepts here please feel free to explain.
Of course is possible. Here is how it can be done:
Drag a TableViewController to your storyboard.
Set its Size to Freeform, add an identifier and uncheck Resize View From NIB
Select the tableview and set its content to Static Cells. Design your cells.
Set its size
Now, wherever you need to instantiate it do it like this:
// I am using a UITableViewController as an example here
// you probably would like to set your actual controller subclass instead
UITableViewController *tableViewController = [[UIStoryboard storyboardWithName:#"MainStoryboard" bundle:[NSBundle mainBundle]] instantiateViewControllerWithIdentifier:#"staticTv"];
UITableView *tableView = tableViewController.tableView;
[self.view addSubview:tableView]; // Or add it to whatever view
Enjoy :)
A UITableViewController isn't necessary to provide the functionality you need to manage a UITableView. I think what you're looking for is the "Delegate" pattern. Any UIViewController can be assigned to be the delegate of the UITableView. For example, I have a "static" table that shows some options in an app I am working on:
#interface LBOptionsViewController : UIViewController <UITableViewDataSource,
UITableViewDelegate>
If you're creating your table views programmatically, you'll probably either be creating them in viewDidLoad or loadView (if you're creating the actual view yourself). After you've created your tableView, assign the delegates:
self.tableView.delegate = self;
self.tableView.dataSource = self;
Then your UIViewController subclass will receive the data delegate messages like:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
Not sure if this helps you. I have not played with Storyboards much yet.
EDIT: #Alladinian has the right answer! If you're using an property for the view controller make sure you allocate it if you need it to be called by other methods.
I've yet to find a usefully reason to use static table view cells over dynamic. Table views were pretty scary when I started iOS programming. I used sqlite in my first app YIKES.
So yeah, you should just import the UITableView Data Source and Delegate and follow up by adding the table view to your panel (assuming it's a uiview and you can add the table view as a subview).
Anyways in your ViewController.h include UITableViewDataSource and UITableViewDelegate.
#interface ViewController : UIViewController<UITableViewDataSource,UITableViewDelegate>
Next, add properties for a UITableView and an NSMutableArray:
#property (strong, nonatomic) UITableView* tableView;
#property (strong, nonatomic) NSMutableArray* tableViewContents;
In your ViewController's .m:
#synthesize tableView;
#synthesize tableViewContents;
inside ViewDidLoad:
self.tableViewContents = [NSMutableArray arrayWithObjects:#"Cell 1",#"Cell 2",#"Cell 3",nil];
[self.tableView setDelegate:self]
[self.tableView setDatasource:self]
In the .m file:
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return self.tableViewContents.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSUInteger row = [indexPath row];
index = row;
static NSString *cellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier] autorelease];
}
cell.textLabel.text = [tableViewContents objectAtIndex:row];
return cell;
}
I try adding objects to NSMutableArray from another class (secondViewController) and then add it to my UITableView in my FirstViewController, but it returns null when I print it using NSLog. Here is my set up.
FirstViewController.h:
#interface FirstViewController : UIViewController <UITableViewDelegate,UITableViewDataSource>{
IBOutlet UITableView *mytableview;
NSMutableArray *mytableinfo;
}
#property (nonatomic,retain) IBOutlet UITableView *mytableview;
#property (retain) IBOutlet NSMutableArray *mytableinfo;
FirstViewController.m
#import "FirstViewController.h"
#import "SecondViewController.h"
#synthesize mytableinfo,mytableview;
-(IBAction)addShift:(id)sender{
SecondViewController *secondViewController = [[SecondViewController alloc]init];
[self presentModalViewController:secondViewController animated:YES];
}
- (void)viewDidLoad
{
mytableinfo = [[NSMutableArray alloc]init];
[super viewDidLoad];
}
SecondViewController.m
#import "SecondViewController.h"
#import "FirstViewController.h"
#implementation SecondViewController
#synthesize dateformatter,mydatepicker,startingTime;
-(IBAction)saveShift:(id)sender{
FirstViewController *firstViewController = [[FirstViewController alloc]init];
[firstViewController.mytableinfo addObject:#"Hello world"];
NSLog(#"%#",firstViewController.mytableinfo);
[self dismissModalViewControllerAnimated:YES];
}
My goal is to ultimately feed a mytableviewfrom mytableinfo. I'm not even sure if this is the best way to go about it. Any advice would be appreciated.
In SecondViewController, you are creating a FirstViewController with alloc init. At that point, mytableinfo on FirstViewController is nil because you don't allocate until viewDidLoad.
What loads SecondViewController? Because you're dismissing it modally. If it's FirstViewController, then when you alloc init first view controller, you're not calling the instance that presented it modally.
It's also not very MVC to have one view poke at another like that. It creates code that's couple at the view layer and modifying data at the view layer. It is better to create a model and have both views modifying that model.
How to create a NSMutable Array which can access from different view controllers
Another way to communicate between views is for one view to pass a delegate (a callback) to the other view. That allows the other view to not be coupled to the other view - it only knows about the protocol for the delegate.
What exactly does delegate do in xcode ios project?
There is a point that look strange to me in your "SecondViewController" you dissmiss it like it's a modal.
My Question is then... who started the modal presentation?
A "FirstViewController"? If it's the case, why are you creating a new one, on dismissing the second, the First that launched it will resume it's activity.
An other thing that I don't understand is that the designated initializer for a UIViewController is
- (id)initWithNibName:(NSString *)nibName bundle:(NSBundle *)nibBundle
You can pass nil to both argument, if no nib need to be associated with.
And finaly, if you need to get back a NSMutableArray to a 1st ViewController (VC) from a 2nd VC that was modally presented by the 1st you can do this in the 2nd VC:
- (id)initWithMutableArray:(NSMutableArray *)theArray {
//... put standard init code here }
And make that the default initializer of your second VC. But this make sense only if 2nd VC absolutely need a mutable array.
And now for my curiosity because I don't understand this line
#property (retain) IBOutlet NSMutableArray *mytableinfo;
Why is this an IBOutlet? That look like a potential source of problem.
IBOutlet are usually pointers to UI elements in a xib file.
When populating a UITableView with an array that can be modified by multiple modal views during the course of your app, I find one of the best ways to do this is with NSUserDefaults. You can create an NSUserDefaults object for reference like this:
NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
Then you can assign objects to each key in defaults, which is really just a plist (which is just a list of keys with objects associated with them.
So then, when you want to store the array in defaults, you can say:
[defaults setObject:mytableinfo forKey:#"tableInformationKey"];
Then, whenever you want to access that data, you can say:
NSMutableArray* tableInfoCopy = [defaults mutableArrayValueForKey:#"tableInformationKey"];
That will make you a copy of the array you have stored in NSUserDefaults (NSUserDefaults can be accessed from anywhere in your app), so then you can make changes to that mutable array you just made. Once you are done making changes, you can reassign it to NSUserDefaults like this:
[defaults setObject:tableInfoCopy forKey#"tableInformationKey"];
So when you populate your UITableView, in
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
put something like:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Foobar"];
if (cell == nil) {
// No cell to reuse => create a new one
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:#"Foobar"] autorelease];
// Initialize cell with some customization
cell.selectionStyle = UITableViewCellSelectionStyleBlue;
cell.textLabel.textColor = [UIColor blackColor];
}
NSArray* arrayOne = [defaults objectForKey:#"tableInformationKey"];
NSString* title = [arrayTwo objectAtIndex:indexPath.row];
//this goes to the index in the array of whatever cell you are
// at, which will populate your table view with the contents of this array (assuming the array contains strings)
// Customize cell
cell.textLabel.font = [UIFont fontWithName:#"Helvetica" size:25];
return cell;
}
Use them the easiest way is to put the array in your AppDelegate
// populate appDelegate's array
AppDelegate *appDelegate = (myAppDelegate *) [[UIApplication sharedApplication] delegate];
[appDelegate.arrayMyTableInfo addObject:#"HelloWorld"];
Here is how you can do what I've suggested :
(This is part of your code updated)
This is in your secondView, this is one of many way to pass the array to your second view.
#synthesize array4Test;
- (id)initWithMutableArray:aMutableArray
{
self = [self initWithNibName:nil bundle:nil];
if (self)
{
self.array4Test = aMutableArray;
}
return self;
}
- (void)dealloc
{
// HERE clean up the property is set to retain.
self.array4Test = nil;
[super dealloc];
}
Here is the code for the firstView
-(IBAction)addShift:(id)sender{
SecondViewController *secondViewController = [[SecondViewController alloc] initWithMutableArray:self.mytableinfo];
[self presentModalViewController:secondViewController animated:YES];
}
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
[self.mytableview reloadData];
NSString *aString = [mytableinfo lastObject];
if (aString)
{
NSLog(#"This just came back from the second View\n%#", aString);
}
}
Hi I have a tab tab controller and my first tab includes a view with:
3 text fields
a submit button
a tableView
Once I fill in the text fields I click submit and it adds the information to my managedObjectContext which is an sqlite database (CoreData).
As soon as I click submit I want the tableView to reload to include the added object. Currently my tableView will display the data in the database but it will only add the new row when I stop and re-run the simulator
This is the code for when the add button is tapped, it is here that I can't get the reload tableView working because it says tableView is an undeclared identifier, what have i missed?
-(IBAction)addButtonTapped:(id)sender {
NSLog (#"Add Button Tapped");
NSLog(#"Adding %# units of item code %# at $%# each",quantityTextField.text,productTextField.text,priceTextField.text);
Products_MarketAppDelegate* delegate = [[UIApplication sharedApplication] delegate];
NSManagedObjectContext* managedObjectContext = delegate.managedObjectContext;
NSManagedObject* newProduct;
newProduct = [NSEntityDescription insertNewObjectForEntityForName:#"Product" inManagedObjectContext:managedObjectContext];
[newProduct setValue:productTextField.text forKey:#"itemCode"];
[newProduct setValue:quantityTextField.text forKey:#"quantity"];
[newProduct setValue:priceTextField.text forKey:#"price"];
if ([managedObjectContext hasChanges])
NSLog(#"Managed Object Changed");
NSError* error;
[managedObjectContext save:&error];
// Insert Reload Table Code Here
// ** I have tried the following and it gives an error "Use of undeclared identifier 'tableView'"
//[tableView reloadData];
//[self.tableView reloadData];
}
As you can see below I have added the UITableViewDelegate & UITableViewDataSource in the header file. I have also hooked up the tableview in IB so that the delegate and datasource connections are linked to file's owner.
#import <UIKit/UIKit.h>
#import <CoreData/CoreData.h>
#interface FirstViewController : UIViewController
<UIApplicationDelegate, UITableViewDataSource,UITableViewDelegate,NSFetchedResultsControllerDelegate>
{
IBOutlet UITextField *productTextField;
IBOutlet UITextField *quantityTextField;
IBOutlet UITextField *priceTextField;
NSMutableArray *items;
NSFetchedResultsController *fetchedResultsController;
}
#property (nonatomic, retain) NSMutableArray *items;
#property (nonatomic, retain) NSFetchedResultsController *fetchedResultsController;
-(IBAction)addButtonTapped:(id)sender;
#end
This is the code to fill the tableView which works correctly
#pragma mark TableView
-(NSInteger)numberOfSectionsInTableView: (UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
id <NSFetchedResultsSectionInfo> sectionInfo = [[fetchedResultsController sections] objectAtIndex:section];
return [sectionInfo numberOfObjects];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil){
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
}
// Configure the cell
Product* productItem =[fetchedResultsController objectAtIndexPath:indexPath];
cell.textLabel.text = [NSString stringWithFormat:#"%# x %# # $%#",productItem.quantity,productItem.itemCode,productItem.price];
return cell;
}
I have searched for answers on this site and on others but I must be doing something different and the solutions aren't helping me
Your UIViewController does not currently have an instance variable pointing to your tableview. Set one up:
#property (nonatomic, retain) IBOutlet UITableView *myTableView;
Remember to synthesize this in your .m
#synthesize myTableView;
Then in your code you can call
[self.myTableView reloadData];
You might have got confused by looking at code examples that use a UITableViewController instead of a UIViewController. The UITableViewController already has an instance variable called tableView, so your subclass wouldn't need it's own tableView instance variable declared. But you're using a UIViewController, so you must declare a tableView instance variable.
Thanks #MattyG for all your help. At first I wasn't sure if I was going against the norm and thats why it wasn't working.
I ended up solving the problem due to your suggestions & it works perfectly! I used the debugger and found that that although we had created a property for the table I had not created an IBOutlet and linked it in my nib file with:
IBOutlet UITableView *myTableView;
I guess this meant that I was telling myTableView to reload but it wasn't hooked up to my table and thus couldn't use the datasource methods.