UITableView reloadData doesn't work - ios

I've read all similar questions and tried all suggestions, still nothing. Maybe someone can spot my flaw.
My view controller is initiated from another view controller, by one of two buttons. Button taps send NSNotification (with attached arrays), and this view controller anticipates this notification and then calls this method:
- (void)addContentToArray:(NSNotification *)aNotification {
array = [NSArray arrayWithArray:[aNotification object]];
([array count] == 6) ? (category = YES) : (category = NO);
[myTableView reloadData];
NSLog(#"%d", [array count]);
NSLog(#"%#", myTableView);
}
The method gets called every time, I can see that from changing array count. Here notification object is the array passed from previous view controller, and I assign these objects to my local array property - this is my UITableView source. So what I do is I try to reuse the UITableView to display elements of whatever array is being passed. And it works nicely for the first array passed (whichever first).
When I tap the second button, the new array is passed successfully (as mentioned before, I know that from log of [array count] which is different: 3 vs 6 objects in different arrays). However, what is not happening is that UITableView does not refresh (although the values passed when I select a row in the table are from the correct arrays, even though wrong values are displayed).
Here are UITableView data source methods:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [array count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Identifier"];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:#"Identifier"];
}
cell.textLabel.text = [[array objectAtIndex:indexPath.row] objectForKey:#"name"];
if (category) {
cell.detailTextLabel.text = [[array objectAtIndex:indexPath.row] objectForKey:#"description"];
}
return cell;
}
So, what am I doing wrong?
A few other considerations that might help:
NSLog(#"%#", myTableView); returns (null), which is a bit worrying. myTableView here is UITableView from my nib file, which is correctly connected to the view controller, declared as property and synthesized
The view controller in question is a rightViewController of the PKRevealController, so when it is called repeatedly, viewWillAppear method is called, but not viewDidLoad (although, as I already mentioned, addContentToArray: method is being called every time as well)
Also, for those somewhat familiar with PKRevealController - when I try and log focusedController from my view controller, it says that frontViewController - the one that moves to reveal my view controller - is the one that is focused. Can that be the reason why myTableView is (null)?
I'd be grateful for any insight and help!

Need more code, that part where you created and call Myviewcontroller's addContentToArray method.
I think you used release code there for Myviewcontroller's object, try once with hide that part.

I managed to solve the issue by editing initWithNibName method (old line commented out)
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
//self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
self = [super initWithNibName:#"PurposeCategoryViewController" bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
Apparently, it did have something to do with the fact that my view controller (called PurposeCategoryViewController) was not the top/focused view controller in PKRevealController hierarchy. So, I just needed to specifically indicate my nib file.

What value are you returning in this delegate method:
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
make sure it is 1

Related

Search Bar and Search Display Controller in table view

I have tried to implement a search bar but I have not had any luck dealing with this problem. I would really appreciate any help that can be provided. I've a big project in which I've a table view, and I want to implement a search bar over it and see the real time filtering. I do not use Storyboard but I'm using XIB. I've added the following protocols:
<UITableViewDelegate,UITableViewDataSource,UISearchBarDelegate,UISearchDisplayDelegate>
I've declared 2 arrays in #interface , the first for the whole elements and the second one for the filtered ones:
NSArray* OldList;
NSArray* filteredList;
Then I've setted the number of rows and the number of sections and then:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
myClassCell *cell = [tableView dequeueReusableCellWithIdentifier:MYCELLCLASS];
if (cell == nil)
{
cell = [myClassCell newFromNib];
}
NSMutableDictionary* elem = nil;
if (tableView == self.searchDisplayController.searchResultsTableView)
{
elem = [filteredList objectAtIndex:indexPath.row];
if ([elem count]+1 > indexPath.row)
[cell showValues:elem];
else
[cell showValues:nil];
}
else
{
elem = [OldList objectAtIndex:indexPath.row];
if ([elem count]+1 > indexPath.row)
[cell showValues:elem];
else
[cell showValues:nil];
}
return cell;
}
-(void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope
{
NSPredicate *resultPredicate = [NSPredicate predicateWithFormat:#"name contains[c] %#", searchText];
filteredist = [OldList filteredArrayUsingPredicate:resultPredicate];
}
-(BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString
{
[self filterContentForSearchText:searchString scope:[[self.searchDisplayController.searchBar scopeButtonTitles]
objectAtIndex:[self.searchDisplayController.searchBar selectedScopeButtonIndex]]];
return YES;
}
At this point, I haven't done any changes to the xib, no links and no other stuffs. If I compile I get my table, but obviously if I try to search something, nothing works. Moreover if I scroll down to the end of the table the app crashes. The real problem is that I can't see the search bar working. Could someone help me please?
Well you're on the right track... it is exactly to do with the connection of your controller class to your controller xib.
When you want to initialise a Search Bar and Search Display Controller into a UITableView, you are effectively adding a second table view that, when activated, must be managed by code in your UITableViewController class in the same manner as any UITableView.
I have used these SO questions/answers to check my own answer - I recommend you take a look:
Creating a UISearchDisplayController programmatically
Gray UISearchBar w/matching scope bar programmatically
I have read the Apple Documentation. I recommend you do the same to help you understand this.
First Step:
You will need to set data source and delegate methods for both table views when you run your controller class.
Before you do any of this, include this property...
#property (nonatomic, strong) UISearchDisplayController *searchController;
The following code describes how to initialise and set the appropriate properties for a UISearchBar and a UISearchDisplayController. If you are programmatically creating a UITableViewController in code you will also need to set the data source and delegate for it (not shown to keep the code easy to read).
You have two options here - which one you choose depends on your code and what you wish to achieve - either set these in your init/awakeFromNib methods, or set these in one of your table view controller (TVC) lifecycle methods.
Option One - Init
(Note1: Paul Hegarty's extraordinary iTunesU lectures taught me to init/awake a class as follows - in this way you are covered for both scenarios - you call init or it can awakeFromNib.)
- (void)setup {
// Provide initialisation code here!!!
UISearchBar *searchBar = [[UISearchBar alloc] initWithFrame:CGRectZero];
[searchBar sizeToFit];
[searchBar setDelegate:self];
[self setSearchController:[[UISearchDisplayController alloc] initWithSearchBar:searchBar
contentsController:self]];
[self.searchController setSearchResultsDataSource:self];
[self.searchController setSearchResultsDelegate:self];
[self.searchController setDelegate:self];
}
- (void)awakeFromNib {
[self setup];
}
- (id)initWithStyle:(UITableViewStyle)style {
self = [super initWithStyle:style];
if (self) {
[self setup];
}
return self;
}
OR
Option Two - TVC Lifecycle
- (void)viewDidLoad {
[super viewDidLoad];
UISearchBar *searchBar = [[UISearchBar alloc] initWithFrame:CGRectZero];
[searchBar sizeToFit];
[searchBar setDelegate:self];
[self setSearchController:[[UISearchDisplayController alloc] initWithSearchBar:searchBar
contentsController:self]];
[self.searchController setSearchResultsDataSource:self];
[self.searchController setSearchResultsDelegate:self];
[self.searchController setDelegate:self];
[self.tableView setTableHeaderView:self.searchController.searchBar]; // see Note2
...< other code as required >...
}
Note2: Regardless of which of these options you choose, you will need to place the following line of code in your viewDidLoad method...
[self.tableView setTableHeaderView:self.searchController.searchBar]; // (or just searchBar)
Second Step:
Notes:
The table view that represents your complete data set (OldList) can be called using self.tableView (PS convention is to start each variable with lower case - so change your property name from OldList to oldList).
The table view that represents the filtered data set (filteredList) can be called using self.searchController.searchResultsTableView.
While you have prepared your tableView:cellForRowAtIndexPath: data source method, I suspect you have other data source (and maybe delegate) methods that need to be informed of which table view is the current table view, before they are able to function properly and provide you with a fully operational search results table view and search function.
For example:
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
if (tableView == self.searchController.searchResultsTableView)
return 1;
return [[self.oldList sections] count];;
}
and:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
if (tableView == self.searchController.searchResultsTableView)
return [self.filteredList count];
return [self.oldList count];
}
Note that there may be other data source (and maybe delegate) methods that need to be informed of which table view is the current table view... I will leave it to you to determine which of these methods are to be modified, and the corresponding code necessary to adjust the table view.
Third Step:
You will be required to register a nib and reuse identifier for your search results table view.
I prefer to create a separate nib file (called "TableViewCellSearch.xib") that contains one table view cell, with the reuse identifier "SearchCell", and then place the code to register this nib and reuse identifier in the following UISearchDisplayController delegate method.
It is worth noting that this code is just as effective after the code block examples above in init/awakeFromNib/viewDidLoad.
- (void)searchDisplayController:(UISearchDisplayController *)controller willShowSearchResultsTableView:(UITableView *)tableView {
static NSString *cellIdentifierSearch = #"SearchCell";
UINib *nib = [UINib nibWithNibName:#"TableViewCellSearch" bundle:nil];
[self.searchController.searchResultsTableView registerNib:nib forCellReuseIdentifier:cellIdentifierSearch];
}
Try these suggestions.
Hope this helps.

How to pass the in-place edited content back to the previous tableview controller (update the model)

I have two table views, one called mainTableViewController (mtvc), the other called detailTableViewController (dtvc). It's very typical click the accessory button on the main tableview cell bring you to the detail tableview kinda thing.
In the prepareForSegue method, the data passed from the main tableview to detail tableview is a NSMutableArray called item.
And this is how I got it displayed: cell.detailTextLabel.text = self.item[indexPath.row];
The cool thing is I managed to do in-place editing on the detail table view cell (overwrote the NSTableViewCell, added a UITextField as subview to each cell).
everything works, the last thing I spent whole day cannot figure out is how do I update the NSMutableArray item after in-place editing taken place, the ultimate goal is in-place editing, and the main tableview data shall reflect the change.
I tried to use delegation and protocol but it does not work (the in-place edited content didn't got passed back, part of the reason is I don't know how to capture the edited content, it's not like it's a text field with a name, I can't just do updatedContent = self.myTextField.text to grab the change)
I'm running out of ideas, any help would be highly appreciated, thanks.
Here's the prepareForSegue in the main tableview controller
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([segue.identifier isEqualToString:#"toInventoryDetail"]) {
NSMutableArray *selectedItem = nil;
if (self.searchDisplayController.active) {
selectedItem = _searchResults[[sender row]];
} else {
selectedItem = _appDelegate.items[[sender row]];
}
UPFInventoryDetailTableViewController *idtvc = segue.destinationViewController;
idtvc.item = selectedItem;
}
}
and here's the cellForRowAtIndex at the detail tableview controller
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UPFEditableUITableViewCell *cell = [[UPFEditableUITableViewCell alloc] initWithStyle:UITableViewCellStyleValue2 reuseIdentifier:CellIdentifier];
cell.textLabel.text = _appDelegate.title[indexPath.row];
cell.detailTextLabel.text = self.item[indexPath.row];
[cell showEditingField:YES];
return cell;
}
I wrote the delegation but delete them after cause they didn't work.
I had an idea, still using delegation and protocol obviously: when the 'done' button in the detail tableview hit, I go grab all the row contents and build a new array, using delegation to pass this new array back to the main tableview controller, add this new array into the model meanwhile delete the old one. The tricky thing is still HOW CAN I GRAB ALL THE CONTENTS in the detail tableview?
update:
Haha! I think solved half of the puzzle !
here's the solution for the detail tableview controller
- (IBAction)doneUpdate:(UIBarButtonItem *)sender {
[self.delegate addItem:[self newItem]];
}
- (NSMutableArray *)saveItem
{
NSMutableArray *newItem = [[NSMutableArray alloc] init];
NSArray *indexPathes = [self.tableView indexPathsForVisibleRows];
for (NSIndexPath *indexPath in indexPathes) {
UPFEditableUITableViewCell *cell = (UPFEditableUITableViewCell *)[self.tableView cellForRowAtIndexPath:indexPath];
[newItem addObject:cell.editField.text];
}
return newItem;
}
and here's the main tableview controller
- (void)addItem:(NSArray *)item
{
//take the updated item then insert the items array as new item
[_appDelegate.items addObject:item];
//remove the selected item (the one being updated) from the items array
[_appDelegate.items removeObject:_appDelegate.selectedItem];
[self.tableView reloadData];
[self.navigationController popViewControllerAnimated:YES];
}
When you creating a cell - give tags to your UITextFields
You can collect data entered by its delegate methods - you can either make NSDictionary/ key value pairs or you can add it to NSArray.
- (void)textFieldDidEndEditing:(UITextField *)textField {
if(textField.tag == 11) {
// you can add it to your desired array/dictionary
}
}
OR
- (BOOL)textFieldShouldReturn:(UITextField *)textField {
if(textField.tag == 11) {
// you can add it to your desired array/dictionary
}
}
You can use Delegation/Protocol or store this values in NSUserDefault and get it back on mainViewController.
Do you have a separate data model class(classes) for your selectedItem? That would be the appropriate way to persist data between the two TableViewControllers. It can be Core Data or simply a NSMutableArray that lives in memory. The DetailViewController updates the item and saves the changes, then the mainTableViewController reloads the TableView (or even just the data backing the previously edited cell.
Perhaps even consider the Model-View-Controller-Store pattern promoted by BigNerdRanch.

Fails to call delegate/datasource methods in UITableView implementation

I have created .h and .m files for UITableView called mainTableViewgm.h and mainTableViewgm.m resp. and I am calling -initWithFrame: method from my main view controller to this mainTableViewgm.m implementation file
[[mainTableViewgm alloc]initWithFrame:tableViewOne.frame]
Note that this tableview is in my main view controller. But I have created separate files for the tableView and have also set the custom class to mainTableViewgm in storyboard.
the -initWithFrame: methods appears as follows
- (id)initWithFrame:(CGRect)frame
{
//NSLog(#"kource data");
self = [super initWithFrame:frame];
if (self)
{
[self setDelegate:self];
[self setDataSource:self];
[self tableView:self cellForRowAtIndexPath:0];
[self tableView:self numberOfRowsInSection:1];
// Initialization code
}
return self;
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
NSLog(#"kource data");
return 1;
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSLog(#"kource data2");
UITableViewCell*cellOne =[[UITableViewCell alloc]init];
cellOne.detailTextLabel.text=#"text did appear";
return cellOne;
}
the -initWithFrame: is being called fine along with the 'if (self)' block in this method. But the problem is numberOfRowsInSection: and cellForRowAtIndexPath: are not being automatically called here . kource data/kource data2 never appear in log. What do I do to load the table? Are the delegate/datasource being set incorrectly?
I must mention that I have also set the UITableViewDelegate and UITableviewDataSource protocols:
#interface mainTableViewgm : UITableView <UITableViewDelegate,UITableViewDataSource>
#end
Help will be much appreciated. Thank you.
Your tableview is not loaded when the controller is initializing, so you cannot do that in the init methods. You have to move your code to the viewDidLoad method.
Also you are not setting the delegate and datasource on the tableview object (probably a type, you are setting them on the view controller). It should look like this:
- (void)viewDidLoad:(BOOL)animated {
[super viewDidLoad:animated];
[self.tableView setDelegate:self];
[self.tableView setDataSource:self]; // <- This will trigger the tableview to (re)load it's data
}
Next thing is to implement the UITableViewDataSource methods correctly. UITableViewCell *cellOne =[[UITableViewCell alloc] init]; is not returning a valid cell object. You should use at least initWithStyle:. And take a look how to use dequeueReusableCellWithIdentifier:forIndexPath:. A typical implementation would look like this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
// Reuse/create cell
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// Update cell contents
cell.textLabel.text = #"Your text here";
cell.detailTextLabel.text=#"text did appear";
return cell;
}
I can't believe I've been doing XCode programming for two years, and still hit this issue.
I had the same problem with XCode 6.1 - I was setting my UITableView's delegate & dataSource in the viewWillAppear function, but none of the delegate functions were kicking in.
However, if I right-clicked on the UITableView on the Storyboard, the circles for delegate and dataSource were empty.
The solution, then, is to hold down the CTRL key, and drag from each of these circles up to the name of your UIView which contains your UITableView:
After doing this, my UITableView happily populated itself.
(So, we're upto v6.1 of XCode now are we ? Do you think Apple ever going to make this thing, you know, friendly...? I would quite like to add a Bookmark in my code... that'd be a nice feature.)

ReloadData for UITableView not working; tableView returns NULL when logged

I am calling a method in my TableViewController class from another class.
To call the method of displaying the tableview, I do this:
TableViewController *tableVC = [[TableViewController alloc]init];
[tableVC setTableViewContent];
then in TableViewController.h
#interface TableViewController : UITableViewController <UITableViewDelegate, UITableViewDataSource>
{
NSMutableArray *nameArray;
}
-(void)setTableViewContent;
#property (nonatomic, strong) IBOutlet UITableView *tableView;
#end
TableViewController.m
#implementation TableViewController
#synthesize tableView;
- (void)viewDidLoad
{
nameArray = [[NSMutableArray alloc]init];
[super viewDidLoad];
}
-(void)setTableViewContent{
AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
for(int i=0;i< [appDelegate.businessArray count];i++)
{
NSDictionary *businessDict = [[appDelegate.businessArray objectAtIndex:i] valueForKey:#"location"];
nameArray = [appDelegate.businessArray valueForKey:#"name"];
}
NSLog(#"%#", nameArray);
NSLog(#"tableview: %#", tableView);
// here tableview returns null
[tableView reloadData];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return [nameArray count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSLog(#"updating tableview...");
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell =[tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// Configure the cell...
cell.textLabel.text = [nameArray objectAtIndex:indexPath.row];
return cell;
}
For some reason when I try to log the tableview, it returns null, so the ReloadData doesn't work. The delegate and datasource is connected properly in IB, and there is a referencing outlet for tableView.
Any idea what is going on here? Thanks in advance
If you added the table view controller to a container view, then you can get a reference to that controller in prepareForSegue. For a controller in a container view, prepareForSegue will be called right before the parent controller's viewDidLoad, so you don't need to do anything to invoke it. In my example below, I've called the segue "TableEmbed" -- you need to give the segue that identifier in IB.
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if([segue.identifier isEqualToString:#"TableEmbed"]) {
TableViewController *tableVC = (TableViewController *)segue.destinationViewController;
[tableVC setTableViewContent];
}
}
Be aware that prepareForSegue:sender: is called before either controller's viewDidLoad is called, so you should move the initialization of your array to setTableViewContent, and your reloadTable should go into viewDidLoad.
BTW, it's not clear to me why you want to call setTableContent from your other class anyway. Why not move all the code in that method to the viewDidLoad method of the table view controller?
This is happening because you are calling a method on tableView before it actually exists. Simply initializing that class doesn't draw the table itself, so using reloadData before the table has actually been created doesn't really make any sense.
What you want to do in this situation is create your nameArray in whatever class is calling setTableViewContent, and then pass it in either via a custom init method, or by setting tableVC.nameArray before loading that table view controller.
What I would do is make custom init method like - (id)initWithArray:(NSMutableArray *)nameArr
Which should look something like this:
if (self = [super init]) {
nameArray = [nameArr copy];
}
return self;
Then where you have TableViewController *tableVC = [[TableViewController alloc]init]; put TableViewController *tableVC = [[TableViewController alloc]initWithArray:theNameArray]; where theNameArray is the content in setTableViewContent (which you are now generating in the same class that calls the table view instead of in the table view itself).
Make sense?
I solved a similar situation by creating a "safe" reload method on the UITableViewController:
- (void)reloadTableViewData
{
if ([self isViewLoaded])
[self.tableView reloadData];
}
According to the docs for isViewLoaded:
Calling this method reports whether the view is loaded. Unlike the view property, it does not attempt to load the view if it is not already in memory.
Therefore it is safe to call reloadTableViewData on the table view controller at any time.

Uitableview cell changes value when scrolling

The code below is creating a search for many strings. Initially there are 5 rows, when you reach row five, it adds another row. Instead of just directly editing the row, i load a filter controller (another view controller that as you type it completes words for you). When the user finishes finding a word he clicks it and comes back to this view controller. Now i want to fill the cell that was originally tapped with the text from the filter.
I tried asking earlier and didn't get any concrete answers.
I am running into a problem where when i scroll (after adding a new row), it starts filling in those rows with info already in the table, (as opposed to staying blank)
Please help me where i am going wrong
//global indexpath to remember which cell tapped
NSIndexPath *globalPath;
#interface SearchViewController ()
#end
#implementation SearchViewController
//Load implementation once per launch
- (void)viewDidLoad
{
[super viewDidLoad];
[self linkInputTableToDelegate];
_temporaryResultsArray =[[NSMutableArray alloc]init];
_flurryArray=[[NSMutableArray alloc]init];
_numberOfSections=6;
}
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:NO];
[InputTable reloadData];
textFromUserDefaults=[[[HelperMethods alloc]init]getObjectUserDefault:#"textFiltered"];
[self addTextToFlurryArrayForFlurryAndSavedLists:_textFromUserDefaults];
}
-(void)viewDidDisappear:(BOOL)animated{
}
- (IBAction)searchButtonPressed:(UIButton *)sender {
self.tabBarController.selectedIndex = 1;
}
//Makes the input table respond to delegate table view methods
-(void)linkInputTableToDelegate{
_inputTable.dataSource=self;
_inputTable.delegate=self;
}
-(void)performSearch:(NSString*)text{
//do search
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
int numberOfRows=_numberOfSections;
//Rows for iPhone 4
if ([[UIScreen mainScreen]bounds].size.height==480) {
numberOfRows=numberOfRows;
//Rows for iPhone 5
}else if ([[UIScreen mainScreen]bounds].size.height==568){
numberOfRows=numberOfRows+1;
}
return numberOfRows;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
//In reality groups are created with 1 row inside, this is to allow spacing between the rows
return 1;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *kCellID = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellID];
if (!cell) {
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCellID];
}
//Is the cell the same as the one clicked when going to ingredient filter
BOOL cellIndexPathSameAsSelected=[self isCellIndexSameAsPreviousClicked:indexPath];
cell.textLabel.textColor=[UIColor blackColor];
if (cellIndexPathSameAsSelected && _textFromUserDefaults!=nil) {
if (![cell.textLabel.text isEqualToString:_textFromUserDefaults]) {
cell.textLabel.text=_textFromUserDefaults;
[self performTextSearch:_textFromUserDefaults];
}
}
return cell;
}
//Compares the previous clicked cell with the cell now selected
-(BOOL)isCellIndexSameAsPreviousClicked: (NSIndexPath*)cellPath{
if (cellPath.row == globalPath.row && globalPath.section==cellPath.section) {
return YES;
}
else{
return NO;
}
}
- (void)updateTableViewWithExtraRow :(NSIndexPath*)rowSelected{
NSLog(#"number of sections =%i",_numberOfSections);
if (rowSelected.section == _numberOfSections) {
_numberOfSections ++;
}
}
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *cellText = [tableView cellForRowAtIndexPath:indexPath].textLabel.text;
[[[HelperMethods alloc]init]saveObjectToUserDefaults:cellText :#"textFiltered"];
globalPath = indexPath;
[self updateTableViewWithExtraRow:indexPath];
}
-(void)addTextToFlurryArrayForFlurryAndSavedLists:(NSString*)text{
if ([_flurryArray count]==0 &&[text length]>0) {
[_flurryArray addObject:text];
}
for (int i=0;i<[_flurryArray count];i++) {
NSString *textInArray=[_flurryArray objectAtIndex:i];
if (![textInArray isEqualToString:text]) {
[_flurryArray addObject:text];
}
}
NSLog(#"Total number of saved items = %i",[_flurryArray count]);
}
// Dispose of any resources that can be recreated.
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
I have a couple of reactions looking at the code:
A couple of observations about the proper use of the UITableViewDataSource methods, specifically numberOfRowsInSection, numberOfSectionsInTableView, and cellForRowAtIndexPath:
These really should be driven by some model data structure (e.g. a NSMutableArray) and nothing else;
These methods should be stateless. They should not relying on the value of some NSString instance variable, like _textFromUserDefaults) but rather always look up the value in the NSMutableArray model structure on the basis of the value of the indexPath parameter. You simply cannot make any assumptions about when cellForRowAtIndexPath will be called. This may well account for your duplicate values.
None of these should be doing anything besides responding to the UITableView inquiry. For example, your cellForRowAtIndexPath is invoking performTextSearch. It really shouldn't do anything except return the cell.
Your cellForRowAtIndexPath currently has conditional logic and only updates the cell if certain conditions holds. Because cells are reused, you really want to make sure that you initialize the cells regardless. You can't be assured that the cell is blank when you get it, nor that the previous contents are the previous values for that indexPath. Because cells are reused, it could be for an entirely different row. This could also account for your duplicative entries.
Regarding the interaction of the master view controller and the details view controller, there are more elegant ways than passing data back and forth via NSUserDefaults. For example when you initiate the details view controller, you could just pass it the information it needs. And when it's done, it should call a method in the master view controller to update the data in the master view. To do that, the master view controller should conform to some protocol of your own creation. If you see the example I shared via chat, you can see what that might look like. Anyway, by having some delegate method in the master view controller that the detail view controller calls when it's done, that eliminates the rather fragile technique of using viewDidAppear to control the updating of the master table view.
You might want to contemplate employing "edit" (which allows you to delete, possibly also edit a particular row) and "add" buttons like the standard "master-detail" template that Xcode provides. There are a number of standard conventions here that might be better than having an array of blank cells that you can then tap on. Clearly, your user experience is entirely up to you, but you can always contemplate whether there are existing, familiar conventions that you might employ.
Rob's feedback is good. In broader terms, you can't rely on the cells in a UITableView to hold onto their data. For efficiency, it will be creating, using, and destroying cells at will, and using cellForRowAtIndexPath to figure out what they should look like. Instead of testing what's in a cell, you need to have your own set of data which describe the value of each cell, and just set the value based on the indexPath. I'd recommend storing all your cell information in an NSMutableArray which contains NSStrings or something more complicated if necessary. It will be easy to set default values when you add cells to the array. Then cellForRowAtIndexPath can just access the array rather than attempting its own logic based on current cells.

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