Populating Custom TableViewCell from Twitter using JSON Serialization - objective-c

I am new to Objective-C. I spent countless hours being stuck on getting a blank tableview, I am desperate at this point.
I am loading twitter data through a JSON call, using their API. I store everything in a NSDictionary, run a for loop to select only "text" values. I store the filtered dictionary in an object which I later use in the TableView initialization.
I created a subclass of UItableViewCell for my custom cell.
My dataSources and delegates seem to be well connected as well (that is what I think at least)
I am having a hard time finding my problem. If someone could help me out please.
#import "ViewController.h"
#import "myCell.h"
#import <TwitterKit/TwitterKit.h>
#interface ViewController ()
#end
#implementation ViewController
#synthesize myTableView;
NSMutableArray *tweetObject;
NSDictionary *dictionary;
NSString *name;
NSString *text;
- (void)viewDidLoad {
tweetObject = [[NSMutableArray alloc] init];
[super viewDidLoad];
self.myTableView.dataSource = self;
self.myTableView.delegate = self;
text = #"text";
[[Twitter sharedInstance] logInGuestWithCompletion:^(TWTRGuestSession *guestSession, NSError *error) {
if (guestSession) {
// make API calls that do not require user auth
NSString *statusesShowEndpoint = #"https://api.twitter.com/1.1/statuses/user_timeline.json?screen_name=goofernator";
NSError *clientError;
NSURLRequest *request = [[[Twitter sharedInstance] APIClient]
URLRequestWithMethod:#"GET"
URL:statusesShowEndpoint
parameters:0
error:&clientError];
if (request) {
[[[Twitter sharedInstance] APIClient]
sendTwitterRequest:request
completion:^(NSURLResponse *response,
NSData *data,
NSError *connectionError) {
if (data) {
// handle the response data e.g.
NSError *jsonError;
NSDictionary *json = [NSJSONSerialization
JSONObjectWithData:data
options:0
error:&jsonError];
for (NSDictionary *dataDict in json) {
NSString *text = [dataDict valueForKeyPath: #"text"];
dictionary = [NSDictionary dictionaryWithObjectsAndKeys:text,#"bodytext",nil];
[tweetObject addObject:dictionary];
}
}
else {
NSLog(#"Error: %#", connectionError);
}
}];
}
else {
NSLog(#"Error: %#", clientError);
}
} else {
NSLog(#"error: %#", [error localizedDescription]);
}
}];
}
- (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 tweetObject.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
myCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell=[[myCell alloc]initWithStyle:
UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
}
NSDictionary *tmpDict = [self.tweetObject objectAtIndex:indexPath.row];
cell.txtLblOutput.text = [tmpDict objectForKey:text];
[tableView reloadData];
return cell;
}
#end
Here you can see the way my storyboard is put together and the references I am using
http://postimg.org/image/79w7pqmu3/
http://postimg.org/image/ixq9kabyz/

You should call [tableView reloadData]; in your request completion handler, after you've filled your array. Check if you receive any data. Does the array get filled with dictionary objects?
But mate, seriously, you need to read some good books about coding, your code really lacks understanding of what you're doing. Please, remove [tableView reloadData]; from the - ...cellForRowAtIndexPath:... method.

Related

Predefine a specific twitter feed to display

In the code below, a tableview displays the twitter feed of the user of the phone. All I want to do is display the feed of a user that I predefine in the code. I looked online but can't find any tutorials on this. I would like to edit this code instead of restarting with a third party API.
ViewController.m
#import "TwitterViewController.h"
#import <Accounts/Accounts.h>
#import <Social/Social.h>
#interface TwitterViewController ()
#property (strong, nonatomic) NSArray *twitterArray;
#end
#implementation TwitterViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
[self twitterTimeline];
// Do any additional setup after loading the view from its nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)twitterTimeline {
ACAccountStore *account = [[ACAccountStore alloc] init]; // Creates AccountStore object.
// Asks for the Twitter accounts configured on the device.
ACAccountType *accountType = [account accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
[account requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error)
{
// If we have access to the Twitter accounts configured on the device we will contact the Twitter API.
if (granted == YES){
NSArray *arrayOfAccounts = [account accountsWithAccountType:accountType]; // Retrieves an array of Twitter accounts configured on the device.
// If there is a leat one account we will contact the Twitter API.
if ([arrayOfAccounts count] > 0) {
ACAccount *twitterAccount = [arrayOfAccounts lastObject]; // Sets the last account on the device to the twitterAccount variable.
NSURL *requestAPI = [NSURL URLWithString:#"http://api.twitter.com/1.1/statuses/user_timeline.json"]; // API call that returns entires in a user's timeline.
// The requestAPI requires us to tell it how much data to return so we use a NSDictionary to set the 'count'.
NSMutableDictionary *parameters = [[NSMutableDictionary alloc] init];
[parameters setObject:#"100" forKey:#"count"];
[parameters setObject:#"1" forKey:#"include_entities"];
// This is where we are getting the data using SLRequest.
SLRequest *posts = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodGET URL:requestAPI parameters:parameters];
posts.account = twitterAccount;
// The postRequest: method call now accesses the NSData object returned.
[posts performRequestWithHandler:
^(NSData *response, NSHTTPURLResponse
*urlResponse, NSError *error)
{
// The NSJSONSerialization class is then used to parse the data returned and assign it to our array.
self.twitterArray = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableLeaves error:&error];
if (self.twitterArray.count != 0) {
dispatch_async(dispatch_get_main_queue(), ^{
[self.twitterFeedTable reloadData]; // Here we tell the table view to reload the data it just recieved.
});
}
}];
}
} else {
// Handle failure to get account access
NSLog(#"%#", [error localizedDescription]);
}
}];
}
#pragma mark Table View Data Source Mehtods
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
// Returns the number of rows for the table view using the array instance variable.
return [_twitterArray count];
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
// Creates each cell for the table view.
static NSString *cellID = #"CELLID" ;
UITableViewCell *cell = [self.twitterFeedTable dequeueReusableCellWithIdentifier:cellID];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellID];
}
// Creates an NSDictionary that holds the user's posts and then loads the data into each cell of the table view.
NSDictionary *tweet = _twitterArray[indexPath.row];
cell.textLabel.text = tweet[#"text"];
return cell;
}
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// When a user selects a row this will deselect the row.
[self.twitterFeedTable deselectRowAtIndexPath:indexPath animated:YES];
}
#end
The information is here in the docs.
You need to add either a user_id parameter or a screen_name parameter to your http://api.twitter.com/1.1/statuses/user_timeline.json request, and that's all.
Example as provided in the documentation:
https://api.twitter.com/1.1/statuses/user_timeline.json?screen_name=twitterapi

Hiding an autocomplete UITableView that was created programmatically

I'm building an application with an autocomplete UITableView from this tutorial. I have the autocomplete functionality working properly, but I would like the UITableView-autocomplete drop down to disappear when the word is clicked on or when it is touched up outside. I'm not sure how to set up a delegate when the object is set up programmatically. I've only done this using the interface builder.
.h
#interface slrpViewController : UIViewController<UITextFieldDelegate, UIPickerViewDelegate, UIPickerViewDataSource>
{
NSMutableArray *dataArray;
NSMutableData *receivedData;
NSMutableArray *pastUrls;
NSMutableArray *autocompleteUrls;
UITableView *autocompleteTableView;
}
#property(nonatomic, retain) IBOutlet UITextField *eWordEntered;
#property (nonatomic, retain) NSMutableArray *pastUrls;
#property (nonatomic, retain) NSMutableArray *autocompleteUrls;
#property (retain, nonatomic) NSMutableData *responseData;
#property (nonatomic, retain) UITableView *autocompleteTableView;
-(void)setReceivedData:(NSMutableData*)pReceivedData;
-(NSMutableData *) getReceivedData;
-(void) getAutoCompleteArray;
-(void)searchAutocompleteEntriesWithSubstring:(NSString *)substring;
.m
- (void)viewDidLoad
{
[super viewDidLoad];
[self getAutoCompleteArray];
pastUrls = [[NSMutableArray alloc] init];
NSLog(#"In the viewDidLoad and pasturl is: %#", self.pastUrls);
self.autocompleteUrls = [[NSMutableArray alloc] init];
autocompleteTableView = [[UITableView alloc] initWithFrame:CGRectMake(210, 225, 310, 120) style:UITableViewStylePlain];
self.autocompleteTableView.delegate = self;
self.autocompleteTableView.dataSource = self;
autocompleteTableView.scrollEnabled = YES;
autocompleteTableView.hidden = YES;
[self.view addSubview:autocompleteTableView];
-(void)setReceivedData:(NSMutableData*)pReceivedData
{
receivedData = pReceivedData;
}
-(NSMutableData *) getReceivedData{
return receivedData;
}
-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[receivedData setLength:0];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{[receivedData appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSError *e = nil;
NSError *error = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: receivedData options: NSJSONReadingMutableContainers error: &e];
NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:receivedData
options:kNilOptions
error:&error];
seneca_word.ids = [jsonDict objectForKey:#"ids"];
NSArray *array_ids = [jsonDict objectForKey:#"ids"];
NSString *ids = array_ids[0];
seneca_word.ids = ids;
for (id key in jsonDict)
{
NSLog(#"key: %#, value: %#", key, [jsonDict objectForKey:key]);
NSLog(#"The value of bases by itself is: %#", [jsonDict objectForKey:#"bases"]);
}
if (!jsonArray)
{
NSLog(#"Error parsing JSON: %#", e);
}
else
{
if([jsonDict objectForKey:#"english"] != nil){
pastUrls = [jsonDict objectForKey:#"bases"];
}
else{
//Some of JSON object that I don't want to use here
}//else
}//(void)connectionDidFinishLoading
- (void)searchAutocompleteEntriesWithSubstring:(NSString *)substring {
[autocompleteUrls removeAllObjects];
for(NSString *curString in pastUrls) {
NSRange substringRange = [curString rangeOfString:substring];
if (substringRange.location == 0) {
[autocompleteUrls addObject:curString];
}
}
[autocompleteTableView reloadData];
}
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
autocompleteTableView.hidden = NO;
NSString *substring = [NSString stringWithString:textField.text];
substring = [substring stringByReplacingCharactersInRange:range withString:string];
[self searchAutocompleteEntriesWithSubstring:substring];
return YES;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger) section {
return autocompleteUrls.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = nil;
static NSString *AutoCompleteRowIdentifier = #"AutoCompleteRowIdentifier";
cell = [tableView dequeueReusableCellWithIdentifier:AutoCompleteRowIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:AutoCompleteRowIdentifier];
}
cell.textLabel.text = [autocompleteUrls objectAtIndex:indexPath.row];
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *selectedCell = [tableView cellForRowAtIndexPath:indexPath];
self.eWordEntered.text = selectedCell.textLabel.text;
if(tableView == autocompleteTableView){
//The autocomplete table view is the one that fired the didSelect delegate method
//So hide the autocomplete table.
//do whatever else you need to do to empty the autocompleteTableView's data source
//or/and simply hide the table after that
[autocompleteTableView setHidden:YES];
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
//When the user clicks outside of the uitableview it will disappear
[autocompleteTableView setHidden:YES];
}
As you can see I populate the autocomplete UITableView with JSON data that I'm getting from a RESTful API.
I'm getting the warning, Assigning to 'id<UITableViewDelegate>' from incompatible type 'ViewController *const __strong' for the lines:
self.autocompleteTableView.delegate = self;
self.autocompleteTableView.dataSource = self;
I imagine once I get the delegate stuff sorted out I'll be able to do what I want. I did some research and tried to create a delegate class but wasn't able to get that solution working. I'm not even sure if that's the right way to go about this as I usually do this stuff by interface builder and not programmatically. Any direction or help is greatly appreciated. Thanks!
You should be using the tableView's didSelectCellAtIndexPathRow delegate method to identify user taps on a cell from a tableView. It's ok if you created your tableView progammatically.
Simply make sure the UIViewController conforms to the UITableViewDelegate and UITableViewDataSource` protocols.
make sure you set the tableView's delegate and dataSource property to self.
Implement the didSelectCellAtIndexPathRow delegate method in your viewController's .m file like so:
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
}
Then inside that delegate method you need to help detect from which tableView your didSelect method got fired from as you only want to hide the autocomplete table when the user selects a cell from that table. So you do a simple tableView check like so:
if(tableView == autocompleteTableView){
//The autocomplete table view is the one that fired the didSelect delegate method
//So hide the autocomplete table.
//do whatever else you need to do to empty the autocompleteTableView's data source
//or/and simply hide the table after that
[autocompleteTableView setHidden:YES];
}
You probably also want to make sure that you set the autocompleteTableView hidden property to NO when the user types in something in the textfield so that the auto complete can show appear again.
And thats all buddy.
try setting self.autocompleteTableView.hidden = YES;

Dispatch Queue and global NSMutableDictionary - Objective C

I'm trying to use a global NSMutableDictionary from a dispatch queue. However, the items keep coming back NULL.
What I'm trying to do is access an external json file with a dispatch_queue, then populate a UITableView with this info.
Here's what I have
vc.h:
#interface viewcontroller {
NSMutableDictionary *jsonArray;
}
vc.m:
#define kBgQueue dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0) //1
#define jsonTest [NSURL URLWithString:#"http://www.sometest.com/test.php"]
-(void)viewDidLoad {
dispatch_async(kBgQueue, ^{
NSData* data = [NSData dataWithContentsOfURL:
jsonTest];
[self performSelectorOnMainThread:#selector(fetchedData:)
withObject:data waitUntilDone:YES];
// if I run the log here, I can access jsonArry and the log prints correctly
NSLog(#"City: %#", [jsonArray objectForKey:#"city"];
});
}
-(NSMutableDictionary *)fetchedData:(NSData *)responseData {
NSError *error;
jsonArray = [NSJSONSerialization JSONObjectWithData:responseData options:kNilOptions error:&error];
return jsonArray;
}
/********************* Table formatting area **********************/
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (tableView == self.ipTable) {
if ([ipArray count] == 0){
return 1;
} else { // meta table
return [ipArray count];
}
} else { // IP Meta Data
return [jsonArray count];
}
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
if (tableView == self.myTable) {
NSString *CellIdentifier = NULL;
if ([ipArray count] == 0) {
CellIdentifier = #"No Cells";
} else {
CellIdentifier = #"IP Cell";
}
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
if ([ipArray count] == 0)
{
[cell.textLabel setText:NSLocalizedString(#"None Found", nil)];
return cell;
} else {
IPAddr *theip = [ipArray objectAtIndex: [indexPath row]];
NSString *theipname = [theip ipName];
if ([theipname isEqualToString:#""]) {
[cell.textLabel setText: [theip ipNum]];
[cell.detailTextLabel setText:NSLocalizedString(#"noName", nil)];
} else {
[cell.textLabel setText: [theip ipName]];
[cell.detailTextLabel setText: [theip ipNum]];
}
return cell;
}
} else { // meta table
static NSString *CellIdentifier = #"metaCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// jsonArray content would go here to fill the cells.
/******************** something here to fill the cells using jsonArray ********************/
return cell;
}
} // END UITAbleViewCell
If I access the jsonArray inside the queue, it returns fine and prints the log for the city.
However, if I try to use it outside the queue, it returns NULL.
I'm trying to figure out what is happening, any ideas?
I need to use jsonArray in different methods in the same view, so I need it to be global.
I am fairly sure that the problem is that the data source methods (numberOfRowsInSection,
cellForRowAtIndexPath) are called before the background thread has finished and
filled the jsonArray. Therefore you have to reload the table view when the background
thread has finished:
- (void)viewDidLoad
{
[super viewDidLoad];
dispatch_async(kBgQueue, ^{
NSData *data = [NSData dataWithContentsOfURL:jsonTest];
NSError *error;
NSArray *tmpArray = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&error];
dispatch_sync(dispatch_get_main_queue(), ^{
// Assign new data to data source and reload the table view:
jsonArray = tmpArray;
[self.metaTableView reloadData];
});
});
}
So the table view would be empty initially, and reloaded later when the data has
arrived.
Try to call the other method(which is using your jsonarray) through nsnotification...I am not sure there might some other ideas/ways of doing this.But i am presenting what i have in my mind.
Put this code inside your fetchedData method,
NSNotificationCenter *nc = [NSNotificationCenter defaultCenter];
[nc addObserver:self selector:#selector(someMethod:) name:#"JSonDownloaded" object: jsonArray];
[[NSNotificationCenter defaultCenter] postNotificationName:#"JSonDownloaded" object: jsonArray];
-(void)someMethod:(NSNotification *)nspk
{
NSLog(#"%#",nspk.object);
//Only after this you can able to access the jsonArray.
}
Don't forget to unregister the observer.
jsonArray is just an instance variable, but not a property. Thus, assigning an object to it does not retain it, and the object may be released as soon as the program returns to the run loop.
I suggest replacing the iVar by #property (strong) NSMutableDictionary *jsonArray; and #synthesize jsonArray;, and assigning the object to it by self.jsonArray = ...
EDIT (see comment of Martin R below):
Thus, if you are not using ARC, assigning an object to it does not retain it, and the object may be released as soon as the program returns to the run loop.
In this case, I suggest replacing the iVar by #property (retain) NSMutableDictionary *jsonArray; and #synthesize jsonArray;, and assigning the object to it by self.jsonArray = ...

Error when swipe to delete a table cell

I'm trying to delete a row when user swipes. I got this error driving me crazy. I've spent last three hours trying to figure out why. But, I have got no clue so far.
Here is my code to accomplish that.
in .h
#import <UIKit/UIKit.h>
#import "CustomCell.h"
#interface FollowersTableViewController : UITableViewController
#property (nonatomic,strong)NSMutableArray *arrayWithUser ;
#end
and in .m i have this code .
#import "FollowersTableViewController.h"
#implementation FollowersTableViewController
#synthesize arrayWithUser ;
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
-(void)viewDidLoad
{
[super viewDidLoad];
NSDictionary *dicUrlList= [NSDictionary dictionaryWithContentsOfFile:[[NSBundle mainBundle] pathForResource:#"Urls" ofType:#"plist"]];
NSString *baseURl = [dicUrlList objectForKey:#"urlWithUser"];
baseURl = [baseURl stringByAppendingFormat:#"getfollowers"];
NSURL *urlToGetFollowers = [NSURL URLWithString:baseURl];
NSURLRequest *request = [NSURLRequest requestWithURL:urlToGetFollowers];
NSError *error = nil ;
NSURLResponse *response = nil ;
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
arrayWithUser = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
}
- (void)viewDidUnload
{
[super viewDidUnload];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [arrayWithUser count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *MyIdentifier = #"Cell";
CustomCell *customCell = (CustomCell *)[tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if (customCell == nil)
{
customCell = [[CustomCell alloc] initWithFrame:CGRectMake(0, 0, 320, 50)] ;
}
NSDictionary *dicWithUser = [arrayWithUser objectAtIndex:indexPath.row];
NSString *photoUrl = [dicWithUser objectForKey:#"profilePhotoUrl"];
if(![photoUrl isEqualToString:#""])
[customCell.thumbnail setImageWithURL:[dicWithUser objectForKey:#"profilePhotoUrl"] placeholderImage:[UIImage imageNamed:#"placeholder.png"] ];
else
{
[customCell.thumbnail setImage:[UIImage imageNamed:#"placeholder.png"]];
}
customCell.titleLabel.text = [dicWithUser objectForKey:#"username"];
UIButton *buttonFollow = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[buttonFollow setTitle:#"Follow" forState:UIControlStateNormal];
CGRect frame = buttonFollow.frame ;
frame = CGRectMake(200, 10, 60, 30);
buttonFollow.frame = frame ;
buttonFollow.tag = indexPath.row ;
[buttonFollow addTarget:self action:#selector(followButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
customCell.accessoryView = buttonFollow ;
return customCell;
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return 60 ;
}
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the specified item to be editable.
return YES;
}
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete) {
// Delete the row from the data source
[arrayWithUser removeObjectAtIndex:indexPath.row];
}
}
So far,I'm able to see delete button, but when i pressed it gives me this error
[__NSCFArray removeObjectAtIndex:]: mutating method sent to immutable object.
Since I've already used NSMutableArray, I've no idea, why I'm getting this error?
I've already try to clean project. It didn't make any difference.
Your Json call returning an NSArray. You can go to create a mutableCopy - so you're will be able to use the "removeAtIndex.." method.
NSArray *rData = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
arrayWithUser = [rData mutableCopy];
The assignment to arrayWithUser from the JSON call is returning an NSArray not an NSMutableArray in viewDidLoad. Fix that.
Actually, your array(arrayWithUser) is strongly pointing to the array return by the JSONObjectWithData, as you don't have the ownership of the returned array, you can't remove its object.
You better do one thing ,take ownership of that array.
arrayWithUser = [[NSMutableArray alloc]arrayByAddingObjectsFromArray:[NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil]];
Just replace below line
arrayWithUser = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
with
arrayWithUser = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
From Apple's documentation:
NSJSONReadingMutableContainers: Specifies that arrays and dictionaries are created as mutable objects.
NSJSONReadingMutableLeaves: Specifies that leaf strings in the JSON object graph are created as instances of NSMutableString.
You used in viwDidLoad
arrayWithUser = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
Lets try like this
NSMutableArray *userMutarr = [NSMutableArray alloc]initWithCapacity:3];
self.arrayWithUser = userMutarr;
[userMutarr release];
Then
self.arrayWithUser = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];

iOS 5 JSON to tableView error

I was trying to parse a JSON string from USGS. However I get error "-[__NSCFDictionary objectAtIndex:]: unrecognized selector sent to instance 0x68a34c0" Basically, I would like to parse the USGS JSON into the tableview. Can anyone help? Here are my codes.
ViewController.h
#interface EarthquakeViewController : UITableViewController
{
NSArray *json;
NSDictionary *earthquakeReport;
}
ViewController.m
- (void)viewDidLoad
{
//content = [NSMutableArray arrayWithObjects:#"one", #"two", nil];
[super viewDidLoad];
[self fetchReports];
}
- (void)fetchReports
{
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
NSData* data = [NSData dataWithContentsOfURL:
[NSURL URLWithString: #"http://earthquake.usgs.gov/earthquakes/feed/geojson/all/hour"]];
NSError* error;
json = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];
NSLog(#"%#", json);
dispatch_async(dispatch_get_main_queue(), ^{
[self.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 json.count;
}
- (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];
}
earthquakeReport = [json objectAtIndex:indexPath.row];
NSString *country = [[[earthquakeReport objectForKey:#"features"] objectForKey:#"properties"] objectForKey:#"place"];
NSString *mag = [[[earthquakeReport objectForKey:#"features"] objectForKey:#"properties"] objectForKey:#"mag"];
cell.textLabel.text = country;
cell.detailTextLabel.text = mag;
return cell;
}
The error is showing at the line earthquakeReport = [json objectAtIndex:indexPath.row];
If you look at your JSON data in a web browser (http://earthquake.usgs.gov/earthquakes/feed/geojson/all/hour) you should notice that the array you are trying to access is not at the root level. The root level is a dictionary, and the array you're looking for is in the "features" key.
To access it properly, first change your json ivar declaration into an NSDictionary:
NSDictionary *json;
Then, in your tableView:cellForRowAtIndexPath: method, access the report thusly:
earthquakeReport = [[json objectForKey:#"features"] objectAtIndex:indexPath.row];