TableView Controller using JSON NSURL - objective-c

Question

Good afternoon,
I'm trying to use a TableView Controller to display X number of items from my MySQL database but I'm a little bit lost at the moment.
I have another project where I can show the data using JSON output data, but I don't know how to add that code to my project in order to show the data from my database. That's the code I used:
#implementation HomeModel
- (void)downloadItems
{
// Download the json file
NSURL *jsonFileUrl = [NSURL URLWithString:#"http://website.com/service.php"];
// Create the request
NSURLRequest *urlRequest = [[NSURLRequest alloc] initWithURL:jsonFileUrl];
// Create the NSURLConnection
[NSURLConnection connectionWithRequest:urlRequest delegate:self];
}
#pragma mark NSURLConnectionDataProtocol Methods
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
// Initialize the data object
_downloadedData = [[NSMutableData alloc] init];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
// Append the newly downloaded data
[_downloadedData appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
// Create an array to store the locations
NSMutableArray *_locations = [[NSMutableArray alloc] init];
// Parse the JSON that came in
NSError *error;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData:_downloadedData options:NSJSONReadingAllowFragments error:&error];
// Loop through Json objects, create question objects and add them to our questions array
for (int i = 0; i < jsonArray.count; i++)
{
NSDictionary *jsonElement = jsonArray[i];
// Create a new location object and set its props to JsonElement properties
Location *newLocation = [[Location alloc] init];
newLocation.name = jsonElement[#"user"];
newLocation.address = jsonElement[#"imagen"];
newLocation.latitude = jsonElement[#"date"];
// Add this question to the locations array
[_locations addObject:newLocation];
}
// Ready to notify delegate that data is ready and pass back items
if (self.delegate)
{
[self.delegate itemsDownloaded:_locations];
}
}
#end
Currently that's my code:
TableViewController.m
#import "CarTableViewController.h"
#import "CarTableViewCell.h"
#import "CarTableViewController.h"
#import "CarDetailViewController.h"
#implementation CarTableViewController
#synthesize carMakes = _carMakes;
#synthesize carModels = _carModels;
#synthesize carImages = _carImages;
- (void)viewDidLoad
{
[super viewDidLoad];
self.carMakes = [[NSArray alloc]
initWithObjects:#"Chevy",
#"BMW",
#"Toyota",
#"Volvo",
#"Smart", nil];
self.carModels = [[NSArray alloc]
initWithObjects:#"Volt",
#"Mini",
#"Venza",
#"S60",
#"Fortwo", nil];
self.carImages = [[NSArray alloc]
initWithObjects:#"chevy_volt.jpg",
#"mini_clubman.jpg",
#"toyota_venza.jpg",
#"volvo_s60.jpg",
#"smart_fortwo.jpg", nil];
}
- (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 [self.carModels count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"carTableCell";
CarTableViewCell *cell = [tableView
dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[CarTableViewCell alloc]
initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier];
}
// Configure the cell...
cell.makeLabel.text = [self.carMakes
objectAtIndex: [indexPath row]];
cell.modelLabel.text = [self.carModels
objectAtIndex:[indexPath row]];
UIImage *carPhoto = [UIImage imageNamed:
[self.carImages objectAtIndex: [indexPath row]]];
cell.carImage.image = carPhoto;
return cell;
}
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"ShowCarDetails"])
{
CarDetailViewController *detailViewController =
[segue destinationViewController];
NSIndexPath *myIndexPath = [self.tableView
indexPathForSelectedRow];
detailViewController.carDetailModel = [[NSArray alloc]
initWithObjects: [self.carMakes
objectAtIndex:[myIndexPath row]],
[self.carModels objectAtIndex:[myIndexPath row]],
[self.carImages objectAtIndex:[myIndexPath row]],
nil];
}
}
#end
TableViewController.h
#import <UIKit/UIKit.h>
#interface CarTableViewController : UITableViewController
#property (nonatomic, strong) NSArray *carImages;
#property (nonatomic, strong) NSArray *carMakes;
#property (nonatomic, strong) NSArray *carModels;
#end
How can I add the first code (results from my database) to the other project? I'm lost at the moment and I will appreciate a lot if you can give me some light on this problem, because I want to edit the info from the storyboard as I have in the second project.
Thanks in advance.
Regards.
Thanks in advance.

Answer 1

It's because you don't connect to your database directly from your iphone. In general ou have a web service (also call API) for expose your data (in JSON format for example). So you have to build an API, in PHP, Ruby or Node, for expose the data of your database and access it.
EDIT:
What i see is in your HomeModel, you can set a delegate, this delegate have a function itemsDownloaded where you pass the data get from your API.
So you want your CarTableViewController to be that delegate for receive those data.
First you have to have an object HomeModel, in your TableViewController.h add:
#property (strong, nonatomic) HomeModel *homeModel;
Now you have to call the code that get the data from your server. Something like
- (void)viewDidLoad
{
[super viewDidLoad];
homeModel = [HomeModel new];
homeModel.delegate = self;
[homeModel downloadItems];
}
And finally you have to implement itemsDownloaded in your CarTableViewController. Do something like this:
- (void)itemsDownloaded:(NSArray *)items
{
self.carMakes = items; // Problem here
[self.tableView reloadData];
}
But the problem is HomeModel parse something different from what you have in carMakes, you have to adapt the Loop through Json objects in HomeModel.
You may wanna try AFNetworking which is a library easier to use than NSURLConnection.