ios - struggling to populate a UITableView from an NSArray - ios

Question

I have this code:
#interface MyBusinessesController : UIViewController
{
NSDictionary *businesses;
NSArray *items_array;
}
#property (weak, nonatomic) IBOutlet UILabel *messageLabel;
- (IBAction)plan:(id)sender;
#property (weak, nonatomic) IBOutlet UITableView *itemList;
#end
and I set the UITableView and the NSArray in the header area of the .m file. Then I have a remote server call and get back JSON. I get the JSON data into an array like this:
items_array = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
Then I loop through the items like this:
for (int i = 0; i<= items_array.count - 1; i++)
{
NSDictionary *dict = [items_array objectAtIndex:i];
NSString *item_title = [dict objectForKey:#"item_title"];
NSString *item_id = [dict objectForKey:#"item_id"];
...
and then I would like to add it as a row in my UITableView, but I am struggling with how to do it now.
What I would want is to display the item_title to the user, and when the user presses the title that I would be able to know how to get the item_id of that item_title.
Thank you!

Answer 1

You need to implement the required methods in the UITableViewDataSource protocol, and set the dataSource property of the tableView to self.
Accordingly, implement the appropriate UITableViewDelegate methods, and set the delegate property of your tableView to self.
See the documentation for details on which methods are required, and which optional methods you might want to implement.
Don't forget to advertise in your .h file that your Class conforms to both protocols:
#interface MyBusinessesController : UIViewController <UITableViewDataSource, UITableViewDelegate>
You can make the tableView refresh its content by calling [itemList reloadData].

Answer 2

Table views work differently to what you appear to be used. You don't loop over your data and fill the table. Instead, you set yourself as table's delegate and then the table will ask you:"How much data do you have, what data do you want at row 5" and so on.
I'd really suggest you go over this great tutorial here:
http://kurrytran.blogspot.com/2011/10/ios-5-storyboard-uitableview-tutorial.html

Answer 3

Instead of looping through the array and pulling out the string values you can let the data source methods for UITableView handle this. So in cellForRowAtIndexPath method you would index your items_array with the index path as such:
NSDictionary *dict = [items_array objectAtIndex:[indexPath row]];
Then you would pull the strings out of the dictionary like you did in the loop and set the title for the cell to the string. For selecting the cell, you can write your code in the didSelectRowAtIndexPath method.
Here is an example from a project I was working on:
#pragma mark - Table view data source
- (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 [items_array count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:(UITableViewCellStyleDefault)
reuseIdentifier:#"cell"];
NSDictionary *dict = [items_array objectAtIndex:[indexPath row]];
cell.textLabel.text = [dict objectForKey:#"item_name"];
return cell;
}
The first method specifies the number of sections you want in your table. If you want a very simple table this will be 1. The second method is the number of rows. This will be the number of items in your items_array so: [items_array count]. The third method creates a cell based on the index. It will go from section 0 to the number of sections you specify and from row 0 to number of rows per section you specify. So now instead of looping you can just index out your array. [indexPath section] gives the section number and [indexPath row] gives the row number.
*I know I should probably dequeue cells before making new ones but my array is very small.