如何将NSDictionary数据放入UITableView

Question

I have 2 NSArrays that I'm trying to link together in an NSDictionary so that each providerName has a providerId associated with it.

I expected the two arrays to be associated with each other using self.providersDict = [NSDictionary dictionaryWithObjects:providerName forKeys:providerId]; and then the providerName to be displayed as the table cell title and the id as the table cell subtitle.

At the moment I can't get the data displayed on the UITable or even log out the dictionary using:

   for (id key in self.providersDict) {
    NSLog(@"key: %@, value: %@", key, [self.providersDict objectForKey:key]);
}

declared in the .h:

NSArray *providerName;
NSArray *providerId;

@property (nonatomic, strong) NSDictionary *providersDict;

and in the viewDidLoad:

    providerName = [NSArray arrayWithObjects:@"provider1", @"provider2", @"provider3", nil];
    providerId = [NSArray arrayWithObjects:@"1", @"2", @"3", nil];

    self.providersDict = [NSDictionary dictionaryWithObjects:providerName
                                                           forKeys:providerId];

the UITable methods:

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [[self.providersDict allKeys] count];
}


-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{



 static NSString *unifiedID = @"aCellID";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:unifiedID];
    if (!cell) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:unifiedID];

}

for (id key in self.providersDict) {
    NSLog(@"key: %@, value: %@", key, [self.providersDict objectForKey:key]);
}

NSString *providerNameString = [self.providersDict objectForKey:@"provider"];
NSString *providerIdString = [self.providersDict objectForKey:@"object"];
cell.textLabel.text  = providerNameString;
cell.detailTextLabel.text  = providerIdString;


return cell;

}

thanks for the help.

Answer 1

NSString *providerNameString = [self.providersDict objectForKey:@"provider"];
NSString *providerIdString = [self.providersDict objectForKey:@"object"];

You have initialized self.providersDict with keys 1, 2, 3. So you should Try to fetch providerNameString using those keys and not @"provider" same for providerIdString .

Try

NSString *key = [self.providersDict allKeys][indexPath.row];

NSString *providerNameString = self.providersDict[key];
NSString *providerIdString = key;
cell.textLabel.text  = providerNameString;
cell.detailTextLabel.text  = providerIdString;

And don't forget to call [tableView reloadData]; once your self.providersDict is initialized.

As for a suggestion why dont you create a Model Class for Provider with id, name and other information. You can add each provider in an array and would make your life a lot easier.

Answer 2

For your purpose , you don't need any NSDictionary , simply use two NSArrays to populate the data in UITableView

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{
    static NSString *unifiedID = @"aCellID";
    UITableViewCell *cell = 
    [tableView dequeueReusableCellWithIdentifier:unifiedID];

    if (!cell) 
    {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:unifiedID];  
    }

    NSString *providerNameString = [providerName objectAtIndex:indexPath.row];
    NSString *providerIdString = [providerId objectAtIndex:indexPath.row];
    cell.textLabel.text  = providerNameString;
    cell.detailTextLabel.text  = providerIdString;
    return cell;
}