UITableView Delegate Method not getting called? - ios

Question

I' m trying to extract the UITableView Delegate method into a base class called BaseTableProvider
//BaseTableProvider.h
#protocol RSTableProviderProtocol <NSObject>
- (void)cellDidPress:(NSIndexPath *) atIndexPath;
#optional
- (void)cellNeedsDelete:(NSIndexPath *) atIndexPath;
#end
#interface RSBaseTableProvider : NSObject <UITableViewDelegate, UITableViewDataSource>
#property (nonatomic, strong) NSMutableArray *dataSource;
#property (nonatomic, weak) id<RSTableProviderProtocol> delegate;
#end
//BaseTableProvider.m
#implementation RSBaseTableProvider
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return 0;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
UITableViewCell *cell = [[UITableViewCell alloc]init];
return cell;
}
#end
And then I create a subclass of BaseTableProvider, and override two UITableViewDelegate Method in the subclass
//RSFeedListTableProvider.h
#interface RSFeedListTableProvider : RSBaseTableProvider
#end
//RSFeedListTableProvider.m
#implementation RSFeedListTableProvider
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
return [self.dataSource count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
RSFeedCell *cell = (RSFeedCell *)[tableView dequeueReusableCellWithIdentifier:kFeedCell];
if(cell == nil){
cell = [[RSFeedCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:kFeedCell];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
Feed *feed = (Feed *)self.dataSource[indexPath.row];
if (feed != nil) {
cell.titleText = feed.title;
cell.subTitleText = feed.summary;
}
return cell;
}
#end
I initialized the ListTablerProvider in a ViewController.
//RSFeedListViewController.m
#implementation RSFeedListViewController
- (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{
_feedListView = [[RSFeedListView alloc] init];
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
_provider = [[RSFeedListTableProvider alloc] init];
_provider.delegate = self;
return self;
}
#pragma mark -- Life Cycle
- (void)loadView{
RSFeedListView *aView = [[RSFeedListView alloc] initWithFrame:[UIScreen mainScreen].bounds];
self.feedListView = aView;
self.view = aView;
self.feedListView.tableView.delegate = _provider;
self.feedListView.tableView.dataSource = _provider;
}
But I can't see the cell built on the screen.I debuged the code found that UITableView Delegate Method in RSFeedListTableProvider was not called.Any one can help me?Thanks!

Answer 1

I think you did not implement the numberOfRowsInSection datasource method in your subclass RSFeedListTableProvider. So it will invoke the super class implementation
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return 0;
}
and there you are returning zero, so cellForRowAtIndexPath in your subclass never will be called.
Solution is implement numberOfRowsInSection in subclass and return proper count

Answer 2

Maybe you are inherited NSObject instead UITableViewController! And you need to create property UITableView *tableView, and connect to your UITableViewController dataSource and delegate.