Reload Section does not handle properly - objective-c

Question

I have the following implementation where I have title, and two buttons(titles are half and full) on the tablecell. When user selects and close the section and open it again, he only sees the default values of button title which is full rather than his selection.
I could able to see the following method (setHalfButton :indexPath
) is getting called during the reloading, but it does not have any effect.
Code and screenshots are follows.
- (void)selectItemAtIndexPath:(NSIndexPath *)indexPath setQuantity :(double) quantity {
NSMutableArray* array = [selectedRowsInSectionDictionary objectForKey:#(indexPath.section)];
if(array){
[array addObject:indexPath];
} else {
array = [NSMutableArray array];
[array addObject:indexPath];
[selectedRowsInSectionDictionary setObject:array forKey:#(indexPath.section)];
}
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"ComboCell";
ComboTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
{
cell = [[ComboTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
if([selectedRowsInSectionDictionary[#(indexPath.section)] containsObject: indexPath])
{
cell.accessoryType = UITableViewCellAccessoryCheckmark;
if(
comboItemsArray[indexPath.section].allComboItems[indexPath.row].pQuantity == 0.5)
{
// it comes here after reloading
[self setHalfButton:indexPath];
}
else
{
[self setFullButton:indexPath];
}
}
else
{
cell.accessoryType = UITableViewCellAccessoryNone;
cell.halfBtnOutlet.hidden = YES;
cell.fullBtnOutlet.hidden = YES;
}
cell.comboTitle.text =comboItemsArray[indexPath.section].allComboItems[indexPath.row].pName;
[cell.halfBtnOutlet addTarget:self action:#selector(halfBtnClicked:) forControlEvents:UIControlEventTouchUpInside];
[cell.fullBtnOutlet addTarget:self action:#selector(fullBtnClicked:) forControlEvents:UIControlEventTouchUpInside];
return cell;
}
-(void) setHalfButton : (NSIndexPath*)indexPath
{
ComboTableViewCell* cell = [comboTableView cellForRowAtIndexPath:indexPath];
[cell.halfBtnOutlet setTitleColor:[UIColor colorWithRed:0 green:102.0f/255.0f blue:0 alpha:1] forState:UIControlStateNormal];
[cell.fullBtnOutlet setTitleColor:[UIColor colorWithRed:0.5f green:0.5f blue:0.5f alpha:1] forState:UIControlStateNormal];
[cell.halfBtnOutlet.titleLabel setFont:[UIFont boldSystemFontOfSize:15.f]];
[cell.fullBtnOutlet.titleLabel setFont:[UIFont systemFontOfSize:15.f]];
}
-(void) setFullButton : (NSIndexPath*)indexPath
{
ComboTableViewCell* cell = [comboTableView cellForRowAtIndexPath:indexPath];
[cell.fullBtnOutlet setTitleColor:[UIColor colorWithRed:0 green:102.0f/255.0f blue:0 alpha:1] forState:UIControlStateNormal];
[cell.halfBtnOutlet setTitleColor:[UIColor colorWithRed:0.5f green:0.5f blue:0.5f alpha:1] forState:UIControlStateNormal];
[cell.fullBtnOutlet.titleLabel setFont:[UIFont boldSystemFontOfSize:15.f]];
[cell.halfBtnOutlet.titleLabel setFont:[UIFont systemFontOfSize:15.f]];
}

Answer 1

Your setHalfButton and setFullButton functions are being called from the cellForRowAtIndexPath: datasource method, but they are calling the cellForRowAtIndexPath: tableview method. Since you have not yet returned the cell from the former method, the latter method will return nil to cell, resulting in no visible update.
The setHalfButton and setFullButton methods should be in your ComboTableViewCell class:
-(void) setHalfButton
{
[self.halfBtnOutlet setTitleColor:[UIColor colorWithRed:0 green:102.0f/255.0f blue:0 alpha:1] forState:UIControlStateNormal];
[self.fullBtnOutlet setTitleColor:[UIColor colorWithRed:0.5f green:0.5f blue:0.5f alpha:1] forState:UIControlStateNormal];
[self.halfBtnOutlet.titleLabel setFont:[UIFont boldSystemFontOfSize:15.f]];
[self.fullBtnOutlet.titleLabel setFont:[UIFont systemFontOfSize:15.f]];
}
-(void) setFullButton
{
[self.fullBtnOutlet setTitleColor:[UIColor colorWithRed:0 green:102.0f/255.0f blue:0 alpha:1] forState:UIControlStateNormal];
[self.halfBtnOutlet setTitleColor:[UIColor colorWithRed:0.5f green:0.5f blue:0.5f alpha:1] forState:UIControlStateNormal];
[self.fullBtnOutlet.titleLabel setFont:[UIFont boldSystemFontOfSize:15.f]];
[self.halfBtnOutlet.titleLabel setFont:[UIFont systemFontOfSize:15.f]];
}
Also, you are adding the button action handlers each time you dequeue a cell, but you should only do this when you allocate a new cell. From a design point-of-view these button tap handlers should also be in your ComboTableViewCell class with a delegation pattern to notify the view controller that the half/full was changed.
At the very least it should look something like this:
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"ComboCell";
ComboTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
{
cell = [[ComboTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
[cell.halfBtnOutlet addTarget:self action:#selector(halfBtnClicked:) forControlEvents:UIControlEventTouchUpInside];
[cell.fullBtnOutlet addTarget:self action:#selector(fullBtnClicked:) forControlEvents:UIControlEventTouchUpInside];
}
if([selectedRowsInSectionDictionary[#(indexPath.section)] containsObject: indexPath])
{
cell.accessoryType = UITableViewCellAccessoryCheckmark;
if(
comboItemsArray[indexPath.section].allComboItems[indexPath.row].pQuantity == 0.5)
{
// it comes here after reloading
[cell setHalfButton];
}
else
{
[cell setFullButton];
}
}
else
{
cell.accessoryType = UITableViewCellAccessoryNone;
cell.halfBtnOutlet.hidden = YES;
cell.fullBtnOutlet.hidden = YES;
}
cell.comboTitle.text =comboItemsArray[indexPath.section].allComboItems[indexPath.row].pName;
return cell;
}