Expand custom section cells in UITableView

Question

1)Here is the problem.I am designing an iOS app where I need to show the contents of a cell on clicking on a section(my custom sections).I have 2 such sections.Now the logic that I used here is that I'm hiding a cell until I click on its section.But the problem that I'm facing in this regard is that when the 1st cell expands,it overlaps with the second section for a fraction of a second.The reason for that is the following code:

    //call to UITableView Delegate method 'cellForRowAtIndexPath:'
    [tableView beginUpdates];
    //some code
    [tableView endUpdates];

Now I'm calling 'cellForRowAtIndexPath:' to unhide my cell but it gets executed after the updates.

2)Second logic that I thought about was that I set the height for each row as 0 at the start.But it ain't helping as the designs of both the custom cells overlap with each other.

What should I do now?

Answer 1

Use Following code for expandable Cell into UITableView

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";   
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }
    cell.textLabel.text=[[self.arForTable objectAtIndex:indexPath.row] valueForKey:@"name"];
    [cell setIndentationLevel:[[[self.arForTable objectAtIndex:indexPath.row] valueForKey:@"level"] intValue]];    
    return cell;
}

code for expanding & collapsing rows – TableView DidSelectRow Method

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [tableView deselectRowAtIndexPath:indexPath animated:YES];
    NSDictionary *d=[self.arForTable objectAtIndex:indexPath.row];
    if([d valueForKey:@"Objects"]) {
        NSArray *ar=[d valueForKey:@"Objects"];
        BOOL isAlreadyInserted=NO;
        for(NSDictionary *dInner in ar ){
            NSInteger index=[self.arForTable indexOfObjectIdenticalTo:dInner];
            isAlreadyInserted=(index>0 && index!=NSIntegerMax);
            if(isAlreadyInserted) break; 
        }
        if(isAlreadyInserted) {
            [self miniMizeThisRows:ar];
        } else {        
            NSUInteger count=indexPath.row+1;
            NSMutableArray *arCells=[NSMutableArray array];
            for(NSDictionary *dInner in ar ) {
                [arCells addObject:[NSIndexPath indexPathForRow:count inSection:0]];
                [self.arForTable insertObject:dInner atIndex:count++];
            }
            [tableView insertRowsAtIndexPaths:arCells withRowAnimation:UITableViewRowAnimationLeft];
        }
    }
}

A Method which will help to minimize & maximize/expand-collapse rows.

-(void)miniMizeThisRows:(NSArray*)ar{
    for(NSDictionary *dInner in ar ) {
        NSUInteger indexToRemove=[self.arForTable indexOfObjectIdenticalTo:dInner];        
        NSArray *arInner=[dInner valueForKey:@"Objects"];
        if(arInner && [arInner count]>0){
            [self miniMizeThisRows:arInner];
        }
        if([self.arForTable indexOfObjectIdenticalTo:dInner]!=NSNotFound) {
            [self.arForTable removeObjectIdenticalTo:dInner];
            [self.tableView deleteRowsAtIndexPaths:
              [NSArray arrayWithObject:[NSIndexPath indexPathForRow:indexToRemove inSection:0]]
                      withRowAnimation:UITableViewRowAnimationRight];
        }
    }
}

Download code from here