UIPickerView titleForRow not called - View with two pickers

[Craftpaper]

Hi!
I'm currently working on a single View with two pickerViews.
I've found something like :

- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component
{
if([thePickerView isEqual:pickerView ]){ 
    return [arrayNo count];
}
else if([thePickerView isEqual:pickerView2]){       
    return [arrayRootNote count];
}

else{
    return 0;
}

}  
- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
 if([thePickerView isEqual:pickerView])
 { 
   return [arrayNo objectAtIndex:row];
}
else if([thePickerView isEqual:pickerView2]){       
    return [arrayRootNote objectAtIndex:row];
}

else{
    return [arrayRootNote objectAtIndex:row];
}

 NSLog(@"I am a called method"); 
}

What I want is to change the title of each picker (populated by the two NSMutableArrays). The problem is that the two pickers are showing the "ArrayNo" of the pickerView.

I've found with the debugger (and the NSLog) that the method titleForRow is not called at all.
Any idea? Thanks in advance

Séraphin

[Craftpaper]

the delegate is set with

pickerView.delegate = self;
pickerView2.delegate = self;

And everything is connected with IB!