How to update the table in the MasterViewController - xcode

Question

I am using a Master-Detail template.
I have a segmented control in the detail view and I have set the MasterViewController as the delegate.
This enables me to give the user choices.
I know the segmented control is working and passing the choices to the MVC.
I want each choice to trigger a new set of data which can then be loaded into the table view in the MasterViewController.
My problem is that I cannot then find a way to update the data in the table view.

Answer 1

You can use an instance variable declared in MasterViewController to be updated while UISegmentedControl changes. Based on that, When you come back to the MasterViewController; use its viewWillAppear to [tableView reloadData]
Tell me if I am getting your question wrong.
EDIT:
Take an integer name it segmentIndex; update as and when Segment gets changed. Based on the value of segmentIndex load the dataSource needed to be displayed on UITableView of your MasterViewController
EDIT 2:
When UISegmentedControl's value changes, put mvc.segmentIndex = (currentValueOfYourSegmentedControl);
Then in MasterViewController's viewWillAppear
switch (self.segmentIndex)
{
case 0:
// Set Datasource for First Choice.
break;
case 0:
// Set Datasource for Second Choice.
break;
case 0:
// Set Datasource for Third Choice.... and so on...
break;
default:
// Default Behavior
break;
}
Hope You Get My Point.

Answer 2

If it was me I would use notifications instead of delegates. i.e Detect the segmentedControl value change using valueChanged inside the detailViewController and then post an NSNotification from your detailViewcontroller which your masterViewController receives.
Easiest way is:
[[NSNotificationCenter defaultCenter] postNotificationName:#"segmentOneChosen" object:nil userInfo:nil];
Have you masterViewController register for this notification:
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(segmentOneChosen) name:#"segmentOneChosen" object:nil];
It would be better still to pass the chosen value along with the notification so you don't need a separate notification for each segment.
!! untested code:
NSArray *keys = [NSArray arrayWithObjects:#"segmentChosen", nil];
NSArray *objects = [NSArray arrayWithObjects:[NSNumber numberWithInt:self.topicsChoiceSegControl.selectedSegmentIndex], nil];
NSDictionary * dict = [NSDictionary dictionaryWithObjects:objects forKeys:keys];
[[NSNotificationCenter defaultCenter] postNotificationName:#"segmentChosen" object:nil userInfo:dict];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(segmentChosen:) name:#"segmentChosen" object:nil];
-(void) segmentChosen:(NSNotification *)notification {
NSNumber *segmentChosenNum = [[notification userInfo] valueForKey:#"segmentChosen"];
}
I know this doesn't answer your question per se, but it does provide an alternative solution to the problem you are trying to overcome.