Segmented control to switch views within view controller [duplicate] - ios

Question

This problem is driving me crazy. I'm trying to change the viewController when the user changes the selected "tab" of the segmented control. I've spent a couple hours researching and haven't been able to find an answer that works or is done through storyboard.
It really bother me since setting a tab application is so easy, but trying to use the segmented control like the tab application is just not working. I already know how to detect which index is selected in the segmented control. How can I achieve this?
Thank you very much.

Answer 1

NOTE: Answer updated with view controller containment code for iOS 5+ including #interface section
In an app of mine, I have a view controller with a Segment Control in the Navigation Bar and clicking on the "tabs" switches view controllers. The basic idea is to have an array of view controllers and switch between them using the Segment Index (and the indexDidChangeForSegmentedControl IBAction.
Example code (iOS 5 or later) from my app (this is for 2 view controllers but it's trivially extended to multiple view controllers); the code is slightly longer than for iOS 4 but will keep the object graph intact. Also, it uses ARC:
#interface MyViewController ()
// Segmented control to switch view controllers
#property (weak, nonatomic) IBOutlet UISegmentedControl *switchViewControllers;
// Array of view controllers to switch between
#property (nonatomic, copy) NSArray *allViewControllers;
// Currently selected view controller
#property (nonatomic, strong) UIViewController *currentViewController;
#end
#implementation UpdateScoreViewController
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
[super viewDidLoad];
// Create the score view controller
ViewControllerA *vcA = [self.storyboard instantiateViewControllerWithIdentifier:#"ViewControllerA"];
// Create the penalty view controller
ViewControllerB *vcB = [self.storyboard instantiateViewControllerWithIdentifier:#"ViewControllerB"];
// Add A and B view controllers to the array
self.allViewControllers = [[NSArray alloc] initWithObjects:vcA, vcB, nil];
// Ensure a view controller is loaded
self.switchViewControllers.selectedSegmentIndex = 0;
[self cycleFromViewController:self.currentViewController toViewController:[self.allViewControllers objectAtIndex:self.switchViewControllers.selectedSegmentIndex]];
}
#pragma mark - View controller switching and saving
- (void)cycleFromViewController:(UIViewController*)oldVC toViewController:(UIViewController*)newVC {
// Do nothing if we are attempting to swap to the same view controller
if (newVC == oldVC) return;
// Check the newVC is non-nil otherwise expect a crash: NSInvalidArgumentException
if (newVC) {
// Set the new view controller frame (in this case to be the size of the available screen bounds)
// Calulate any other frame animations here (e.g. for the oldVC)
newVC.view.frame = CGRectMake(CGRectGetMinX(self.view.bounds), CGRectGetMinY(self.view.bounds), CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds));
// Check the oldVC is non-nil otherwise expect a crash: NSInvalidArgumentException
if (oldVC) {
// Start both the view controller transitions
[oldVC willMoveToParentViewController:nil];
[self addChildViewController:newVC];
// Swap the view controllers
// No frame animations in this code but these would go in the animations block
[self transitionFromViewController:oldVC
toViewController:newVC
duration:0.25
options:UIViewAnimationOptionLayoutSubviews
animations:^{}
completion:^(BOOL finished) {
// Finish both the view controller transitions
[oldVC removeFromParentViewController];
[newVC didMoveToParentViewController:self];
// Store a reference to the current controller
self.currentViewController = newVC;
}];
} else {
// Otherwise we are adding a view controller for the first time
// Start the view controller transition
[self addChildViewController:newVC];
// Add the new view controller view to the ciew hierarchy
[self.view addSubview:newVC.view];
// End the view controller transition
[newVC didMoveToParentViewController:self];
// Store a reference to the current controller
self.currentViewController = newVC;
}
}
}
- (IBAction)indexDidChangeForSegmentedControl:(UISegmentedControl *)sender {
NSUInteger index = sender.selectedSegmentIndex;
if (UISegmentedControlNoSegment != index) {
UIViewController *incomingViewController = [self.allViewControllers objectAtIndex:index];
[self cycleFromViewController:self.currentViewController toViewController:incomingViewController];
}
}
#end
Original example (iOS 4 or before):
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
[super viewDidLoad];
// Create the score view controller
AddHandScoreViewController *score = [self.storyboard instantiateViewControllerWithIdentifier:#"AddHandScore"];
// Create the penalty view controller
AddHandPenaltyViewController *penalty = [self.storyboard instantiateViewControllerWithIdentifier:#"AddHandPenalty"];
// Add Score and Penalty view controllers to the array
self.allViewControllers = [[NSArray alloc] initWithObjects:score, penalty, nil];
// Ensure the Score controller is loaded
self.switchViewControllers.selectedSegmentIndex = 0;
[self switchToController:[self.allViewControllers objectAtIndex:self.switchViewControllers.selectedSegmentIndex]];
}
#pragma mark - View controller switching and saving
- (void)switchToController:(UIViewController *)newVC
{
if (newVC) {
// Do nothing if we are in the same controller
if (newVC == self.currentViewController) return;
// Remove the current controller if we are loaded and shown
if([self.currentViewController isViewLoaded]) [self.currentViewController.view removeFromSuperview];
// Resize the new view controller
newVC.view.frame = CGRectMake(CGRectGetMinX(self.view.bounds), CGRectGetMinY(self.view.bounds), CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds));
// Add the new controller
[self.view addSubview:newVC.view];
// Store a reference to the current controller
self.currentViewController = newVC;
}
}
- (IBAction)indexDidChangeForSegmentedControl:(UISegmentedControl *)sender {
NSUInteger index = sender.selectedSegmentIndex;
if (UISegmentedControlNoSegment != index) {
UIViewController *incomingViewController = [self.allViewControllers objectAtIndex:index];
[self switchToController:incomingViewController];
}
}

Answer 2

I'd say it's much simpler to change subviews within a UIViewController, you can set up your subviews in your storyboards and hook them up with IBOulets in your controller you can set the hidden property of your views to YES or NO depending on the control that was clicked.
Now, if you use #Robotic Cat's approach which is also a good solution you can have a little more modularity in how your app works, considering you'd have to place all your logic in one controller using the solution I presented.

Answer 3

UISegmentedControl is a little different in that it doesn't have a delegate protocol, you have to use the "add target" style. In your case what you want to do is add a target to be notified when the UISegmentedControl changes (which is likely the parent view controller), and then that target can deal with the tab switching.
For example:
[self.mainSegmentedControl addTarget:self action:#selector(changedSegmentedControl:) forControlEvents:UIControlEventValueChanged];
In this example, the code is being invoked from some view/controller that has access to the variable for the segmented control. We add ourself to get the changedSegmentedControl: method invoked.
Then you would have another method like so:
- (void)changedSegmentedControl:(id)sender
{
UISegmentedControl *ctl = sender;
NSLog(#"Changed value of segmented control to %d", ctl.selectedSegmentIndex);
// Code to change View Controller goes here
}
Note: this is untested code written from memory -- please consult the docs accordingly.

Answer 4

Take a look at this pod: https://github.com/xmartlabs/XLMailBoxContainer. It makes the UI animation among the view controllers. These view controller can extend UITableViewController or any other view controller.
I hope this help you!