/*

     File: ParentViewController.m

 Abstract: The sample's primary/parent view controller

  Version: 1.1

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#import "ParentViewController.h"

#import "Child1ViewController.h"

#import "Child2ViewController.h"

@interface ParentViewController ()

@property (nonatomic, strong) IBOutlet UIView *placeholderView;

@property (nonatomic, strong) IBOutlet UISegmentedControl *segControl;

@property (nonatomic, strong) Child1ViewController *child1;

@property (nonatomic, strong) Child2ViewController *child2;

@end

@implementation ParentViewController

- (void)viewDidLoad

{

    [super viewDidLoad];

    self.navigationController.navigationBar.translucent = NO;

    // create and add our two children view controllers from our storyboard

    self.child1 = [self.storyboard instantiateViewControllerWithIdentifier:@"child1"];

    [self addChildViewController:self.child1];

    [self.child1 didMoveToParentViewController:self];

    self.child2 = [self.storyboard instantiateViewControllerWithIdentifier:@"child2"];

    [self addChildViewController:self.child2];

    [self.child2 didMoveToParentViewController:self];

    // by default child1 should be visible

    // (note that later, UIStateRestoriation might change this)

    //

    [self addChild:self.child1 withChildToRemove:nil];

}

- (void)addChild:(UIViewController *)childToAdd withChildToRemove:(UIViewController *)childToRemove

{

    assert(childToAdd != nil);

    if (childToRemove != nil)

    {

        [childToRemove.view removeFromSuperview];

    }

    // match the child size to its parent

    CGRect frame = childToAdd.view.frame;

    frame.size.height = CGRectGetHeight(self.placeholderView.frame);

    frame.size.width = CGRectGetWidth(self.placeholderView.frame);

    childToAdd.view.frame = frame;

    [self.placeholderView addSubview:childToAdd.view];

}

// user tapped on the segmented control to choose which child is to be visible

- (IBAction)segmentControlAction:(id)sender

{

    UISegmentedControl *segControl = (UISegmentedControl *)sender;

    UIViewController *childToAdd, *childToRemove;

    childToAdd = (segControl.selectedSegmentIndex == 0) ? self.child1 : self.child2;

    childToRemove = (segControl.selectedSegmentIndex == 0) ? self.child2 : self.child1;

    [self addChild:childToAdd withChildToRemove:childToRemove];

}

#pragma mark - UIStateRestoration

// encodeRestorableStateWithCoder is called when the app is suspended to the background

- (void)encodeRestorableStateWithCoder:(NSCoder *)coder

{

    NSLog(@"ParentViewController: encodeRestorableStateWithCoder");

    // remember our children view controllers

    [coder encodeObject:self.child1 forKey:@"child1"];

    [coder encodeObject:self.child2 forKey:@"child2"];

    // remember the segmented control state

    [coder encodeInteger:self.segControl.selectedSegmentIndex forKey:@"selectedIndex"];

    [super encodeRestorableStateWithCoder:coder];

}

// decodeRestorableStateWithCoder is called when the app is re-launched

- (void)decodeRestorableStateWithCoder:(NSCoder *)coder

{

    NSLog(@"ParentViewController: decodeRestorableStateWithCoder");

    // find out which child was the current visible view controller

    self.segControl.selectedSegmentIndex = [coder decodeIntegerForKey:@"selectedIndex"];

    // call our segmented control to set the right visible child

    // (note that we already previously have already loaded both children view controllers in viewDidLoad)

    //

    [self segmentControlAction:self.segControl];

    [super decodeRestorableStateWithCoder:coder];

}

@end