Timer on NSDate

gistfile1.m

//
//  ViewController.m
//  gfhdsjkaryeuiw123
//
//  Created by Rex Fatahi on 6/6/14.
//  Copyright (c) 2014 aug2uag. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

{
    NSMutableDictionary* questionsJeapordy;
    NSMutableArray* questionsAllKeys;
    
    UIView* containerView;
    UILabel* containerViewLabel;
    
    BOOL isActive;
}

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
    
    questionsJeapordy = [NSMutableDictionary dictionary];
    questionsAllKeys = [NSMutableArray array];
    
    containerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.bounds.size.width, self.view.bounds.size.height)];
    [self.view addSubview:containerView];
    
    containerViewLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 44, self.view.bounds.size.width - 20, 160)];
    containerViewLabel.numberOfLines = 0;
    containerViewLabel.lineBreakMode = NSLineBreakByWordWrapping;
    [containerView addSubview:containerViewLabel];
    
    isActive = NO;
    
    // timer to check if 10 past the hour
    [NSTimer scheduledTimerWithTimeInterval: 10.0
                                     target: self
                                   selector:@selector(checkEvery10Minutes)
                                   userInfo: nil repeats:YES];
    
}

- (void)checkEvery10Minutes
{
    if (isActive) return;

    NSDate *date = [NSDate date];
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [calendar components:(NSMinuteCalendarUnit) fromDate:date];
    NSInteger minute = [components minute];
    
    if (minute % 10 == 0) {
        isActive = YES;
        [self makeQuestions];
    }
}

- (void)makeQuestions
{
    NSDictionary* dictionary1 = @{@"answer 1": @"question 1", @"answer 2": @"question 2", @"answer 3": @"question 3"};
    NSArray* allKeys1 = [dictionary1 allKeys];
    
    NSDictionary* dictionary2 = @{@"answer 1": @"question 1", @"answer 2": @"question 2", @"answer 3": @"question 3"};
    NSArray* allKeys2 = [dictionary2 allKeys];
    
    NSDictionary* dictionary3 = @{@"answer 1": @"question 1", @"answer 2": @"question 2", @"answer 3": @"question 3"};
    NSArray* allKeys3 = [dictionary3 allKeys];
    
    NSInteger randomInt = arc4random() % 3;
    
    NSString* randString1 = [allKeys1 objectAtIndex:randomInt];
    NSString* randString2 = [allKeys2 objectAtIndex:randomInt];
    NSString* randString3 = [allKeys3 objectAtIndex:randomInt];
    
    NSArray* arrayKeys = @[randString1, randString2, randString3];
    
    NSString* value1 = [dictionary1 valueForKey:randString1];
    NSString* value2 = [dictionary2 valueForKey:randString2];
    NSString* value3 = [dictionary3 valueForKey:randString3];
    
    NSArray* arrayValues = @[value1, value2, value3];
    
    [questionsJeapordy removeAllObjects];
    [questionsAllKeys removeAllObjects];
    questionsJeapordy = [NSMutableDictionary dictionaryWithObjects:arrayValues forKeys:arrayKeys];
    questionsAllKeys = (NSMutableArray *)[questionsJeapordy allKeys];
    
    [self showQuestion1];
    
    
}

- (void)showQuestion1
{
    NSString* key1 = [questionsAllKeys objectAtIndex:0];
    NSString* value1 = [questionsJeapordy valueForKey:key1];
    
    containerViewLabel.text = key1;
    
    [self.view bringSubviewToFront:containerView];
    
    [UIView animateWithDuration:0.3 animations:^{
        containerView.frame = self.view.bounds;
        
        int64_t delay = 60.0; // In seconds
        dispatch_time_t time = dispatch_time(DISPATCH_TIME_NOW, delay * NSEC_PER_SEC);
        dispatch_after(time, dispatch_get_main_queue(), ^(void){
            
            containerViewLabel.text = value1;
            
            [self performSelector:@selector(showQuestion2)
                       withObject:nil
                       afterDelay:10.0f];
            
        });
    }];
}

- (void)showQuestion2
{
    NSString* key2 = [questionsAllKeys objectAtIndex:1];
    NSString* value2 = [questionsJeapordy valueForKey:key2];
    
    containerViewLabel.text = key2;
    
    int64_t delay = 60.0; // In seconds
    dispatch_time_t time = dispatch_time(DISPATCH_TIME_NOW, delay * NSEC_PER_SEC);
    dispatch_after(time, dispatch_get_main_queue(), ^(void){
        
        containerViewLabel.text = value2;
        
        [self performSelector:@selector(showQuestion3)
                   withObject:nil
                   afterDelay:10.0f];
        
    });
}

- (void)showQuestion3
{
    NSString* key3 = [questionsAllKeys objectAtIndex:2];
    NSString* value3 = [questionsJeapordy valueForKey:key3];
    
    containerViewLabel.text = key3;
    
    int64_t delay = 60.0; // In seconds
    dispatch_time_t time = dispatch_time(DISPATCH_TIME_NOW, delay * NSEC_PER_SEC);
    dispatch_after(time, dispatch_get_main_queue(), ^(void){
        
        containerViewLabel.text = value3;
        
        int64_t delay2 = 15.0; // In seconds
        dispatch_time_t time2 = dispatch_time(DISPATCH_TIME_NOW, delay2 * NSEC_PER_SEC);
        dispatch_after(time2, dispatch_get_main_queue(), ^(void){
            
            [UIView animateWithDuration:0.3 animations:^{
                containerView.frame = CGRectMake(0, 0, self.view.bounds.size.width, self.view.bounds.size.height);
                isActive = NO;
            }];
        });
    });
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end