Using a variable in every view controller how? - ios

Question

As the title says I need to use same variable in different viewcontllers.
Until this day when I want to use a variable in different viewcontllers I send that specific variable via segues but I don't think that is a good way it requires program to carry variables from one point to another and if there are 5 view controllers this can be messy.
When I search the internet I always found codes about sending variables from one to another by segues and I have read something about global variables but I am not sure that is the one.
Example:(3 view controller program)
User opens the app and at the first viewcontller clicks ''3'' button ( or 1-2-3-4-5) the int x variable become x=3.Later he choses to go on.
Second view controller writes on screen x+x user clicks to 3 viewcontroller.(code is written inside)
Third view controller writes on screen x*x user clicks to 3 view controller.(code is written inside)
As you can see I have used that x variable in different view controllers and please remember I don't want to transfer variables between them so any ideas for that and is this kind of a thing possible.
My Guess using pointers or taking some space in memory my malloc and pointing it from anotherviewcontroller might work.
Answer:As stated in answer below there are two ways this one is suitable for me.
1 view controller
int x =5;
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:[NSNumber numberWithInt:x] forKey:#"keyForTheValue"];
[defaults synchronize];
2 view controller
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
int y = [[defaults objectForKey:#"keyForTheValue"] intValue];
intyazi.text = [[NSString alloc] initWithFormat:#"%d", y];

Answer 1

There are several ways to avoid passing the variable from ViewController to ViewController.
But keep in mind, that in some cases it's better to pass it.
Singleton Datacontainer
One way would be using a Singleton Datacontainer:
Header (Threadsafe implementation):
#import <foundation/Foundation.h>
#interface MyManager : NSObject {
NSInteger *someProperty;
}
#property (nonatomic, retain) NSInteger *someProperty;
+ (id)sharedManager;
#end
Implementation:
#import "MyManager.h"
#implementation MyManager
#synthesize someProperty;
#pragma mark Singleton Methods
+ (id)sharedManager {
static MyManager *sharedMyManager = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
sharedMyManager = [[self alloc] init];
});
return sharedMyManager;
}
- (id)init {
if (self = [super init]) {
// Default value
someProperty = #0;
}
return self;
}
#end
NSUserDefaults
Or you could use NSUserDefaults. Which does store the value persistent in the user directory and is also available on the next startup.
Storing a value:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:[NSNumber numberWithInt:yourIntValue] forKey:#"keyForTheValue"];
[defaults synchronize];
Loading the value:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
int yourIntValue = [[defaults objectForKey:#"keyForTheValue"] intValue];