Value passing through an example in IOS

Value passing through an example in IOS

In IOS apps, different views and apps often share values and variables. There are several ways to achieve this:

1. extern Method

2. Singleton Mode

3. delegate Mode

The Singleton mode only has one instance as its name implies. It ensures that a class has only one instance and instantiate it and provides the instance to the entire system. It is often used for application-level shared resource control. This mode is frequently used. You can use a singleton class to transfer parameters between different views.

# Import
 
  
@ Interface Session: NSObject @ property (strong, nonatomic) NSString * singleValue; // The singleValue method + (Session *) GetInstance; @ end
 

# Import "Session. h "@ implementation Session // single instance object static Session * instance; // Single instance + (Session *) GetInstance {@ synchronized (self) {if (instance = nil) {instance = [[self alloc] init] ;}} return instance ;}- (id) init {if (self = [super init]) {self. singleValue = [[NSString alloc] init];} return self ;}@ end

Then, import the singleton class to use the singleton class.

Session * session = [Session GetInstance];

Session. singleValue = @ "Amazing! ";

NSString * value = session. singleValue;