在多视图应用程序中设置类实例（Objective C） [英] Setting up class instances in a multi view app (Objective C)

问题描述

我是Objective C，Xcode等等的新手。感谢您的帮助，阅读这个论坛，我做了一些正确的方向，但只有在单一视图应用程序。

现在我有我的故事板views：

（FirstViewController.h / m）
（SecondViewController.h / m）

我还创建了一个Objective C类，用于从这两个视图接收数据。

第一次，在FirstViewController中，我有一个IBA ACTION。

按下按钮时：

  controllo * 
 control = [[controllo alloc] init]; 
  

然后我使用属性设置控制实例..和It工作。 >

现在controllo（控制）的同一个实例应该从我的SecondViewClass接收数据，但是我无法访问它，即使第一个视图的按钮（IBA ACTION）在传递到第二个视图之前按下。

您能告诉我我的项目中需要的所有视图是如何访问的？

感谢！

解决方案

将所有变量放入类中，通过singleton模式访问类，并将类头导入前缀.pch文件

示例：

GlobalClass.h

  #import< Foundation / Foundation.h> 
 
 @interface GlobalClass：NSObject 
 
 @property（nonatomic，strong）NSString * globalString; 
 @property（nonatomic，strong）NSNumber * globalNumber; 
 
 +（GlobalClass *）sharedClass; 
 
  - （void）methodA; 
 
 @end 
  

和GlobalClass.m

  #importGlobalClass.h
 
 @implementation GlobalClass 
 
 +（GlobalClass *）sharedClass {
 
 static GlobalClass * _sharedClass = nil; 
 
 static dispatch_once_t oncePredicate; 
 
 dispatch_once（& oncePredicate，^ {
 _sharedClass = [[GlobalClass alloc] init]; 
}）; 
 
 return _sharedClass; 
} 
 
  - （id）init {
 self = [super init]; 
 if（self）{
 
 //这里的初始化变量
 
} 
 
 return self; 
} 
 
  - （void）methodA {
 
 //在这里做一些事情
 NSLog（@this is methodA called）; 
 
} 
 
 @end 
  

您的.pch文件中的支持文件

  #importGlobalClass.h
  
 
 
 
现在你可以使用任何类来访问全局类变量：
  [GlobalClass sharedClass] .globalString = @这是一个全局字符串; 
  
您还可以使用以下方法访问该方法：
  [GlobalClass sharedClass] methodA]; 
  
 
I am a newbie in Objective C, Xcode and so on. Thanks to your help, reading this forum, i did some steps in the right direction, but only in a "Single View Application".

Now I have in my storyboard two views:

(FirstViewController.h / m)
(SecondViewController.h /m)

I also created an Objective C class whom is meant to receive data from those two views.

At first time, in the FirstViewController i had an IBA ACTION.

When a button was pressed:
controllo *control;
control = [[controllo alloc] init];
and then i use to set "control" instances using properties .. and It worked.

Now The same instance of "controllo" (control) should receive data even from my SecondViewClass, but I cannot access to it, even if the button of the first view (IBA ACTION) is pressed BEFORE passing to the second view. 

Could you please show me how have a class accessible from all the views I need in my project?

Thanks!
解决方案
Put all your variables inside a class, access the class via singleton pattern, and import the class header into the prefix.pch file

example :

GlobalClass.h
#import <Foundation/Foundation.h>

@interface GlobalClass : NSObject

@property (nonatomic, strong) NSString *globalString;
@property (nonatomic, strong) NSNumber *globalNumber;

+ (GlobalClass*) sharedClass;

- (void) methodA;

@end
and in GlobalClass.m
#import "GlobalClass.h"

@implementation GlobalClass

+ (GlobalClass *)sharedClass {

 static GlobalClass *_sharedClass = nil;

 static dispatch_once_t oncePredicate;

 dispatch_once(&oncePredicate, ^{
     _sharedClass = [[GlobalClass alloc] init];
 });

 return _sharedClass;
}

- (id)init {
    self = [super init];
    if (self) {

    //init variable here

    }

    return self;
}

- (void) methodA {

   //do something here
   NSLog(@"this is methodA called");

}

@end
put this inside your .pch file in supporting files
#import "GlobalClass.h"
now you can access the global class variable from any class, by using :
[GlobalClass sharedClass].globalString = @"this is a global string";
you can also access the method, by using :
[GlobalClass sharedClass] methodA];


                        
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