init和awakeFromNib [英] init and awakeFromNib

问题描述

我想明白为什么如果我尝试设置值（即setAlphaValue或setTitle）对象（如NSButton）在init方法没有什么发生，但如果我调用setter函数在awakeFromNib它工作正常。

  @interface appController：NSObject {
 NSButton * btn; 
} 
 @end; 
 
 @implementation appController 
  - （void）awakeFromNib {
 // it works 
 [btn setTitle：@My title]; 
} 
 
  - （id）init {
 self = [super init]; 
 if（self）{
 //它不工作
 [btn setTitle：@My title]; 
} 
} 
 @end 
  

解决方案< 之后 之后设置 -init code>。如果你想访问插座，你需要在 -awakeFromNib 或者在插座设置后执行的另一个方法（例如 - [NSWindowController windowDidLoad

b
1. 分配/初始化nib文件中的对象，接收 -init ， -initWithFrame： -initWithCoder：


2. 重新建立所有连接。这包括操作，发布商和绑定。


3. -awakeFromNib 发送到接口对象，文件所有者和代理对象。 li>
   

您可以在资源编程指南。

I'd like understand why if i try to set value (I.e. setAlphaValue or setTitle) for an object (like a NSButton) in init method nothing happen, but if i call setter function in awakeFromNib it works correctly.

@interface appController : NSObject {
    NSButton *btn;
}
@end;

@implementation appController
-(void)awakeFromNib {
   //it works
   [btn setTitle:@"My title"];
}

-(id)init { 
    self = [super init];
    if(self){
        //it doesn't works
        [btn setTitle:@"My title"];
    }
}
@end

解决方案

Outlets are set after -init and before -awakeFromNib. If you want to access outlets, you need to do that in -awakeFromNib or another method that’s executed after the outlets are set (e.g. -[NSWindowController windowDidLoad]).

When a nib file is loaded:

1. Objects in the nib file are allocated/initialised, receiving either -init, -initWithFrame:, or -initWithCoder:
2. All connections are reestablished. This includes actions, outlets, and bindings.
3. -awakeFromNib is sent to interface objects, file’s owner, and proxy objects.

You can read more about the nib loading process in the Resource Programming Guide.

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