Accessing Unknown 'ID' class method-Objective C

RS232MsgGetEventDescriptions.h:

#define DECLARE_RS232_NEWMSG(ClassID)\
enum                                 \
{                                    \
ID = ClassID                         \
};                                   \

@interface RS232MsgGetEventDescriptions : RS232Msg
{

}
@end

RS232MsgGetEventDescriptions.m

@implementation RS232MsgGetEventDescriptions

 DECLARE_RS232_NEWMSG(RM_GET_EVENT_DESCRIPTIONS);
@end

EventLogs.m

-(void)event
{
service = [CServiceAppDlg alloc];
if ([service:(R开发者_如何学GoEMOTE_MESSAGE_ID)RS232MsgGetEventDescriptions.ID withEvent:pEvent]) 
 {
    NSLog(@"Get Event descriptions!!");
 }
}

I'm getting an error like "Accessing Unknown 'ID' class method" I should not modify the definition here.How to pass the ID.I am going to call different descriptions ID in the same way so is this declaration of ID.

---

The reason why you are getting a Accessing Unknown 'ID' class method error message is because you have not declared a method called ID in your class RS232MsgGetEventDescriptions.

When you say RS232MsgGetEventDescriptions.ID in your code, you are calling the property ID of object RS232MsgGetEventDescriptions, which is equivalent to [RS232MsgGetEventDescriptions ID]. However, RS232MsgGetEventDescriptions is not an object, but a class and you don't have a class method called + (REMOTE_MESSAGE_ID)ID in your class specification (you don't have it declared on the interface or implemented on the class implementation).

I would also like to point out that it is bad practice to use the dot notation for something other than a property. Since classes cannot have @properties (these are for objects) you should call this method using standard Objective-C messaging notation [RS232MsgGetEventDescriptions ID].

Xcode will still allow you to write object.methodName to call methods with no parameters, and object.methodName = value for methods that take 1 parameter. Because they are interpreted as follows:

object.methodName;  // Becomes [object methodName]
object.methodName = value;    // Becomes [object setMethodName:value]