Trait objc::Message

source · 
pub unsafe trait Message {
    // Provided methods
    unsafe fn send_message<A, R>(
        &self,
        sel: Sel,
        args: A
    ) -> Result<R, MessageError>
       where Self: Sized,
             A: MessageArguments,
             R: Any { ... }
    fn verify_message<A, R>(&self, sel: Sel) -> Result<(), MessageError>
       where Self: Sized,
             A: EncodeArguments,
             R: Encode { ... }
}
Expand description

Types that may be sent Objective-C messages. For example: objects, classes, and blocks.

Provided Methods§

source

unsafe fn send_message<A, R>( &self, sel: Sel, args: A ) -> Result<R, MessageError>where Self: Sized, A: MessageArguments, R: Any,

Sends a message to self with the given selector and arguments.

The correct version of objc_msgSend will be chosen based on the return type. For more information, see Apple’s documentation: https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ObjCRuntimeRef/index.html#//apple_ref/doc/uid/TP40001418-CH1g-88778

If the selector is known at compile-time, it is recommended to use the msg_send! macro rather than this method.

source

fn verify_message<A, R>(&self, sel: Sel) -> Result<(), MessageError>where Self: Sized, A: EncodeArguments, R: Encode,

Verifies that the argument and return types match the encoding of the method for the given selector.

This will look up the encoding of the method for the given selector, sel, and return a MessageError if any encodings differ for the arguments A and return type R.

Example
let obj: &Object;
let sel = sel!(isKindOfClass:);
// Verify isKindOfClass: takes one Class and returns a BOOL
let result = obj.verify_message::<(&Class,), BOOL>(sel);
assert!(result.is_ok());

Implementors§