PerformSelectoronMainthread iosで呼び出しでオブジェクトをキャストオブジェクト
-
14-11-2019 - |
質問
を使った場合
[self performSelectorOnMainThread:@selector(uploadDidEnd:) withObject:foo
waitUntilDone:YES]
.
メソッド内で - (void)uploadDidend:(ID)送信者
どのオブジェクトが送信者ですか?呼び出しでFooはカスタムクラスですか?この送信者を私のオブジェクトに変換する方法は?
私はキャストしようとしていますが、私は
'-[_NSThreadPerformInfo CountY]: unrecognized selector sent to instance 0x52bbd0'
.
通知では、送信者からNSNotificationと通知にキャストを使用していますが、オブジェクトのプロパティがありますが、NSTHREADが見つかりませんでした。
ありがとう。
解決
You can think of:
[self performSelectorOnMainThread:@selector(uploadDidEnd:)
withObject:foo
waitUntilDone:YES]
as sort of the same as:
[self uploadDidEnd:foo];
Are you sure that's what you're trying to do?
If so: inside your uploadDidEnd:
implementation, you can cast foo to whatever object type it really is like so:
- (void)uploadDidEnd:(id)sender
{
FooClass *foo = (FooClass *)sender;
[foo doSomething]; // or whatever
}
他のヒント
The argument declared a
sender
is the only parameter passed to your method. performSelectorOnMainThread:withObject:waitUntilDone: passes its argument afterwithObject
to the selector to be performed, so yes, herefoo
will be passed to uploadDidEnd:Casting is not a solution. Objective-C is a dynamic language, so even if casting eliminates compiler warnings, the actual implementation of the object wouldn't change, so it naturally would not repond to messages.