If I assign a signal to a property of a control:
RAC(self.loginButton.enabled) = [RACSignal
combineLatest:@[
self.usernameTextField.rac_textSignal,
self.passwordTextField.rac_textSignal
] reduce:^(NSString* username, NSString* password) {
return @(username.length > 0 && password.length > 0);
}];
But then wanted to assign a different RACSignal to enabled, how can I clear any existing one before doing so?
If I try and set it a second time, I get an exception like the following:
2013-10-29 16:54:50.623 myApp[3688:c07] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Signal <RACSignal: 0x975e9e0> name: +combineLatest: (
"<RACSignal: 0x975d600> name: <UITextField: 0x10f2c420> -rac_textSignal",
"<RACSignal: 0x975de30> name: <UITextField: 0x10f306e0> -rac_textSignal"
) reduce: is already bound to key path "self.loginButton.enabled" on object <LoginViewController: 0x10f264e0>, adding signal <RACSignal: 0x9763500> name: +combineLatest: (
"<RACSignal: 0x97624f0> name: <UITextField: 0x10f2c420> -rac_textSignal",
"<RACSignal: 0x97629e0> name: <UITextField: 0x10f306e0> -rac_textSignal"
) reduce: is undefined behavior'