GitHub地址：ReactiveCocoa
RAC.png
一、响应式编程就是实时响应某个事件
// 创建信号
RACSignal *signal = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber> _Nonnull subscriber) {
NSLog(@"Hello");
// 发送信号
[subscriber sendNext:@"This is RAC"];
return nil;
}];
// 订阅信号
[signal subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
二、RAC很强大，一行代码搞定以前的事件监听
举几个实际使用案例
1. TargetAction转Block
①UITextField(实时监听输入框内容)
[[self.textField rac_textSignal] subscribeNext:^(NSString * _Nullable x) {
NSLog(@"%@", x);
}];
②UITextField(实时监听多个输入框内容)
[[RACSignal combineLatest:@[self.nameTextField.rac_textSignal, self.pwdTextField.rac_textSignal]] subscribeNext:^(RACTuple * _Nullable x) {
NSLog(@"name : %@, pwd : %@", x.first, x.second);
}];
[[[RACSignal combineLatest:@[self.nameTextField.rac_textSignal, self.pwdTextField.rac_textSignal]] reduceEach:^id _Nullable(NSString *name, NSString *pwd) {
return @(name.length && pwd.length);
}] subscribeNext:^(id _Nullable x) {
NSLog(@"%zd", [x boolValue]);
}];
③UIButton(Button点击事件)
[[self.button rac_signalForControlEvents:(UIControlEventTouchUpInside)] subscribeNext:^(__kindof UIControl * _Nullable x) {
NSLog(@"%@",x);
}];
2. 通知转Block
[[[NSNotificationCenter defaultCenter] rac_addObserverForName:UIApplicationDidBecomeActiveNotification object:nil] subscribeNext:^(NSNotification * _Nullable x) {
NSLog(@"%@",x);
}];
3.KVO转Block
[RACObserve(self.person, name) subscribeNext:^(id _Nullable x) {
self.label.text = x;
}];
三、注意事项：
RAC使用@weakify(self);和@strongify(self);来避免block循环引用
@weakify(self);
[[self.textField rac_textSignal] subscribeNext:^(NSString * _Nullable x) {
@strongify(self);
self.textField.text = @"Hello";
}];
