文章系列
《ReactiveCocoa 概述》
《RACSignal》
《RACDisposable》
《RACSubject、RACReplaySubject(内附冷信号和热信号的区别)》
《集合RACTuple、RACSequence》
《RAC 中的通知、代理、KVO, 基本事件、方法的监听》
《rac_liftSelector》
《RACMulticastConnection》
《RACCommand》
《RAC - 核心方法bind》
《RAC - 定时器》
《RACScheduler》
《RAC - 点击获取验证码 demo》
《RAC - 映射(Map & flattenMap)》
《RAC信号操作解释合集》
《RAC - 信号的生命周期》
-
rac_addObserverForName(通知)
OC正常写法(需要自己单独实现noti: 方法去处理通知事件)
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(noti:) name:@"noti" object:nil];
OC 中使用RAC 写法
[[[NSNotificationCenter defaultCenter] rac_addObserverForName:@"noti" object:nil] subscribeNext:^(NSNotification * _Nullable x) {
// 处理通知事件
}];
↓rac_addObserverForName: 原理分析↓
- (RACSignal *)rac_addObserverForName:(NSString *)notificationName object:(id)object {
@unsafeify(object);
return [[RACSignal createSignal:^(id<RACSubscriber> subscriber) {
@strongify(object);
// 内部封装的 KVO
id observer = [self addObserverForName:notificationName object:object queue:nil usingBlock:^(NSNotification *note) {
// 发送监听信息
[subscriber sendNext:note];
}];
return [RACDisposable disposableWithBlock:^{
// 在取消订阅后, 移除观察者
[self removeObserver:observer];
}];
}] setNameWithFormat:@"-rac_addObserverForName: %@ object: <%@: %p>", notificationName, [object class], object];
}
-
代理
RACSubject 通常用来代替代理
rac_signalForSelector 也可以用做代理, 但是无法传值!
这里只说RACSubject , rac_signalForSelector 在下文中有详细介绍.
- 首先创建一个RedView的类继承于UIView
RedView.h
#import <UIKit/UIKit.h>
#import <ReactiveObjC/ReactiveObjC.h>
NS_ASSUME_NONNULL_BEGIN
@interface RedView : UIView
// rac 实现代理
@property (nonatomic, strong)RACSubject *subject;
@end
NS_ASSUME_NONNULL_END
RedView.m
#import "RedView.h"
@implementation RedView
- (RACSubject *)subject{
if(!_subject){
_subject = [RACSubject subject];
}
return _subject;
}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[self.subject sendNext:@"红色视图"];
}
@end
控制器中代码:
#import "ViewController.h"
#import <ReactiveObjC/ReactiveObjC.h>
#import "RedView.h"
@interface ViewController ()
@property (nonatomic, strong)RedView *red;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
[self delegateTest];
}
- (void)delegateTest {
self.red = [[RedView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
self.red.backgroundColor = [UIColor redColor];
[self.view addSubview:self.red];
[self.red.subject subscribeNext:^(id _Nullable x) {
NSLog(@"代理: %@", x);
}];
}
-
KVO
需要引入 #import <NSObject+RACKVOWrapper.h>头文件
方式一:
- (void)RAC_KVOTest1 {
self.kvoView = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
self.kvoView.backgroundColor = [UIColor redColor];
[self.view addSubview:self.kvoView];
[self.kvoView rac_observeKeyPath:@"frame" options:NSKeyValueObservingOptionNew observer:nil block:^(id value, NSDictionary *change, BOOL causedByDealloc, BOOL affectedOnlyLastComponent) {
NSLog(@"监听到最新frame - %@", value);
}];
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
self.kvoView.frame = CGRectMake(50, 50, 50, 50);
}
输出结果: 监听到最新frame - NSRect: {{50, 50}, {50, 50}}
方式二:
- (void)RAC_KVOTest2 {
self.kvoView = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
self.kvoView.backgroundColor = [UIColor redColor];
[self.view addSubview:self.kvoView];
[[self.kvoView rac_valuesForKeyPath:@"frame" observer:self] subscribeNext:^(id _Nullable x) {
// 刚开始运行, 就会先打印一遍原始值 -> 监听到最新frame - NSRect: {{100, 100}, {100, 100}}
NSLog(@"监听到最新frame - %@", x);
// 然后点击打印 -> 监听到最新frame - NSRect: {{50, 50}, {50, 50}}
}];
}
方式三:
- (void)RAC_KVOTest3 {
self.kvoView = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
self.kvoView.backgroundColor = [UIColor redColor];
[self.view addSubview:self.kvoView];
// 使用RAC 封装的宏定义, 打印结果和方式2 一样
[RACObserve(self.kvoView, frame) subscribeNext:^(id _Nullable x) {
NSLog(@"监听到最新frame - %@", x);
}];
}
注意: 方式2、3中有注释提到, 在监听过程中会出现先打印一次原始数据值
-
rac_signalForSelector(监听方法)
- (void)rac_signalForSelectorTest {
[[self rac_signalForSelector:@selector(touchesBegan:withEvent:)] subscribeNext:^(RACTuple * _Nullable x) {
NSLog(@"监听屏幕点击方法: %@", x);
}];
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
也可以用作代理的使用, 比如检测上面RedView 的点击事件
[[self.red rac_signalForSelector:@selector(touchesBegan:withEvent:)] subscribeNext:^(RACTuple * _Nullable x) {
NSLog(@"控制器知道RedView被点击了");
}];
-
rac_signalForControlEvents(监听事件)
- (void)rac_signalForControlEventsTest {
UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(200, 200, 100, 50)];
button.backgroundColor = [UIColor blueColor];
[self.view addSubview:button];
[[button rac_signalForControlEvents:UIControlEventTouchUpInside] subscribeNext:^(__kindof UIControl * _Nullable x) {
NSLog(@"按钮被点击了");
}];
}
-
rac_textSignal(监听textfield输入)
- (void)rac_textSignalTest {
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(200, 200, 100, 50)];
textField.layer.borderColor = [UIColor redColor].CGColor;
textField.layer.borderWidth = 1;
textField.layer.cornerRadius = 5;
textField.clipsToBounds = YES;
[self.view addSubview:textField];
[textField.rac_textSignal subscribeNext:^(NSString * _Nullable x) {
// x：是最新文本数据
NSLog(@"%@", x);
}];
}
-
RAC 的宏
RAC(<#TARGET, ...#>)
RAC(对象，对象的属性) = (一个信号);
比如：RAC(button, enable) = (RACSignal) 按钮的enable 等于一个信号
.End
