ios链式开发 oc 移除项目中的delegate，让bloc

之前发现了一种类似block串行执行的开发方式，今天终于不忙了就简单写一下做个笔记

链式调用

其实很简单，需要注意的就是相应对象的返回值，如下拿 person 和boy两个对象举例，最后实现 person.person(NO).strongMan(@"强壮的小男孩").boy(@"小男孩儿开始说").speak(@"我想回家");

Person.h

#import <Foundation/Foundation.h>
@class Boy;
@interface Person : NSObject
@property (nonatomic,readonly) Person *(^person)(BOOL enable);
@property (nonatomic,readonly) Person *(^strongMan)(NSString *str);
@property (nonatomic,readonly) Boy *(^boy)(NSString *str);
@end

Person.m

#import "Person.h"
#import "Boy.h"
@implementation Person
-(Person *(^)(BOOL))person{
    return ^(BOOL enable){
        NSLog(@"Person Say:%d\n",enable);
        return self;
    };
}

-(Person *(^)(NSString *))strongMan{
    return ^(NSString *str){
        NSLog(@"%@\n",str);
        return self;
    };
}

-(Boy *(^)(NSString *))boy{
    return ^(NSString *str){
        NSLog(@"%@\n",str);
        return [[Boy alloc]init];
    };
}
@end

boy.h

#import <Foundation/Foundation.h>
@interface Boy : NSObject
@property (nonatomic,readonly)Boy *(^speak)(NSString *speakStr);
@end

boy.m

#import "Boy.h"
@implementation Boy
-(Boy *(^)(NSString *))speak{
    return ^(NSString *speakStr){
        NSLog(@"speak:%@\n",speakStr);
        return self;
    };
}
@end

vc调用--------------------------------------------------

- (void)viewDidLoad {
    [super viewDidLoad];
    person.person(NO).strongMan(@"强壮的小男孩").boy(@"小男孩儿开始说").speak(@"我想回家");
}

打印结果

一般的使用到此就结束了，下面来稍微加点难度，前面的我们都看到了，都是正向传值，都是调用方直接告诉被调用方要干什么什么，那么我们如果需要调用方回传一些数据做处理呢，大家自己思考一下再往下看

思路是这样的，既然要反向且又想链式，那么自然想到了block，我们在被调用方的参数中修改参数为block是否能实现呢，继续往下看

拿系统定位功能CLLocationManager来做例子，调用定位，我们首先要检查权限、设置参数、开始定位、然后定位代理成功回调处理、失败处理这几个功能，我们最终的实现结果需要是这样的

    self.locationManager.checkAuthorization(NO).startLocation().locationSuccess(^(NSDictionary *addressDict) {
        NSLog(@"定位成功");
    }).locationError(^(NSError *error){
        NSLog(@"定位失败");
    });

1.首先我们声明这几个block

###JoyLocationManager.h
@property (nonatomic,readonly)JoyLocationManager *(^checkAuthorization)(BOOL backGroundModel);
@property (nonatomic,readonly)JoyLocationManager *(^startLocation)();
@property (nonatomic,readonly)JoyLocationManager *(^stopLocation)();
//参数为idblock类型(我这是定义的id类型参数的回调)
@property (nonatomic,copy)JoyLocationManager    *(^locationSuccess)(IDBLOCK block);
//参数为idblock类型(我这是定义的error类型参数的回调)
@property (nonatomic,copy)JoyLocationManager    *(^locationError)(ERRORBLOCK block);

2.这几个block
###JoyLocationManager.m
#pragma mark 检查权限
-(JoyLocationManager *(^)(BOOL))checkAuthorization{
    return ^(BOOL backGroundModel){
        [self checkAuthorStateAndSetBackModel:backGroundModel];//检查权限并设置是否后台运行模式
        return self;
    };
}

#pragma mark 开始定位
-(JoyLocationManager *(^)())startLocation{
    return ^(){
        [self startManagerLocation];//开始定位
        return self;
    };
}

#pragma mark 结束定位
-(JoyLocationManager *(^)())stopLocation{
    return ^(){
        [self stopManagerLocation];  //结束定位
        return self;
    };
}

#pragma mark 定位成功
-(JoyLocationManager *(^)(IDBLOCK block))locationSuccess{
    return ^(IDBLOCK block){
//runtime关联对象，定位成功代理中回调参数
        objc_setAssociatedObject(self, _cmd, block, OBJC_ASSOCIATION_COPY);
        return self;
    };
}

#pragma mark 定位失败
-(JoyLocationManager *(^)(ERRORBLOCK))locationError{
    return ^(ERRORBLOCK block){
//runtime关联对象，定位失败代理中回调参数
        objc_setAssociatedObject(self, _cmd, block, OBJC_ASSOCIATION_COPY);
        return self;
    };
}

#pragma mark 定位代理   
//CLLocation这个类里面包括的一些常用的位置信息有经度、纬度、海拔、速度、精确度
-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations{
  //定位成功进行地理反编码，可以改进一下考虑自行加入到链中
    [self reverseGEOCodeLocation:locations.firstObject];
    [self stopManagerLocation];
}

//定位失败
-(void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error{
//拿到前面关联的block并回调参数
    ERRORBLOCK successBlock = objc_getAssociatedObject(self, @selector(locationError));
    successBlock?successBlock(error):nil;
}

//反地理编码
- (void)reverseGEOCodeLocation:(CLLocation *)location{
    CLGeocoder *revGeo = [[CLGeocoder alloc] init];
    [revGeo reverseGeocodeLocation:location
                 completionHandler:^(NSArray *placemarks, NSError *error) {
                     if (!error && [placemarks count] > 0)
                     {
                         NSDictionary *dict =
                         [[placemarks objectAtIndex:0] addressDictionary];
                         IDBLOCK successBlock = objc_getAssociatedObject(self, @selector(locationSuccess));
                         successBlock?successBlock(dict):nil;
                     }else{
                         NSLog(@"ERROR: %@", error);
                     }
                 }];
}

到此可以试试了

self.locationManager.checkAuthorization(NO).startLocation().locationSuccess(^(NSDictionary *addressDict) {
        NSLog(@"定位成功");
    }).locationError(^(NSError *error){
        NSLog(@"定位失败");
    });

成功回走成功的回调，失败会走失败的回调，大家可以自行去试试把定位精度、headupdate、地理编码等试试加进来