iOS定位和获取当前天气

　　这里是定义了一个类，用来当app 启动的时候，在后台获取当前和位置，并根据位置获取当前天气信息，当点击底部的 tabbar 显示我的控制器的时候，在页面上显示当前位置和当前的天气状况，天气接口用的 “心知天气” 这个免费的接口，因为是免费的所以天气信息很少，只能获取到当前温度、当前天气状况（晴还是雨）和指定的一组天气图片从他们网站下载下来直接拖进项目里面，根据天气状态显示指定的图片。(项目全面接入的MVVM 和 RAC)

　CHMLocationManager.h

#import "BaseViewModel.h"
#import "Config.h"

@class CHMSeniverseResultModel;

@interface CHMLocationManager : BaseViewModel

@property (nonatomic, assign) double latitude;
@property (nonatomic, assign) double longitude;
@property (nonatomic, assign) BOOL currentLocationAbility;
@property (nonatomic, strong) RACSubject *refreshSubject;
@property (nonatomic, strong) RACCommand *weatherDataCommand;
@property (nonatomic, copy) NSString *currentCity;
@property (nonatomic, strong) CHMSeniverseResultModel *seniverseResultModel;

+ (instancetype)sharedInstance;
- (void)startLocation;

@end

　CHMLocationManager.m

#import "CHMLocationManager.h"
#import <CoreLocation/CoreLocation.h>
#import "MBProgressHUD+Custom.h"
#import "MLNetworkingManager.h"
#import "NSString+Custom.h"
#import "CHMSeniverseResultModel.h"

#define kSeniverseAPI @"bfdvxqnyj8k2sooo"

@interface CHMLocationManager () <CLLocationManagerDelegate>

@property (nonatomic, strong) CLLocationManager *locationManager;
@property (nonatomic, strong) CLGeocoder *geocoder;

@end

@implementation CHMLocationManager

+ (instancetype)sharedInstance {
    static CHMLocationManager *locationManager = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        locationManager = [[CHMLocationManager alloc] init];
    });
    return locationManager;
}

- (void)xm_initialize {
    self.locationManager = [[CLLocationManager alloc] init];
    self.geocoder = [[CLGeocoder alloc] init];
    self.locationManager.delegate = self;
    self.locationManager.desiredAccuracy = kCLLocationAccuracyThreeKilometers;
    self.refreshSubject = [RACSubject subject];
}

- (void)startLocation {
    if ([self.locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) {
        if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.f) {
            [self.locationManager requestWhenInUseAuthorization];
        }
    }
    
    [self.locationManager startUpdatingLocation];
    
    if ([CLLocationManager locationServicesEnabled] && [CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied) {
        self.currentCity = NSLocalizedString(@"打开定位", nil);
        self.currentLocationAbility = NO;
    } else {
        self.currentLocationAbility = YES;
    }
}

#pragma mark - CLLocationManagerDelegate
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations {
    CLLocation *location = [locations lastObject];
    CLLocationCoordinate2D coordinate = location.coordinate;
    
    self.latitude = coordinate.latitude;
    self.longitude = coordinate.longitude;
    DebugLog(@"当前位置信息 %lf %lf", self.latitude, self.longitude);
    
    [manager stopUpdatingLocation];
    
    [self reverseCurrentGeocodeLocation:location];
}

- (void)reverseCurrentGeocodeLocation:(CLLocation *)location {
    @weakify(self);
    [self.geocoder reverseGeocodeLocation:location completionHandler:^(NSArray<CLPlacemark *> * _Nullable placemarks, NSError * _Nullable error) {
        @strongify(self);
        if (placemarks.count > 0) {
            CLPlacemark *place = [placemarks firstObject];
            if (place != nil) {
                if (place.locality && place.locality.length > 0) {
                    self.currentCity = place.locality;
                } else {
                    //四大直辖市的城市信息无法通过locality获得，只能通过获取省份的方法来获得（如果city为空，则可知为直辖市）
                    self.currentCity = place.administrativeArea;
                }

                [self.weatherDataCommand execute:@{@"location": [NSString stringWithFormat:@"%.2f:%.2f", self.latitude, self.longitude], @"language": [NSString currentLanguageForSeniverse]}];
            } else {
                DebugLog(@"CLPlacemark place 是 nil");
                self.currentCity = NSLocalizedString(@"位置未知", nil);
            }
        } else if (error == nil && placemarks.count == 0) {
            DebugLog(@"没有定位结果返回");
            self.currentCity = NSLocalizedString(@"没有定位信息", nil);
        } else {
            DebugLog(@"反地理编码失败 %@", error);
        }
        [self.refreshSubject sendNext:self.currentCity];
    }];
}

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
    [manager stopUpdatingLocation];
    
    switch (error.code) {
        case kCLErrorDenied:
        {
            DebugLog(@"用户拒绝了对位置或测距的访问权限");
            self.currentCity = NSLocalizedString(@"打开定位", nil);
        }
            break;
        default:
        {
            [MBProgressHUD showBriefPoint:NSLocalizedString(@"定位失败", nil)];
            self.currentCity = NSLocalizedString(@"定位失败", nil);
        }
            break;
    }
}

#pragma mark - Setter Getter
- (CHMSeniverseResultModel *)seniverseResultModel {
    if (!_seniverseResultModel) {
        _seniverseResultModel = [[CHMSeniverseResultModel alloc] init];
    }
    return _seniverseResultModel;
}

- (RACCommand *)weatherDataCommand {
    if (!_weatherDataCommand) {
        _weatherDataCommand = [[RACCommand alloc] initWithSignalBlock:^RACSignal *(NSDictionary *dic) {
            
            DebugLog(@"请求当前的天气情况 %@", dic);
            
            return [RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {
                
                MLURLSessionTask *task = [MLNetworkingManager requestWeatherWithAPI:kSeniverseAPI location:[dic objectForKey:@"location"] language:[dic objectForKey:@"language"] unit:@"c" success:^(CHMSeniverseResultModel *response) {
                    [CHMLocationManager sharedInstance].seniverseResultModel = response;
                    [subscriber sendNext:response];
                    [subscriber sendCompleted];
                } fail:^(NSError *error) {
                    [subscriber sendError:error];
                }];
                
                return [RACDisposable disposableWithBlock:^{
                    [task cancel];
                }];
            }];
        }];
    }
    return _weatherDataCommand;
}

@end

+ (MLURLSessionTask *)requestWeatherWithAPI:(NSString *)API location:(NSString *)location language:(NSString *)language unit:(NSString *)unit success:(MLResponseSuccess)success fail:(MLResponseFail)fail {
    NSString *tempURLStr = [NSString stringWithFormat:@"https://api.seniverse.com/v3/weather/now.json?key=%@&location=%@&language=%@&unit=%@", API, location, language, unit];
    
    NSURLSessionTask *task = [MLNetworking getWithUrl:tempURLStr refreshCache:YES showMBProHUD:NO success:^(id response) {
        CHMSeniverseResultModel *seniverseResultModel = [CHMSeniverseResultModel mj_objectWithKeyValues:((NSArray *)[response objectForKey:@"results"]).firstObject];
        seniverseResultModel.seniverseNowModel = [CHMSeniverseNowModel mj_objectWithKeyValues:[((NSArray *)[response objectForKey:@"results"]).firstObject objectForKey:@"now"]];
        seniverseResultModel.seniverseLocationModel = [CHMSeniverseLocationModel mj_objectWithKeyValues:[((NSArray *)[response objectForKey:@"results"]).firstObject objectForKey:@"location"]];
        
        if (success) {
            success(seniverseResultModel);
        }
        DebugLog(@"requestWeatherWithAPI %@", response);
    } fail:^(NSError *error) {
        if (fail) {
            fail(error);
        }
        [MLNetworkingManager showRequestFailInfo:kFailErrorUserInfoDataStr];
        DebugLog(@"requstWeatherWithAPI %@", error);
    }];
    
    return task;
}

END