写在前面：
项目需求用到这个功能，主要目的是实现老师设置位置签到范围，学生在一定范围内进行签到的功能。功能如下方截图：

屏幕快照 2019-01-28 上午10.29.26.png

简要介绍：

下面记录一下主要的实现流程，功能的实现主要是根据百度地图开发者官网提供的api文档，各项功能之间组合。百度地图的SDK现在分成了地图功能和定位功能两块不同的SDK，BaiduMapAPI这个是基础的地图功能，BMKLocationKit这个是定位功能。项目里实现定位签到功能用的的SDK包括上面说的这两个模块，所以在用cocopods引入framework的时候，需要引入：#百度地图 pod 'BMKLocationKit' pod 'BaiduMapKit'

功能实现

一、在APPdelegate.m文件中引入：

#import <BaiduMapAPI_Base/BMKBaseComponent.h>
#import <BMKLocationKit/BMKLocationComponent.h>

加入功能代码：

#pragma mark 百度地图设置
- (void)configBaiduMap {
    NSString *ak = @"xxxx";
    BMKMapManager *mapManager = [[BMKMapManager alloc] init];
    self.mapManager = mapManager;
    BOOL ret = [mapManager start:ak generalDelegate:nil];
    [[BMKLocationAuth sharedInstance] checkPermisionWithKey:ak authDelegate:self];
    if (!ret) {
        NSLog(@"manager start failed!");
    } 
}

二、在用到地图定位功能的viewController中

#import <BMKLocationKit/BMKLocationComponent.h>
#import <BaiduMapAPI_Base/BMKBaseComponent.h>//引入base相关所有的头文件
#import <BaiduMapAPI_Map/BMKMapComponent.h>//引入地图功能所有的头文件

遵循协议<BMKMapViewDelegate,BMKLocationManagerDelegate>

声明全局变量
@property (nonatomic, strong) BMKUserLocation *userLocation; //当前位置对象
@property (nonatomic, strong) BMKLocationManager *locationManager;/** locationManager*/
@property (nonatomic, strong) BMKMapView *mapView;/** 百度地图*/
//@property (nonatomic, strong) BMKPointAnnotation* annotation ;/** 标记*/
@property (nonatomic, strong) NSMutableArray *annotationArr;/** 标记数组*/
@property (nonatomic, strong) NSMutableArray *circleArr;/** 圆形数组*/

地图SDK文档中建议在以下代码中如此设置， 目的是控制内存

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    [_mapView viewWillAppear];
    _mapView.delegate = self;
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    [_mapView viewWillDisappear];
    _mapView.delegate = nil;
}

- (void)dealloc {
    if (_mapView) {
        _mapView = nil;
    }
}

初始化数组，这两个数组在接下来会用到

- (NSMutableArray *)annotationArr {
 
    if (!_annotationArr) {
        _annotationArr = [NSMutableArray array];
    }
    return _annotationArr;
}

- (NSMutableArray *)circleArr {
    if (!_circleArr) {
        _circleArr = [NSMutableArray array];
    }
    return _circleArr;
}

添加地图view

#pragma mark 添加地图
- (void)addSignMapBgView {
    if (!self.mapBgView) {
        UIView *mapBgView = [UIView new];
        self.mapBgView = mapBgView;
        mapBgView.backgroundColor = [CommUtls colorWithHexString:APP_BgColor];
        [self addSubview:mapBgView];
        [mapBgView makeConstraints:^(MASConstraintMaker *make) {
            make.top.equalTo(self.tipView.bottom);
            make.left.right.bottom.equalTo(0);
        }];
        
        _mapView = [[BMKMapView alloc] initWithFrame:CGRectZero];
//        _mapView.delegate = self;
        [_mapView setZoomLevel:21];//精确到5米
        _mapView.showsUserLocation = YES;//显示定位图层
        [mapBgView addSubview:_mapView];
        [_mapView makeConstraints:^(MASConstraintMaker *make) {
            make.edges.equalTo(0);
        }];
        _mapView.userTrackingMode = BMKUserTrackingModeNone;
        
    }

}

初始化地图定位：这里我用的是一次定位而没有选择持续定位。

#pragma mark 初始化locationManager
- (void)initUserLocationManager {
    //因为mapView是在一个分离出来的view中创建的，所以在这里将signSetTypeView中的mapView赋给当前viewcontroller的mapView；
    self.mapView = self.mainView.signSetTypeView.mapView;
    self.mapView.delegate = self;
//    self.annotation = [[BMKPointAnnotation alloc] init];
    
    // self.mapView是BMKMapView对象
    //精度圈设置
    BMKLocationViewDisplayParam *param = [[BMKLocationViewDisplayParam alloc] init];
    //设置显示精度圈，默认YES
    param.isAccuracyCircleShow = YES;
    //精度圈 边框颜色
    param.accuracyCircleStrokeColor = [UIColor colorWithRed:242/255.0 green:129/255.0 blue:126/255.0 alpha:1];
    //精度圈 填充颜色
    param.accuracyCircleFillColor = [UIColor colorWithRed:242/255.0 green:129/255.0 blue:126/255.0 alpha:0.3];
    [self.mapView updateLocationViewWithParam:param];
    
    self.userLocation = [[BMKUserLocation alloc] init];
    //初始化实例
    _locationManager = [[BMKLocationManager alloc] init];
    //设置delegate
    _locationManager.delegate = self;
    //设置返回位置的坐标系类型
    _locationManager.coordinateType = BMKLocationCoordinateTypeBMK09LL;
    //设置距离过滤参数
    _locationManager.distanceFilter = kCLDistanceFilterNone;
    //设置预期精度参数
    _locationManager.desiredAccuracy = kCLLocationAccuracyBest;
    //设置应用位置类型
    _locationManager.activityType = CLActivityTypeAutomotiveNavigation;
    //设置是否自动停止位置更新
    _locationManager.pausesLocationUpdatesAutomatically = NO;
    //设置是否允许后台定位
    //_locationManager.allowsBackgroundLocationUpdates = YES;
    //设置位置获取超时时间
    _locationManager.locationTimeout = 15;
    //设置获取地址信息超时时间
    _locationManager.reGeocodeTimeout = 15;
    //请求一次定位
    [self requestLocation];
}

请求定位，获取经纬度

#pragma mark 请求定位
- (void)requestLocation {
    
    [_locationManager requestLocationWithReGeocode:YES withNetworkState:YES completionBlock:^(BMKLocation * _Nullable location, BMKLocationNetworkState state, NSError * _Nullable error) {
        if (error)
        {
            NSLog(@"locError:{%ld - %@};", (long)error.code, error.localizedDescription);
        }
        if (location) {//得到定位信息，添加annotation
            
            if (location.location) {
                NSLog(@"LOC = %@",location.location);
            }
            if (location.rgcData) {
                NSLog(@"rgc = %@",[location.rgcData description]);
            }
            
            if (!location) {
                return;
            }
            if (!self.userLocation) {
                self.userLocation = [[BMKUserLocation alloc] init];
            }
            self.userLocation.location = location.location;
            [self.mapView updateLocationData:self.userLocation];
            CLLocationCoordinate2D mycoordinate = location.location.coordinate;
            self.mapView.centerCoordinate = mycoordinate;
            
            //赋予初始值
            self.viewModel.lat = [NSString stringWithFormat:@"%f", location.location.coordinate.latitude];
            self.viewModel.lng = [NSString stringWithFormat:@"%f",location.location.coordinate.longitude];
            self.viewModel.radius = @"50";
            
            //打印经纬度
            NSLog(@"didUpdateUserLocation lat %f,long %f",location.location.coordinate.latitude,location.location.coordinate.longitude);
        }
        NSLog(@"netstate = %d",state);
    }];
}

地图长按选点功能实现：

//长按地图选点
- (void)mapview:(BMKMapView *)mapView onLongClick:(CLLocationCoordinate2D)coordinate {
    
    if (self.annotationArr.count > 0) {
        [mapView removeAnnotations:self.annotationArr];
        [self.annotationArr removeAllObjects];
        
        BMKPointAnnotation *annotation = [[BMKPointAnnotation alloc]init];
        annotation.coordinate = coordinate;
        [self.annotationArr addObject:annotation];
        [mapView addAnnotations:self.annotationArr];
    } else {
        BMKPointAnnotation *annotation = [[BMKPointAnnotation alloc]init];
        annotation.coordinate = coordinate;
        [self.annotationArr addObject:annotation];
        [mapView addAnnotations:self.annotationArr];
    }
    //弹出半径选择框
    [self showLocationSelectRadiusViewWithCoordinate:coordinate];
}

选点后弹出选择定位范围弹框

#pragma mark 弹出位置弹框
- (void)showLocationSelectRadiusViewWithCoordinate:(CLLocationCoordinate2D)coordinate {
    ExtraActLocationSignPopView *popView = [ExtraActLocationSignPopView new];
    [popView show];
    @weakify(self);
    [popView.locatioonSureSignal subscribeNext:^(NSString *x) {
        @strongify(self);
        self.viewModel.radius = x;
        CGFloat radius = [x floatValue];
        [self circleWithCenterWithCoordinate2D:coordinate radius:radius];
    }];
}

设置好定位点以及半径范围后绘制范围圈，开始的时候声明的circleArr在这里用来盛放添加的区域圆形，在添加新的圆圈的时候，将之前旧的移除，保证每次绘制的范围都是最新的，同理annotationArr也是这个功能，因为API有提供的- (void)addOverlays:(NSArray *)overlays;这个方法：/** *向地图窗口添加一组Overlay，需要实现BMKMapViewDelegate的-mapView:viewForOverlay:函数来生成标注对应的View *@param overlays 要添加的overlay数组 */

#pragma mark 添加区域圆形覆盖
- (void)circleWithCenterWithCoordinate2D:(CLLocationCoordinate2D )coor radius:(CGFloat)radius {
    
    NSLog(@"coordinate lat %f,long %f",coor.latitude,coor.longitude);
    //赋予点击选点值
    self.viewModel.lat = [NSString stringWithFormat:@"%f", coor.latitude];
    self.viewModel.lng = [NSString stringWithFormat:@"%f",coor.longitude];
    
    if (self.circleArr.count > 0) {
        [_mapView removeOverlays:self.circleArr];
        [self.circleArr removeAllObjects];
        
        BMKCircle *circle = [BMKCircle circleWithCenterCoordinate:coor radius:radius];
        [self.circleArr addObject:circle];
        [_mapView addOverlays:self.circleArr];
    } else {
        BMKCircle *circle = [BMKCircle circleWithCenterCoordinate:coor radius:radius];
        [self.circleArr addObject:circle];
        [_mapView addOverlays:self.circleArr];
    }
}

#pragma mark 重绘overlay
- (BMKOverlayView *)mapView:(BMKMapView *)mapView viewForOverlay:(id <BMKOverlay>)overlay{
    if ([overlay isKindOfClass:[BMKCircle class]]){
        BMKCircleView* circleView = [[BMKCircleView alloc] initWithOverlay:overlay];
        circleView.fillColor = [UIColor colorWithRed:33/255.0 green:196/255.0 blue:206/255.0 alpha:0.3];
        circleView.strokeColor = [UIColor colorWithRed:33/255.0 green:196/255.0 blue:206/255.0 alpha:1];
        circleView.lineWidth = 1.0;
        return circleView;
    }
    return nil;
}

至此，在地图上选点进行签到功能基本实现，另外，关于 自定义的范围圆圈的颜色，边框大小都是可以自定义的，选点的标记也是可以自定义的，官方文档有说明