代码地址如下:
http://www.demodashi.com/demo/11107.html高仿系统指南针,方向数据是地磁航向数据,有定位地理位置信息和地磁方向信息,可以和系统的指南针对比看一看。
一、运行效果预览
二、实现过程
1.继承于UIView创建一个带刻度标注的视图ScaleView,利用UIBezierPath和CAShapeLayer、UILabel,默认0刻度(北)在最上方。
//化刻度表
- (void)paintingScale{CGFloat perAngle = M_PI/(90);NSArray *array = @[@"北",@"东",@"南",@"西"];//画圆环,每隔2°画一个弧线,总共180条for (int i = 0; i < 180; i++) {CGFloat startAngle = (-(M_PI_2+M_PI/180/2)+perAngle*i);CGFloat endAngle = startAngle+perAngle/2;UIBezierPath *bezPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.frame.size.width/2, self.frame.size.height/2)radius:(self.frame.size.width/2 - 50)startAngle:startAngleendAngle:endAngleclockwise:YES];CAShapeLayer *shapeLayer = [CAShapeLayer layer];//每隔30°画一个白条刻度if (i%15 == 0) {shapeLayer.strokeColor = [[UIColor whiteColor] CGColor];shapeLayer.lineWidth = 20;}else{shapeLayer.strokeColor = [[UIColor grayColor] CGColor];shapeLayer.lineWidth = 10;}shapeLayer.path = bezPath.CGPath;shapeLayer.fillColor = [UIColor clearColor].CGColor;[_backgroundView.layer addSublayer:shapeLayer];//每隔30°画一个刻度的标注 0 30 60...if (i % 15 == 0){NSString *tickText = [NSString stringWithFormat:@"%d",i * 2];CGFloat textAngel = startAngle+(endAngle-startAngle)/2;CGPoint point = [self calculateTextPositonWithArcCenter:CGPointMake(self.frame.size.width/2, self.frame.size.height/2)Angle:textAngel andScale:1.2];UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(point.x, point.y, 30, 15)];label.center = point;label.text = tickText;label.textColor = [UIColor whiteColor];label.font = [UIFont systemFontOfSize:15];label.textAlignment = NSTextAlignmentCenter;[_backgroundView addSubview:label];//标注 北 东 南 西if (i%45 == 0){tickText = array[i/45];CGPoint point2 = [self calculateTextPositonWithArcCenter:CGPointMake(self.frame.size.width/2, self.frame.size.height/2)Angle:textAngel andScale:0.8];UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(point2.x, point2.y, 30, 20)];label.center = point2;label.text = tickText;label.textColor = [UIColor whiteColor];label.font = [UIFont systemFontOfSize:20];label.textAlignment = NSTextAlignmentCenter;if ([tickText isEqualToString:@"北"]) {UILabel * markLabel = [[UILabel alloc]initWithFrame:CGRectMake(point.x, point.y, 8, 8)];markLabel.center = CGPointMake(point.x, point.y + 12);markLabel.clipsToBounds = YES;markLabel.layer.cornerRadius = 4;markLabel.backgroundColor = [UIColor redColor];[_backgroundView addSubview:markLabel]; }[_backgroundView addSubview:label];}}} //画十字线,参照线UIView * levelView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width/2/2, 1)];levelView.center = CGPointMake(self.frame.size.width/2, self.frame.size.height/2);levelView.backgroundColor = [UIColor whiteColor];[self addSubview:levelView];UIView * verticalView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 1, self.frame.size.width/2/2)];verticalView.center = CGPointMake(self.frame.size.width/2, self.frame.size.height/2);verticalView.backgroundColor = [UIColor whiteColor];[self addSubview:verticalView];UIView * lineView = [[UIView alloc] initWithFrame:CGRectMake(self.frame.size.width/2 -1.5, self.frame.size.height/2 - (self.frame.size.width/2 - 50) - 50, 3, 30 + 30)];lineView.backgroundColor = [UIColor whiteColor];[self addSubview:lineView];
}
2、利用CLLocationManager初始化定位装置,并设置代理 ,记得在info.plist中加入隐私定位权限关键字 Privacy - Location When In Use Usage Description
// 注意开启手机的定位服务,隐私那里的self.locationManager = [[CLLocationManager alloc]init];self.locationManager.delegate=self;// 定位频率,每隔多少米定位一次// 距离过滤器,移动了几米之后,才会触发定位的代理函数self.locationManager.distanceFilter = 0;// 定位的精度,越精确,耗电量越高self.locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;//导航//请求允许在前台获取用户位置的授权[self.locationManager requestWhenInUseAuthorization];//允许后台定位更新,进入后台后有蓝条闪动self.locationManager.allowsBackgroundLocationUpdates = YES;//判断定位设备是否能用和能否获得导航数据if ([CLLocationManager locationServicesEnabled]&&[CLLocationManager headingAvailable]){[self.locationManager startUpdatingLocation];//开启定位服务[self.locationManager startUpdatingHeading];//开始获得航向数据}else{NSLog(@"不能获得航向数据");}
通过实现定位装置的代理方法:
-(void)locationManager:(CLLocationManager )manager didUpdateHeading:(CLHeading )newHeading 来获得地理和地磁航向数据,从而转动地理刻度表以及表上的文字标注;
方法-(BOOL)locationManagerShouldDisplayHeadingCalibration:(CLLocationManager *)manager返回Yes是为了受到外来磁场干扰时,设备会自动进行校验。
#pragma mark - CLLocationManagerDelegate
//获得地理和地磁航向数据,从而转动地理刻度表
-(void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading{//获得当前设备UIDevice *device =[UIDevice currentDevice];// 判断磁力计是否有效,负数时为无效,越小越精确if (newHeading.headingAccuracy>0){//地磁航向数据-》magneticHeadingfloat magneticHeading =[self heading:newHeading.magneticHeading fromOrirntation:device.orientation];//地理航向数据-》trueHeadingfloat trueHeading =[self heading:newHeading.trueHeading fromOrirntation:device.orientation];//地磁北方向float heading = -1.0f *M_PI *newHeading.magneticHeading /180.0f;_angleLabel.text = [NSString stringWithFormat:@"%3.1f°",magneticHeading];//旋转变换[_scaView resetDirection:heading]; //返回当前手机(摄像头)朝向方向[self updateHeading:newHeading]; }
}
//判断设备是否需要校验,受到外来磁场干扰时
-(BOOL)locationManagerShouldDisplayHeadingCalibration:(CLLocationManager *)manager
{return YES;
}
//旋转重置刻度标志的方向
- (void)resetDirection:(CGFloat)heading{_backgroundView.transform = CGAffineTransformMakeRotation(heading);for (UILabel * label in _backgroundView.subviews) {label.transform = CGAffineTransformMakeRotation(-heading);}
}
3、通过代理方法获得经纬度以及海拔数据,然后利用经纬度进行地理反编码获得地理位置信息。
// 定位成功之后的回调方法,只要位置改变,就会调用这个方法
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations{self.currLocation = [locations lastObject];//维纬度NSString * latitudeStr = [NSString stringWithFormat:@"%3.2f",_currLocation.coordinate.latitude];//经度NSString * longitudeStr = [NSString stringWithFormat:@"%3.2f",_currLocation.coordinate.longitude];//高度NSString * altitudeStr = [NSString stringWithFormat:@"%3.2f",_currLocation.altitude];NSLog(@"纬度 %@ 经度 %@ 高度 %@", latitudeStr, longitudeStr, altitudeStr);_latitudlongitudeLabel.text = [NSString stringWithFormat:@"纬度:%@ 经度:%@ 海拔:%@", latitudeStr, longitudeStr, altitudeStr];CLGeocoder *geocoder = [[CLGeocoder alloc] init];[geocoder reverseGeocodeLocation:self.currLocationcompletionHandler:^(NSArray *placemarks, NSError *error) {if ([placemarks count] > 0) {CLPlacemark *placemark = placemarks[0];NSDictionary *addressDictionary = placemark.addressDictionary;NSString *street = [addressDictionaryobjectForKey:(NSString *)kABPersonAddressStreetKey];street = street == nil ? @"": street;NSString *country = placemark.country;NSString * subLocality = placemark.subLocality;NSString *city = [addressDictionaryobjectForKey:(NSString *)kABPersonAddressCityKey];city = city == nil ? @"": city;NSLog(@"%@",[NSString stringWithFormat:@"%@ \n%@ \n%@ %@ ",country, city,subLocality ,street]);_positionLabel.text = [NSString stringWithFormat:@" %@\n %@ %@%@ " ,country, city,subLocality ,street];}}];
}
三、项目结构截图
iOS 指南针
代码地址如下:
http://www.demodashi.com/demo/11107.html注:本文著作权归作者,由demo大师发表,拒绝转载,转载需要作者授权