iphone – 如何设置精度和距离过滤器使用MKMapView时

您无法控制内部MKMapView位置管理器(用于使用蓝点跟踪用户的位置管理器)的准确性，但您可以创建自己的位置管理器，并使用它来重新生成地图。这是一个食谱…

处理核心位置权限

在核心位置代表：

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
    if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied){
        NSLog(@"User has denied location services");
    } else {
        NSLog(@"Location manager did fail with error: %@",error.localizedFailureReason);
    }
}

设置位置管理器之前：

if (![CLLocationManager locationServicesEnabled]){
    NSLog(@"location services are disabled"];
    return;
}
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied){
    NSLog(@"location services are blocked by the user");
    return;
}
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusAuthorized){
    NSLog(@"location services are enabled");
}  
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusNotDetermined){
    NSLog(@"about to show a dialog requesting permission");
}

设置核心位置

self.locationManager = [CLLocationManager new];
self.locationManager.purpose = @"Tracking your movements on the map.";
self.locationManager.delegate = self;

/* Pinpoint our location with the following accuracy:
 *
 *     kCLLocationAccuracyBestForNavigation  highest + sensor data
 *     kCLLocationAccuracyBest               highest     
 *     kCLLocationAccuracyNearestTenMeters   10 meters   
 *     kCLLocationAccuracyHundredMeters      100 meters
 *     kCLLocationAccuracyKilometer          1000 meters 
 *     kCLLocationAccuracyThreeKilometers    3000 meters
 */
self.locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters;

/* Notify changes when device has moved x meters.
 * Default value is kCLDistanceFilterNone: all movements are reported.
 */
self.locationManager.distanceFilter = 10.0f;

/* Notify heading changes when heading is > 5.
 * Default value is kCLheadingFilterNone: all movements are reported.
 */
self.locationManager.headingFilter = 5;

// update location
if ([CLLocationManager locationServicesEnabled]){
    [self.locationManager startUpdatingLocation];
}

使用我们的位置管理器重新显示地图

- (void)locationManager:(CLLocationManager *)manager 
    didUpdateToLocation:(CLLocation *)newLocation 
           fromLocation:(CLLocation *)oldLocation 
{
    MKCoordinateRegion region = { { 0.0f,0.0f },{ 0.0f,0.0f } };
    region.center = newLocation.coordinate;
    region.span.longitudeDelta = 0.15f; 
    region.span.latitudeDelta = 0.15f;
    [self.mapView setRegion:region animated:YES];
}

把它放在代理上。 MKMapView没有距离或精度过滤器，只有CLLocationManager。 MKMapView有一个区域跨越一个点，在上面的例子中，0.15度(0.15 * 111公里)。

事情，我试过，没有工作

该文档不知道哪里的MKMapView获取其更新。我试过了

- (void)locationManager:(CLLocationManager *)manager 
    didUpdateToLocation:(CLLocation *)newLocation 
           fromLocation:(CLLocation *)oldLocation {
    NSLog(@"newLocation %@",newLocation.timestamp);
    NSLog(@"last map location %@",[NSString stringWithFormat:@"%@",[[[self.mapView userLocation] location] timestamp]]);
}

我每个都得到不同的值。看起来像MKMapView使用它自己的CLLocationManager，这意味着你不能设置其准确性。您不能为MKMapView的CLLocationManager添加您的委托。

我的印象是，唯一的设置准确性的方法是将用户位置设置为NO，并创建一个带有蓝点的自定义注释，这意味着手动重新绘制地图。您可以使用github项目图稿提取器从SDK获取蓝点图形。

我不知道我是否缺少某些东西，或者这部分MKMapView只是吮吸了。