ios 使用MKMapView时如何设置精度和距离过滤器

How to set accuracy and distance filter when using MKMapView

提问by Van Du Tran

When i use setShowsUserLocationwith MKMapViewto track user location, how do I set the accuracy and distance filter? I am not talking about CLLocationManager.

当我使用setShowsUserLocationwithMKMapView跟踪用户位置时，如何设置精度和距离过滤器？我不是在谈论CLLocationManager。

Thanks,

谢谢，

回答by Jano

You can't control the accuracy of the internal MKMapViewlocation manager (the one used to track the user with the blue dot), but you can create your own and use it to recenter the map. Here is a recipe...

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定位地图。这是一个食谱...

To handle core location permissions

处理核心位置权限

In the Core Location Delegate:

在核心位置代理中：

- (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);
    }
}

Right before setting up the location manager:

在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");
}

To setup core location

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];
}

To recenter the map with our location manager

使用我们的位置管理器重新调整地图

- (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];
}

Put that on the delegate. MKMapView doesn't have a distance or accuracy filter, only the CLLocationManager does. What MKMapView has is a region span around a point, in the example above 0.15 degrees (0.15*111 Km).

把它放在代表身上。MKMapView 没有距离或精度过滤器，只有 CLLocationManager 有。MKMapView 具有的是围绕一个点的区域跨度，在上面的示例中为 0.15 度（0.15*111 公里）。

Things that I tried and didn't work

我尝试过但没有奏效的事情

The documentation doesn't tell where MKMapViewis getting its updates from. I tried

文档没有说明从哪里MKMapView获取更新。我试过

- (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]]);
}

and I'm getting different values on each. It looks as if MKMapViewuses its own CLLocationManager, which means you can't set its accuracy. You can't add your delegate for the CLLocationManagerof the MKMapVieweither.

我对每个都有不同的价值。它看起来好像MKMapView使用自己的CLLocationManager，这意味着您无法设置其准确性。你不能加入你委托的CLLocationManager的MKMapView任。

My impression is that the only way to set the accuracy is setting show user position to NO and create a custom annotation with a blue dot, which means recentering the map manually as posted. You can get the blue dot graphic from the SDK with the github project artwork-extractor.

我的印象是设置精度的唯一方法是将显示用户位置设置为 NO 并创建一个带有蓝点的自定义注释，这意味着在发布时手动重新定位地图。您可以使用 github 项目图稿提取器从 SDK 中获取蓝点图形。

I don't know if I'm missing something or this part of MKMapViewjust sucks.

我不知道是我遗漏了什么还是这部分MKMapView很烂。

回答by morroko

For displaying map here is an example code.

在这里显示地图是一个示例代码。

First import MKMapKit and CoreLocation framework in your .h file.

首先在 .h 文件中导入 MKMapKit 和 CoreLocation 框架。

#import <MapKit/MapKit.h>
 #import <CoreLocation/CoreLocation.h>

Add MKMapKit and CoreLocation Delegate in .h file

在 .h 文件中添加 MKMapKit 和 CoreLocation Delegate

@interface MapViewController : UIViewController <MKMapViewDelegate, CLLocationManagerDelegate>


CGPoint gameMapCenter = CGPointMake([[UIScreen mainScreen] bounds].size.width / 2, [[UIScreen mainScreen] bounds].size.height / 2);
    gameMapView = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, 640, 620)];
    [gameMapView setCenter:gameMapCenter];
    [gameMapView setMapType:MKMapTypeStandard];
    [gameMapView setDelegate:self];
    [self.view addSubview:gameMapView];
    [gameMapView setShowsUserLocation:YES];

Use CLLocationManagerfor fetching user location.

使用CLLocationManager用于获取用户的位置。

Declare an instance of CLLocationManager

声明一个 CLLocationManager 实例

CLLocationManager *locationManager;

In ViewDidLoad

在 ViewDidLoad

locationManager = [[CLLocationManager alloc] init];

[locationManager setDelegate:self];

[locationManager setDesiredAccuracy:kCLLocationAccuracyBest];

[locationManager setDistanceFilter:kCLDistanceFilterNone];

[locationManger startUpdatingLocation];

startUpdatingLocationMethod Implementation:

startUpdatingLocation方法实现：

(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation 
{
      //Your Stuff
}

回答by nonamelive

You can't set the accuracy, however, you can get the accuracy via the userLocation in the MKMapView delegate method.

您无法设置精度，但是，您可以通过 MKMapView 委托方法中的 userLocation 获取精度。

- (void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation
{
    NSLog(@"%f", userLocation.location.horizontalAccuracy);
}