Question

我正在开发一个应用程序，旨在在地图上显示iPhone在活动期间的位置（在它们之间添加注释和绘制线）。

为此，我使用位置管理器获取新位置并通知MapDisplayViewController。当我在模拟器上使用时，我得到了很好的结果，你可以在这里看到http://www.youtube.com/watch?v=ESLIYSU_Mqw，但是对于iPhone，我得到了奇怪的结果，如200米错误。

我还使用MKMapView来显示设备位置。使用这些设置（下一个代码块）我得到了http://grab.by/mgUU。

如果我显示用户位置不同的结果，这是正常的吗？

- (void)setupMap {
self.mapView.delegate = self;

[self.mapView setUserTrackingMode:MKUserTrackingModeFollow animated:YES];
[self.mapView setUserInteractionEnabled:NO];

[self.mapView setShowsUserLocation:NO];
[self.mapView setZoomEnabled:NO];
[self.waitingView start];

}

这里有真实设备的截图：

背景：http://grab.by/mgN2
没有背景：http://grab.by/mgNc

编辑：差异来自我用于这两种情况，使用了两种获取设备当前位置的方法：

应用处于活动状态时来自mapView的句柄
当应用处于后台时来自位置管理器的句柄

混合两个地点系统是否合适？

我也测试了这个解决方案CLLocationManager and accuracy issues - any experiences?，但我得到了相同的结果。

谢谢;）

位置管理器的设置：

- (void)setup {
self.locationManager = [CLLocationManager new];
self.locationManager.delegate = self;

self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
self.isUpdatingLocation = NO;
}

在后台添加位置时

通知：

- (void)doUpdateWithLocation:(CLLocation *)location {

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

    [self beginBackgroundUpdateTask];


    NSLog(@"%s do update in background %@", __PRETTY_FUNCTION__, location);

    if (self.userLocationFound == NO && self.isUpdatingLocation == YES) {
        self.startCoordinate = CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude);

        self.userLocationFound = YES;
    }
    else if (self.isUpdatingLocation) {
        static int distance;

        ABGPSPosition *position = [[ABGPSPosition alloc] init];
        position.startPoint = MKMapPointForCoordinate(self.startCoordinate);
        position.endPoint = MKMapPointForCoordinate(location.coordinate);

        //INFO: Get the distance between this new point and the previous point.
        CLLocationDistance metersApart = MKMetersBetweenMapPoints(position.startPoint, position.endPoint);
        if (metersApart > MINIMUM_DELTA_METERS) {
            MKMapPoint points[2] = {position.startPoint, position.endPoint};


            distance += metersApart;
            NSLog(@"%s - %d", __PRETTY_FUNCTION__, distance);

            NSInteger count = [self.measurementArray count];
            [self willChange:NSKeyValueChangeInsertion
             valuesAtIndexes:[NSIndexSet indexSetWithIndex:count] forKey: @"measurementArray"];
            [self.measurementArray insertObject:location atIndex:count];
            [self didChange:NSKeyValueChangeInsertion
            valuesAtIndexes:[NSIndexSet indexSetWithIndex:count] forKey: @"measurementArray"];


            self.startCoordinate = CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude);
        }

    }

        [self endBackgroundUpdateTask];
    });
}

MapDisplayViewController获取新位置：

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{

if ([keyPath isEqualToString:keyPathMeasurementArray]) {
    if ([change[NSKeyValueChangeKindKey] intValue] == NSKeyValueChangeInsertion) {      

        NSIndexSet *insertedIndexSet = change[NSKeyValueChangeIndexesKey];

        [insertedIndexSet enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL *stop) {

            CLLocation *location = self.locationManager.measurementArray[idx];

            MKUserLocation *userLocation = [[MKUserLocation alloc] init];
            [userLocation setCoordinate:location.coordinate];
            NSLog(@"%s - didUpdateUserLocation", __PRETTY_FUNCTION__);

                [self.locationBackgroundList addObject:userLocation];
                NSLog(@"%s | %@", __PRETTY_FUNCTION__, self.locationBackgroundList);                
        }];
    }
}
else {
    [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
}
}

MapDisplayViewController添加注释新地图视图：

- (void)handleAddLocations {
NSLog(@"%s | %@", __PRETTY_FUNCTION__, self.locationBackgroundList);

if ([self.locationBackgroundList count] > 0) {
    for (MKUserLocation *backgroundUserLocation in self.locationBackgroundList) {

        {
            LocAnnotation* annotation = [[LocAnnotation alloc] initWithCoordinate:backgroundUserLocation.coordinate];
            NSLog(@"%s %@", __PRETTY_FUNCTION__, [backgroundUserLocation description]);



            [self.mapView addAnnotation:annotation];
        }
        [self mapView:self.mapView didUpdateUserLocation:backgroundUserLocation];
    }

    NSString *message = [NSString stringWithFormat:@"%s | Annotation number: %d", __PRETTY_FUNCTION__, [self.locationBackgroundList count]];
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Debug" message:message delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"OK", nil];
    [alert show];

    [self.locationBackgroundList removeAllObjects];
    self.locationBackgroundList = [[NSMutableArray alloc] init];
    }
}

Answer 1

修复了您必须使用一种方法来使用 CLLocationManager 或 MapView 来定位您的设备。 ;）

[iOS] [背景] [CLLocationManager]错误的地图准确性

1 个答案: