Question

在我的一个应用中，我需要在2个RMPointAnnotation之间画一条线。我所做的就是在viewDidAppear中创建所有内容：

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];

    RMPointAnnotation *annotation = [[RMPointAnnotation alloc] initWithMapView:self.mapView
                                                                    coordinate:self.mapView.centerCoordinate
                                                                      andTitle:@"annotation"];
    [self.mapView addAnnotation:annotation];

    RMPointAnnotation *annotation2 = [[RMPointAnnotation alloc] initWithMapView:self.mapView
                                                                     coordinate:CLLocationCoordinate2DMake(self.mapView.centerCoordinate.latitude - 0.005, self.mapView.centerCoordinate.longitude + 0.005)
                                                                       andTitle:@"annotation 2"];
    [self.mapView addAnnotation:annotation2];

    RMAnnotation *lineAnnotation = [[RMAnnotation alloc] initWithMapView:self.mapView coordinate:annotation.coordinate andTitle:nil];
    [self.mapView addAnnotation:lineAnnotation];
}

然后我实现了mapView：layerForAnnotation：

- (RMMapLayer *)mapView:(RMMapView *)mapView layerForAnnotation:(RMAnnotation *)annotation
{
    if (annotation.isUserLocationAnnotation)
        return nil;

    RMShape *shape = [[RMShape alloc] initWithView:mapView];

    shape.lineColor = [UIColor orangeColor];
    shape.lineWidth = 5.0;

    for (RMAnnotation *annotation in (NSArray *)mapView.annotations) {
        if ([annotation isKindOfClass:[RMPointAnnotation class]]) {
            [self.shape addLineToCoordinate:annotation.coordinate];
        }
    }

    return self.shape;
}

但是因为我的RMPointAnnotation都是可拖动的，所以我想在拖动时不断重绘2个注释之间的界限。

如何使用MapBox实现这样的功能？

由于

Answer 1

因此，解决此问题的一种方法是创建自己的自定义视图，以跟上您的上一个位置。

@implementation CMLPointView

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        self.userInteractionEnabled = YES;
        self.layer.cornerRadius = frame.size.width/2;
    }
    return self;
}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    self.lastLocation = self.center;
}

您可以为坐标所需的每个点创建一个视图。我在视图控制器中运行此循环，以便我可以从那里处理平移手势。

for (CLLocation *loc in self.poiCoordinates) {
            CMLPointView *point = [[CMLPointView alloc] initWithFrame:CGRectMake([self.mapView coordinateToPixel:loc.coordinate].x-10.0f, [self.mapView coordinateToPixel:loc.coordinate].y-10.0f, 20.0f, 20.0f)];
            point.backgroundColor = [UIColor purpleColor];
            UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
            [point addGestureRecognizer:panRecognizer];

            [self.view addSubview:point];
}

为了实际处理平移，我每次创建一个新的RMAnnotation并为该注释绘制RMS形状。

- (void)handlePan: (UIPanGestureRecognizer *) pan
{
    CMLPointView *pointView = (CMLPointView *)pan.view;
    CGPoint translation = [pan translationInView:self.view];
    pointView.center = CGPointMake(pointView.lastLocation.x + translation.x,
                              pointView.lastLocation.y + translation.y);

    // Just trying to remove the annotation for RMShape
    [self.mapView removeAnnotation:[self.mapView.annotations lastObject]];

    RMAnnotation *annotation = [[RMAnnotation alloc] initWithMapView:self.mapView coordinate:[self.mapView pixelToCoordinate:pointView.center] andTitle:@"POI"];
    [self.poiCoordinates removeObjectAtIndex:0];
    [self.poiCoordinates insertObject:[[CLLocation alloc] initWithLatitude:[self.mapView pixelToCoordinate:pointView.center].latitude longitude:[self.mapView pixelToCoordinate:pointView.center].longitude] atIndex:0];
    annotation.userInfo = self.poiCoordinates;
    [annotation setBoundingBoxFromLocations:self.poiCoordinates];
    [self.mapView addAnnotation:annotation];
}

希望这有帮助！如果您对我做某事的原因有疑问，请发表评论。

拖动注释时如何重绘RMS形状？

1 个答案: