如何在MapView上绘制MKPolyline？ [英] How to draw a MKPolyline on a MapView?

问题描述

我有一个要在地图上绘制的点数组，它已经被解码了：

I have an array of points to be drawn on a map, its already decoded:

- (void) drawRoute:(NSArray *) path {
    NSInteger numberOfSteps = path.count;

    CLLocationCoordinate2D coordinates[numberOfSteps];
    for (NSInteger index = 0; index < numberOfSteps; index++) {
         CLLocation *location = [path objectAtIndex:index];
         CLLocationCoordinate2D coordinate = location.coordinate;

         coordinates[index] = coordinate;
    }

    MKPolyline *polyLine = [MKPolyline polylineWithCoordinates:coordinates count:numberOfSteps];
    [map addOverlay:polyLine];
}

其中map是MKMapView的一个实例，而数组的路径代表已解码的点集。

where "map" is an instance of MKMapView, and path the array representing the already decoded set of points.

我认为用 [map addOverlay：polyLine]; 这一行就可以了。我在某些页面中看到过这种方法：

I thought that with the line [map addOverlay:polyLine]; it would be drawn. I've seen in some pages this method:

- (MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id <MKOverlay>)overlay {
    MKPolylineView *polylineView = [[MKPolylineView alloc] initWithPolyline:overlay];
    polylineView.strokeColor = [UIColor redColor];
    polylineView.lineWidth = 1.0;

    return polylineView;
}

polylineView是否在地图上实际绘制了什么？我也尝试将MKPolyline（从上面的方法）传递给最后一个方法的< MKOverlay> overlay参数，但抛出异常。

Is the polylineView what is actually drawn on map? I've tried also to pass the MKPolyline (from the method above) to the "<MKOverlay> overlay" argument of this last method, but throws an exception.

我想我很接近，但我现在不知道该怎么办。

I think I'm close, but I don't know what to do now.

请帮忙！非常感谢你提前。

Please help! Thank you very much in advance.

推荐答案

完成。

这是一个非常愚蠢的事情，我没有为MapView设置委托。只需添加[map setDelegate：self];诀窍。

Was a very stupid thing, i didn't set the delegate for the MapView. Simply adding [map setDelegate:self]; did the trick.

无论如何，谢谢！。

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