未绘制MapPolyline [英] MapPolyline not being drawn

问题描述

我正在尝试在地图中使用MapPolyLine来显示实时路线，希望它会移动/缩放.问题是该线未显示在地图上，而且我找不到任何编程错误:

I am trying to use a MapPolyLine in my Map to show a real-time route, hopefully it will move/scale this time. The thing is the line is not being shown on the map, and I cannot find any programming mistake:

C#

MapLayer pathLayer;

//Constructor
 pathLayer = new MapLayer();
 MapPolyline line = new MapPolyline();
 line.StrokeColor = Colors.Red;
 line.StrokeThickness = 10;
 //line.Path.Add(several points); Tested, no effect
 MapOverlay overlay = new MapOverlay();
 overlay.Content = line;
 //overlay.GeoCoordinate = new GeoCoordinate(0,0); Tested, no effect
 //overlay.PositionOrigin = new Point(0.0, 1.0); Tested, no effect
 pathLayer.Add(overlay);
 MyMap.Layers.Add(pathLayer);


void geolocator_PositionChanged(Geolocator sender, PositionChangedEventArgs args)
{
  MapPolyline line = pathLayer.First(TrackPath).Content as MapPolyline;
  line.Path.Add(args.Position.Coordinate); // Checked values, line.Path adds them correctly
}

新信息.尝试使用XAML进行添加时，模拟器显示错误，并且模拟器在地图顶部以图形故障的形式显示类的名称:

New info. The emulator shows an error when trying to add it using XAML, and the emulator shows the name of the class on the top of the map as a graphic glitch:

推荐答案

MapPolylines和MapPolygons应该添加到MapElements集合中，而不是MapLayer或MapOverlay.

MapPolylines and MapPolygons should be added to the MapElements collection... not a MapLayer or a MapOverlay.

您应该能够使此示例为您工作.

You should be able to make this example work for you.

        MapPolyline line = new MapPolyline();
        line.StrokeColor = Colors.Red;
        line.StrokeThickness = 10;
        line.Path.Add(new GeoCoordinate(47.6602, -122.098358));
        line.Path.Add(new GeoCoordinate(47.561482, -122.071544));
        MyMap.MapElements.Add(line);

在GeoCoord观察器中，您必须从地图的MapElements集合中获取线，并将新位置添加到线的路径中，而不是像我一样预先定义.这应该可行.

In your GeoCoord watcher you'll have to get the line from the map's MapElements collection, and add the new position to the line's path instead of predefining like I did. This should be doable.

这篇关于未绘制MapPolyline的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！