Question

我正在向地图中心添加标记。但是，当地图的缩放级别发生变化时，中心将从“原始”地图中心移动（标记也是如此）。

无论缩放级别如何，如何以始终位于地图中心的方式绘制标记？

看起来PositionOrigin被设置为（0.5,0.5）并没有做它应该做的事情，即以画布中心位于GeoCoordinate“location”输入变量的方式绘制画布。 / p>

我绘制标记的代码如下：

    private void AddMarkerToMap( String symbol, GeoCoordinate location )
        {
        if ( _markerLayer != null )
            {
            Map1.Layers.Remove( _markerLayer );
            _markerLayer = null;
            }

        _markerLayer = new MapLayer();
        var mapCenterMarker = new MapOverlay
                            {
                                GeoCoordinate = location
                            };

        var canvas = new Canvas();
        //canvas.Opacity = 0.5;

        var circhegraphic = new Ellipse();
        circhegraphic.Fill = new SolidColorBrush( Color.FromArgb( 0x44, 0x00, 0xFF, 0x00 ) );
        circhegraphic.Stroke = new SolidColorBrush( Color.FromArgb( 0xFF, 0x00, 0x00, 0xFF ) );
        circhegraphic.StrokeThickness = 4;
        circhegraphic.Opacity = 0.7;
        circhegraphic.Height = 40;
        circhegraphic.Width = 40;
        canvas.Children.Add( circhegraphic );

        var textBlock = new TextBlock
            {
                Text = symbol,
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment = VerticalAlignment.Center,
                FontWeight = FontWeights.ExtraBold,
                Foreground = new SolidColorBrush( Color.FromArgb( 0xFF, 0xFF, 0x00, 0x00 ) )
            };
        Canvas.SetLeft( textBlock, 13 );
        Canvas.SetTop( textBlock, 4 );
        Canvas.SetZIndex( textBlock, 5 );
        canvas.Children.Add( textBlock );

        mapCenterMarker.Content = canvas;
        mapCenterMarker.PositionOrigin = new Point( 0.5, 0.5 );

        _markerLayer.Add( mapCenterMarker );
        Map1.Layers.Add( _markerLayer );
        }

谢谢，

Answer 1

问题在于Canvas，改为网格，如下所示：

    private void AddMarkerToMap( String symbol, GeoCoordinate location )
        {
        if ( _markerLayer != null )
            {
            Map1.Layers.Remove( _markerLayer );
            _markerLayer = null;
            }

        _markerLayer = new MapLayer();
        var mapCenterMarker = new MapOverlay();
        var grid = new Grid();

        var circhegraphic = new Ellipse();
        circhegraphic.Fill = new SolidColorBrush( Color.FromArgb( 0x44, 0x00, 0xFF, 0x00 ) );
        circhegraphic.Stroke = new SolidColorBrush( Color.FromArgb( 0xFF, 0x00, 0x00, 0xFF ) );
        circhegraphic.StrokeThickness = 4;
        circhegraphic.Opacity = 0.7;
        circhegraphic.Height = 40;
        circhegraphic.Width = 40;
        grid.Children.Add( circhegraphic );

        var textBlock = new TextBlock
            {
                Text = symbol,
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment = VerticalAlignment.Center,
                FontWeight = FontWeights.ExtraBold,
                FontSize = 14,
                Foreground = new SolidColorBrush( Color.FromArgb( 0xFF, 0xFF, 0x00, 0x00 ) )
            };
        grid.Children.Add( textBlock );

        mapCenterMarker.GeoCoordinate = location;
        mapCenterMarker.Content = grid;
        mapCenterMarker.PositionOrigin = new Point( 0.5, 0.5 );

        _markerLayer.Add( mapCenterMarker );
        Map1.Layers.Add( _markerLayer );
        }

虽然我不确定为什么Canvas会出问题。

无论缩放级别如何，如何以始终位于地图中心的方式绘制标记？

1 个答案: