我正在编写一个使用 GMapControl 的 WPF 程序。我想允许用户点击地图并在用户点击的地方添加一个标记。我不想使用“MouseUp”和“MouseDown”事件,以便仅在用户实际单击地图并忽略拖放时才会捕获该事件。另外,我希望能够以同样的方式捕捉手写笔和触摸事件。我注意到没有“点击”事件。对于如何做到这一点,还有其他最佳实践吗?
谢谢,
似乎已经晚了,但我这样做的方式是创建一个集合,该集合将处理多边形到 MapControl 和事件的渲染。首先是创建一个可以扩展的多边形基类。
public abstract class BasePolygon : GMapPolygon
{
public BasePolygon() : base(new List<PointLatLng>())
{
}
public virtual void Render(Map map)
{
//code for displaying polygons on map goes here, basically
map.Markers.Add(this);
}
public virtual void Derender(Map map)
{
//code for removing polygons on map goes here, basically
map.Markers.Remove(this);
}
}
然后创建一个集合,作为一个层来处理我们的多边形和它的事件。它的行为类似于具有属性和事件的ListBox
or 。ListView
SelectedItem
SelectionChanged
public abstract class BasePolygonList : List<BasePolygon>
{
private BasePolygon SelectedItem_;
public BasePolygon SelectedItem
{
get
{
return this.SelectedItem_;
}
set
{
this.SelectedItem_ = value;
//fire the event when a polygon is 'clicked'
this.OnSelectionChanged();
}
}
protected Map map;
public BasePolygonList(Map map)
{
this.map = map;
}
//The Event which will fire if a polygon is clicked
public event EventHandler SelectionChanged = delegate { };
public void OnSelectionChanged()
{
if (this.SelectionChanged == null) return;
this.SelectionChanged(this, new EventArgs());
}
//Render our polygons on the Map Control
public void Render()
{
foreach(BasePolygon poly in this)
{
//Draw the polygon on the map
poly.Render(this.map);
//Enable the HitTest of the polygon
poly.Shape.IsHitTestVisible = true;
//Attach the Click Event at the polygon
((FrameworkElement)poly.Shape).MouseDown += (sender, e) =>
{
//Make sure that the Left Mouse Button is the one clicked
if(e.LeftButton == System.Windows.Input.MouseButtonState.Pressed)
//Set the the current polygon on the foreach as the Selected item
//It will also fire the SelectionChanged event
this.SelectedItem = poly;
};
}
}
}
BasePolygonList polygonCollection = new BasePolygonList(MapControl);
//add your polygons here
//add your polygons here
//add your polygons here
//Display the polygons on the MapControl
polygonCollection.Render();
//do something when a polygon is clicked
polygonCollection.SelectionChanged += (s,e) =>
{
Console.WriteLine("A polygon is Clicked/Selected");
//get the object instance of the selected polygon
BasePolygon SelectedPoly = polygonCollection.SelectedItem;
};
您还可以继承BasePolygon
该类以满足您的需求。例如
public class RealProperty : BasePolygon
{
public string OwnerName { get; set; }
public decimal Area { get; set; }
public decimal MarketValue { get; set; }
}
BasePolygonList RealPropertyCollection = new BasePolygonList(MapControl);
//create our polygon with data
//don't forget to add the vertices
RealProperty RealPropertyItem1 = new RealProperty()
{
OwnerName = "Some Owner Name",
Area = 1000,
MarketValue = 650000
};
//Add the created polygon to the list
RealPropertyCollection.Add(RealPropertyItem1);
//Display the polygons on the MapControl
RealPropertyCollection.Render();
//do something when a polygon is clicked
RealPropertyCollection.SelectionChanged += (s,e) =>
{
//get the object instance of the selected polygon
RealProperty SelectedPoly = (RealProperty)RealPropertyCollection.SelectedItem;
//Display the data
Console.WriteLine("Owner Name: " + SelectedPoly.OwnerName);
Console.WriteLine("Area: " + SelectedPoly.Area);
Console.WriteLine("MarketValue : " + SelectedPoly.MarketValue );
};
您可以从以下链接获得答案
点击 [这里] ( https://github.com/radioman/greatmaps )
注意 CustomMarkerDemo.xaml.cs 并将其添加到您的程序中。此自定义标记具有您需要的点击事件。
Well, if there is no Click
event, you're going to have to handle MouseDown
+ MouseUp
to detect clicks. Just store the e.Position
in MouseDown
, and in MouseUp
, compare to make sure the mouse hasn't moved much:
private Point downPoint;
private void OnMouseDown(object sender, MouseButtonEventArgs e)
{
downPoint = e.Position;
}
private void OnMouseUp(Object sender, MouseButtonEventArgs e)
{
if (Math.Abs(downPoint.X - e.Position.X) < SystemParameters.MinimumHorizontalDragDistance &&
Math.Abs(downPoint.Y - e.Position.Y) < SystemParameters.MinimumVerticalDragDistance)
{
HandleClick(sender, e);
}
}
You'd need to do something similar for stylus and touch support.