多个窗体(MDI)同时展示,并相互操作这并不困难,小弟在这介绍一下由MapInfo中MapControl组成的多窗体关联处理。


首先看看效果:


LongLLMLinguaPostprocessor的model_config参数_Code

 


以上多关联地图窗体实现了:在同一个窗体中加载多个(最多4个)地图,地图的拖拽、缩放操作可相互关联,每个地图上各个数据都可以完全不相同!


 

现在我来说一下实现过程:


首先要在同一个窗体中加载多个地图,我采用了UserControl来做:


public partial class ViewMap :System.Windows.Forms.UserControl 

 

  在这个ViewMap控件中,我把地图控件所需要的所有东西(包括加载数据的方法、展示图元的方法等)都封装其中。 

 
 
  声明事件 
  
 <!-- 
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        /**//// <summary>
        /// 传递子控件事件到父窗体的中间事件
        /// </summary>
        public event MouseEventHandler MapControl_MouseMove;
        /**//// <summary>
        /// 传递子控件事件到父窗体的中间事件
        /// </summary>
        public event EventHandler ViewChanged;
        /**//// <summary>
        /// 控件关闭事件
        /// </summary>
        public event EventHandler Closed;
        /**//// <summary>
        /// 在地图控件上点击后触发
        /// </summary>
        public event MouseEventHandler MapControl_MouseClick;
 

  由于在ViewMap中的MapControl是私有的,MapControl的事件并不能被外界所调用,所以在此声明两个用于传递事件的中间事件,以使各地图控件相互关联操作。当然,这些MapControl的事件需要在ViewMap中注册并调用: 

 
  转发事件  
 <!--  Code highlighting produced by Actipro CodeHighlighter (freeware)
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        void mapControl1_MapControl_MouseMove ( object sender, MouseEventArgs e )
        
{
            if ( this.MapControl_MouseMove != null )
            
{
                //把事件转发出去
                MapControl_MouseMove ( this, e );
            }
        }
        void mapControl1_MapControl_MouseClick ( object sender, MouseEventArgs e )
        
{
            if ( this.MapControl_MouseClick != null )
            
{
                MapControl_MouseClick ( this, e );
            }
        }
 

  在以上代码中,需要注意到是,我在调用MapControl_MouseMove事件时,把sender的参数转换为了ViewMap本身,这样做,是为了将来避免死循环。 

 
   添加子控件   
 <!--   Code highlighting produced by Actipro CodeHighlighter (freeware)
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         /**//// <summary>
        /// 为窗体添加子控件
        /// </summary>
        /// <param name="childForm">需要添加的子窗体</param>
        public void AddChildForm ( ViewMap childForm )
        
{
            if ( !childFormList.Contains ( childForm ) )
            
{
                if ( !( childFormList.Count + 1 > _maxChildForm ) )
                
{
                    this.childFormList.Add ( childForm );
                }
                else
                
{
                    MessageBox.Show ( _OVER_MAX_CHILDFORM_COUNT );
                    return;
                }
            }
            childForm.MapControl_MouseMove += new MouseEventHandler ( vm_MapControl_MouseMove );
            childForm.ViewChanged += new EventHandler ( vm_ViewChanged );
            childForm.Closed += new EventHandler ( childForm_Closed );
            childForm.MapControl_MouseClick += new MouseEventHandler ( childForm_MapControl_MouseClick );
            SetChildFormLocation ();
            this.Controls.Add ( childForm );
        }
 
   执行方法节选   
 <!--   Code highlighting produced by Actipro CodeHighlighter (freeware)
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         void vm_MapControl_MouseMove ( object sender, MouseEventArgs e )
        
{
            foreach ( ViewMap vm in childFormList )
            
{
                if ( !sender.Equals ( vm ) )
                
{
                    vm.DrawAssistLine ( e.Location );
                }
            }
        }

        void vm_ViewChanged ( object sender, EventArgs e )
        
{
            //遍历所有子窗体,如当前sender不为本身,执行事件
            MapControlEventArg mce = e as MapControlEventArg;
            foreach ( ViewMap vm in childFormList )
            
{
                if ( !sender.Equals ( vm ) )
                
{
                    vm.SetCenter ( mce.ZoomLevel, mce.Center );
                }
            }
        }

在这里,就可以看出来使用ViewMap本身替代sender的优点了,在这里循环判断一下子控件列表,如果不为控件本身,便执行相应方法……