《ArcGIS Engine+C#实例开发教程》第三讲 MapControl与PageLayoutControl同步

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原文:《ArcGIS Engine+C#实例开发教程》第三讲 MapControl与PageLayoutControl同步

摘要:在ArcMap中,能够很方面地进行MapView和LayoutView两种视图的切换,而且二者之间的数据是同步显示的。关于两种视图同步的实现方法有多种,可以使用ObjectCopy对象进行数据硬拷贝,而比较简单的方法莫过于二者共享一份地图了,这也是最常用的方法。

 教程目录:

第一讲 桌面GIS应用程序框架的建立

第二讲 菜单的添加及其实现

第三讲 MapControl与PageLayoutControl同步

第四讲 状态栏信息的添加与实现

第五讲 鹰眼的实现

第六讲 右键菜单添加与实现

教程Bug及优化方案1

第七讲 图层符号选择器的实现1

第七讲 图层符号选择器的实现2

第八讲 属性数据表的查询显示

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在ArcMap中,能够很方面地进行MapView和Layout View两种视图的切换,而且二者之间的数据是同步显示的。
关于两种视图同步的实现方法有多种,可以使用ObjectCopy对象进行数据硬拷贝,而比较简单的方法莫过于二者共享一份地图了,这也是最常用的方法。


1、新建同步类ControlsSynchronizer

 
在解决方案面板中右击项目名,选择“添加|类”,在类别中选择“Visual C#项目项”,在模板中选择“类”,输入类名“ControlsSynchronizer.cs”,将以下代码覆盖自动生成的代码:

 

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.IO;
using System.Runtime.InteropServices;

using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.SystemUI;

namespace _sdnMap
{
    /// <summary>
    /// This class is used to synchronize a gven PageLayoutControl and a MapControl.
    /// When initialized, the user must pass the reference of these control to the class, bind
    /// the control together by calling ‘BindControls‘ which in turn sets a joined Map referenced
    /// by both control; and set all the buddy controls joined between these two controls.
    /// When alternating between the MapControl and PageLayoutControl, you should activate the visible control
    /// and deactivate the other by calling ActivateXXX.
    /// This calss is limited to a situation where the controls are not simultaneously visible.
    /// </summary>
    public class ControlsSynchronizer
    {
        #region class members
        private IMapControl3 m_mapControl = null;
        private IPageLayoutControl2 m_pageLayoutControl = null;
        private ITool m_mapActiveTool = null;
        private ITool m_pageLayoutActiveTool = null;
        private bool m_IsMapCtrlactive = true;

        private ArrayList m_frameworkControls = null;
        #endregion

        #region constructor

        /// <summary>
        /// 默认构造函数
        /// </summary>
        public ControlsSynchronizer()
        {
            //初始化ArrayList
            m_frameworkControls = new ArrayList();
        }

        /// <summary>
        /// 构造函数
        /// </summary>
        /// <param name="mapControl"></param>
        /// <param name="pageLayoutControl"></param>
        public ControlsSynchronizer(IMapControl3 mapControl, IPageLayoutControl2 pageLayoutControl)
            : this()
        {
            //为类成员赋值
            m_mapControl = mapControl;
            m_pageLayoutControl = pageLayoutControl;
        }
        #endregion

        #region properties
        /// <summary>
        /// 取得或设置MapControl
        /// </summary>
        public IMapControl3 MapControl
        {
            get { return m_mapControl; }
            set { m_mapControl = value; }
        }

        /// <summary>
        /// 取得或设置PageLayoutControl
        /// </summary>
        public IPageLayoutControl2 PageLayoutControl
        {
            get { return m_pageLayoutControl; }
            set { m_pageLayoutControl = value; }
        }

        /// <summary>
        /// 取得当前ActiveView的类型
        /// </summary>
        public string ActiveViewType
        {
            get
            {
                if (m_IsMapCtrlactive)
                    return "MapControl";
                else
                    return "PageLayoutControl";
            }
        }

        /// <summary>
        /// 取得当前活动的Control
        /// </summary>
        public object ActiveControl
        {
            get
            {
                if (m_mapControl == null || m_pageLayoutControl == null)
                   throw new Exception("ControlsSynchronizer::ActiveControl:\\r\\nEitherMapControl or PageLayoutControl are not initialized!");

                if (m_IsMapCtrlactive)
                    return m_mapControl.Object;
                else
                    return m_pageLayoutControl.Object;
            }
        }
        #endregion

        #region Methods
        /// <summary>
        /// 激活MapControl并解除the PagleLayoutControl
        /// </summary>
        public void ActivateMap()
        {
            try
            {
                if (m_pageLayoutControl == null || m_mapControl == null)
                   throw new Exception("ControlsSynchronizer::ActivateMap:\\r\\nEitherMapControl or PageLayoutControl are not initialized!");

                //缓存当前PageLayout的CurrentTool
                if (m_pageLayoutControl.CurrentTool != null) m_pageLayoutActiveTool = m_pageLayoutControl.CurrentTool;

                //解除PagleLayout
                m_pageLayoutControl.ActiveView.Deactivate();

               //激活MapControl
                m_mapControl.ActiveView.Activate(m_mapControl.hWnd);

                //将之前MapControl最后使用的tool,作为活动的tool,赋给MapControl的CurrentTool
                if (m_mapActiveTool != null) m_mapControl.CurrentTool = m_mapActiveTool;

                m_IsMapCtrlactive = true;

                //为每一个的framework controls,设置Buddy control为MapControl
                this.SetBuddies(m_mapControl.Object);
            }
            catch (Exception ex)
            {
                throw new Exception(string.Format("ControlsSynchronizer::ActivateMap:\\r\\n{0}", ex.Message));
            }
        }

        /// <summary>
        /// 激活PagleLayoutControl并减活MapCotrol
        /// </summary>
        public void ActivatePageLayout()
        {
            try
            {
                if (m_pageLayoutControl == null || m_mapControl == null)
                   throw newException("ControlsSynchronizer::ActivatePageLayout:\\r\\nEitherMapControl or PageLayoutControl are not initialized!");

                //缓存当前MapControl的CurrentTool
                if (m_mapControl.CurrentTool != null) m_mapActiveTool = m_mapControl.CurrentTool;

                //解除MapControl
                m_mapControl.ActiveView.Deactivate();

                //激活PageLayoutControl
                m_pageLayoutControl.ActiveView.Activate(m_pageLayoutControl.hWnd);

                //将之前PageLayoutControl最后使用的tool,作为活动的tool,赋给PageLayoutControl的CurrentTool
                if (m_pageLayoutActiveTool != null) m_pageLayoutControl.CurrentTool = m_pageLayoutActiveTool;

                m_IsMapCtrlactive = false;

                //为每一个的framework controls,设置Buddy control为PageLayoutControl
                this.SetBuddies(m_pageLayoutControl.Object);
            }
            catch (Exception ex)
            {
                throw new Exception(string.Format("ControlsSynchronizer::ActivatePageLayout:\\r\\n{0}", ex.Message));
            }
        }

        /// <summary>
        /// 给予一个地图, 置换PageLayoutControl和MapControl的focus map
        /// </summary>
        /// <param name="newMap"></param>
        public void ReplaceMap(IMap newMap)
        {
            if (newMap == null)
                throw new Exception("ControlsSynchronizer::ReplaceMap:\\r\\nNew map for replacement is not initialized!");

            if (m_pageLayoutControl == null || m_mapControl == null)
               throw new Exception("ControlsSynchronizer::ReplaceMap:\\r\\nEitherMapControl or PageLayoutControl are not initialized!");

            //create a new instance of IMaps collection which is needed by the PageLayout
            //创建一个PageLayout需要用到的,新的IMaps collection的实例
            IMaps maps = new Maps();
            //add the new map to the Maps collection
            //把新的地图加到Maps collection里头去
            maps.Add(newMap);

            bool bIsMapActive = m_IsMapCtrlactive;

            //call replace map on the PageLayout in order to replace the focus map
            //we must call ActivatePageLayout, since it is the control we call ‘ReplaceMaps‘
            //调用PageLayout的replace map来置换focus map
            //我们必须调用ActivatePageLayout,因为它是那个我们可以调用"ReplaceMaps"的Control
            this.ActivatePageLayout();
            m_pageLayoutControl.PageLayout.ReplaceMaps(maps);

            //assign the new map to the MapControl
            //把新的地图赋给MapControl
            m_mapControl.Map = newMap;

            //reset the active tools
            //重设active tools
            m_pageLayoutActiveTool = null;
            m_mapActiveTool = null;

            //make sure that the last active control is activated
            //确认之前活动的control被激活
            if (bIsMapActive)
            {
                this.ActivateMap();
                m_mapControl.ActiveView.Refresh();
            }
            else
            {
                this.ActivatePageLayout();
                m_pageLayoutControl.ActiveView.Refresh();
            }
        }

        /// <summary>
        /// bind the MapControl and PageLayoutControl together by assigning a new joint focus map
        /// 指定共同的Map来把MapControl和PageLayoutControl绑在一起
        /// </summary>
        /// <param name="mapControl"></param>
        /// <param name="pageLayoutControl"></param>
       /// <param name="activateMapFirst">true if the MapControlsupposed to be activated first,如果MapControl被首先激活,则为true</param>
        public void BindControls(IMapControl3 mapControl, IPageLayoutControl2 pageLayoutControl, bool activateMapFirst)
        {
            if (mapControl == null || pageLayoutControl == null)
               throw new Exception("ControlsSynchronizer::BindControls:\\r\\nEitherMapControl or PageLayoutControl are not initialized!");

            m_mapControl = MapControl;
            m_pageLayoutControl = pageLayoutControl;

            this.BindControls(activateMapFirst);
        }

        /// <summary>
        /// bind the MapControl and PageLayoutControl together by assigning a new joint focus map
        /// 指定共同的Map来把MapControl和PageLayoutControl绑在一起
        /// </summary>
       /// <param name="activateMapFirst">true if the MapControlsupposed to be activated first,如果MapControl被首先激活,则为true</param>
        public void BindControls(bool activateMapFirst)
        {
            if (m_pageLayoutControl == null || m_mapControl == null)
               throw new Exception("ControlsSynchronizer::BindControls:\\r\\nEitherMapControl or PageLayoutControl are not initialized!");

            //create a new instance of IMap
            //创造IMap的一个实例
            IMap newMap = new MapClass();
            newMap.Name = "Map";

            //create a new instance of IMaps collection which is needed by the PageLayout
            //创造一个新的IMaps collection的实例,这是PageLayout所需要的
            IMaps maps = new Maps();
            //add the new Map instance to the Maps collection
            //把新的Map实例赋给Maps collection
            maps.Add(newMap);

            //call replace map on the PageLayout in order to replace the focus map
            //调用PageLayout的replace map来置换focus map
            m_pageLayoutControl.PageLayout.ReplaceMaps(maps);
            //assign the new map to the MapControl
            //把新的map赋给MapControl
            m_mapControl.Map = newMap;

            //reset the active tools
            //重设active tools
            m_pageLayoutActiveTool = null;
            m_mapActiveTool = null;

            //make sure that the last active control is activated
            //确定最后活动的control被激活
            if (activateMapFirst)
                this.ActivateMap();
            else
                this.ActivatePageLayout();
        }

        /// <summary>
        ///by passing the application‘s toolbars and TOC to the synchronization class, it saves you the
        ///management of the buddy control each time the active control changes. This method ads the framework
        ///control to an array; once the active control changes, the class iterates through the array and
        ///calles SetBuddyControl on each of the stored framework control.
        /// </summary>
        /// <param name="control"></param>
        public void AddFrameworkControl(object control)
        {
            if (control == null)
                throw new Exception("ControlsSynchronizer::AddFrameworkControl:\\r\\nAdded control is not initialized!");

            m_frameworkControls.Add(control);
        }

        /// <summary>
        /// Remove a framework control from the managed list of controls
        /// </summary>
        /// <param name="control"></param>
        public void RemoveFrameworkControl(object control)
        {
            if (control == null)
               throw newException("ControlsSynchronizer::RemoveFrameworkControl:\\r\\nControl tobe removed is not initialized!");

            m_frameworkControls.Remove(control);
        }

        /// <summary>
        /// Remove a framework control from the managed list of controls by specifying its index in the list
        /// </summary>
        /// <param name="index"></param>
        public void RemoveFrameworkControlAt(int index)
        {
            if (m_frameworkControls.Count < index)
                throw new Exception("ControlsSynchronizer::RemoveFrameworkControlAt:\\r\\nIndex is out of range!");

            m_frameworkControls.RemoveAt(index);
        }

        /// <summary>
        /// when the active control changes, the class iterates through the array of the framework controls
        ///  and calles SetBuddyControl on each of the controls.
        /// </summary>
        /// <param name="buddy">the active control</param>
        private void SetBuddies(object buddy)
        {
            try
            {
                if (buddy == null)
                    throw new Exception("ControlsSynchronizer::SetBuddies:\\r\\nTarget Buddy Control is not initialized!");

                foreach (object obj in m_frameworkControls)
                {
                    if (obj is IToolbarControl)
                    {
                        ((IToolbarControl)obj).SetBuddyControl(buddy);
                    }
                    else if (obj is ITOCControl)
                    {
                        ((ITOCControl)obj).SetBuddyControl(buddy);
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception(string.Format("ControlsSynchronizer::SetBuddies:\\r\\n{0}", ex.Message));
            }
        }
        #endregion
    }
}

2、新建Maps类

在同步类中,要用到Maps类,用于管理地图对象。与新建同步类ControlsSynchronizer类似,我们新建一Maps类,其所有代码如下所示:

 

 using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;

using ESRI.ArcGIS.Carto;

namespace _sdnMap
{
    [Guid("f27d8789-fbbc-4801-be78-0e3cd8fff9d5")]
    [ClassInterface(ClassInterfaceType.None)]
    [ProgId("_sdnMap.Maps")]
    public class Maps : IMaps, IDisposable
    {
        //class member - using internally an ArrayList to manage the Maps collection
        private ArrayList m_array = null;

        #region class constructor
        public Maps()
        {
            m_array = new ArrayList();
        }
        #endregion

        #region IDisposable Members

        /// <summary>
        /// Dispose the collection
        /// </summary>
        public void Dispose()
        {
            if (m_array != null)
            {
                m_array.Clear();
                m_array = null;
            }
        }

        #endregion

        #region IMaps Members

        /// <summary>
        /// Remove the Map at the given index
        /// </summary>
        /// <param name="Index"></param>
        public void RemoveAt(int Index)
        {
            if (Index > m_array.Count || Index < 0)
                throw new Exception("Maps::RemoveAt:\\r\\nIndex is out of range!");

            m_array.RemoveAt(Index);
        }

        /// <summary>
        /// Reset the Maps array
        /// </summary>
        public void Reset()
        {
            m_array.Clear();
        }

        /// <summary>
        /// Get the number of Maps in the collection
        /// </summary>
        public int Count
        {
            get
            {
                return m_array.Count;
            }
        }

        /// <summary>
        /// Return the Map at the given index
        /// </summary>
        /// <param name="Index"></param>
        /// <returns></returns>
        public IMap get_Item(int Index)
        {
            if (Index > m_array.Count || Index < 0)
                throw new Exception("Maps::get_Item:\\r\\nIndex is out of range!");

            return m_array[Index] as IMap;
        }

        /// <summary>
        /// Remove the instance of the given Map
        /// </summary>
        /// <param name="Map"></param>
        public void Remove(IMap Map)
        {
            m_array.Remove(Map);
        }

        /// <summary>
        /// Create a new Map, add it to the collection and return it to the caller
        /// </summary>
        /// <returns></returns>
        public IMap Create()
        {
            IMap newMap = new MapClass();
            m_array.Add(newMap);

            return newMap;
        }

        /// <summary>
        /// Add the given Map to the collection
        /// </summary>
        /// <param name="Map"></param>
        public void Add(IMap Map)
        {
            if (Map == null)
                throw new Exception("Maps::Add:\\r\\nNew Map is mot initialized!");

            m_array.Add(Map);
        }

        #endregion
    }
}


3、新建打开文档类OpenNewMapDocument

 
由于从工具栏自带的打开按钮打开地图文档的时候,不会自动进行两种视图之间的同步,所以我们要自己派生一个OpenNewMapDocument类,用于打开地图文档。
 右击项目名,选择“添加|类”,再选择ArcGIS类别中的BaseCommand模板,输入类名为“OpenNewMapDocument.cs”。
首先添加引用:

 

using System.Windows.Forms;
using ESRI.ArcGIS.Carto;

再添加如下成员变量:

 

 private ControlsSynchronizer m_controlsSynchronizer = null;

修改默认的构造函数如下所示:

 

 //添加参数
public OpenNewMapDocument(ControlsSynchronizer controlsSynchronizer)
        {
            //
            // TODO: Define values for the public properties
            //
//设定相关属性值
            base.m_category = "Generic"; //localizable text
            base.m_caption = "Open";  //localizable text
            base.m_message = "This should work in ArcMap/MapControl/PageLayoutControl";  //localizable text
            base.m_toolTip = "Open";  //localizable text
            base.m_name = "Generic_Open";   //unique id, non-localizable (e.g. "MyCategory_MyCommand")
           
   //初始化m_controlsSynchronizer
            m_controlsSynchronizer = controlsSynchronizer;

            try
            {
                //
                // TODO: change bitmap name if necessary
                //
                string bitmapResourceName = GetType().Name + ".bmp";
                base.m_bitmap = new Bitmap(GetType(), bitmapResourceName);
            }
            catch (Exception ex)
            {
                System.Diagnostics.Trace.WriteLine(ex.Message, "Invalid Bitmap");
            }
        }

再在OnClick函数中添加如下代码:

 

 public override void OnClick()
        {
            // TODO: Add OpenNewMapDocument.OnClick implementation
            OpenFileDialog dlg = new OpenFileDialog();
            dlg.Filter = "Map Documents (*.mxd)|*.mxd";
            dlg.Multiselect = false;
            dlg.Title = "Open Map Document";
            if (dlg.ShowDialog() == DialogResult.OK)
            {
                string docName = dlg.FileName;

                IMapDocument mapDoc = new MapDocumentClass();
                if (mapDoc.get_IsPresent(docName) && !mapDoc.get_IsPasswordProtected(docName))
                {
                    mapDoc.Open(docName, string.Empty);
                    IMap map = mapDoc.get_Map(0);
                    m_controlsSynchronizer.ReplaceMap(map);

                    mapDoc.Close();
                }
            }
        }

在添加类时,模板会自动添加一个名为“OpenNewMapDocument.bmp”的图标,你可以自己修改或者替换为打开的文件夹的图标。

4、两种视图的同步

 
在3sdnMap.cs中添加成员变量,即同步类对象:

 

 private ControlsSynchronizer m_controlsSynchronizer = null;

在Form1_Load函数中进行初始化工作:

 

 //初始化controls synchronization calss
m_controlsSynchronizer = new
ControlsSynchronizer(m_mapControl, m_pageLayoutControl);
     //把MapControl和PageLayoutControl绑定起来(两个都指向同一个Map),然后设置MapControl为活动的Control
     m_controlsSynchronizer.BindControls(true);
     //为了在切换MapControl和PageLayoutControl视图同步,要添加Framework Control
    m_controlsSynchronizer.AddFrameworkControl(axToolbarControl1.Object);
    m_controlsSynchronizer.AddFrameworkControl(this.axTOCControl1.Object);
// 添加打开命令按钮到工具条
OpenNewMapDocument openMapDoc = new OpenNewMapDocument(m_controlsSynchronizer);
axToolbarControl1.AddItem(openMapDoc, -1, 0, false, -1, esriCommandStyles.esriCommandStyleIconOnly);


因为我们自动派生了打开文档类,并自己将其添加到工具条,所以我们就不需要工具条原来的“打开”按钮了,可以ToolbarControl的属性中将其删除。
下面,我们可完成上一讲遗留的功能了。

 

 /// <summary>
        /// 新建地图命令
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void New_Click(object sender, EventArgs e)
        {
            //询问是否保存当前地图
            DialogResult res = MessageBox.Show("是否保存当前地图?", "提示", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
            if (res == DialogResult.Yes)
            {
                //如果要保存,调用另存为对话框
                ICommand command = new ControlsSaveAsDocCommandClass();
                if (m_mapControl != null)
                    command.OnCreate(m_controlsSynchronizer.MapControl.Object);
                else
                    command.OnCreate(m_controlsSynchronizer.PageLayoutControl.Object);

                command.OnClick();
            }
     //创建新的地图实例
            IMap map = new MapClass();
            map.Name = "Map";
            m_controlsSynchronizer.MapControl.DocumentFilename = string.Empty;
            //更新新建地图实例的共享地图文档
            m_controlsSynchronizer.ReplaceMap(map);
        }

 

/// <summary>
        /// 打开地图文档Mxd命令
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Open_Click(object sender, EventArgs e)
        {
if (this.axMapControl1.LayerCount > 0)
            {
                DialogResult result = MessageBox.Show("是否保存当前地图?", "警告",
MessageBoxButtons.YesNoCancel, MessageBoxIcon.Question);
                if (result == DialogResult.Cancel) return;
                if (result == DialogResult.Yes) this.Save_Click(null, null);
            }
            OpenNewMapDocument openMapDoc =
new OpenNewMapDocument(m_controlsSynchronizer);
            openMapDoc.OnCreate(m_controlsSynchronizer.MapControl.Object);
            openMapDoc.OnClick();
}

在添加数据AddData时,我们也要进行地图共享,故在AddData_Click函数后面添加如下代码:

 

 IMap pMap = this.axMapControl1.Map;
this.m_controlsSynchronizer.ReplaceMap(pMap);

在另存为地图文档时,有可能会丢失数据,因此我们需要提示用户以确认操作,故需修改SaveAs_Click函数,如下所示:

 

 /// <summary>
        /// 另存为地图文档命令
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void SaveAs_Click(object sender, EventArgs e)
        {
            //如果当前视图为MapControl时,提示用户另存为操作将丢失PageLayoutControl中的设置
            if (m_controlsSynchronizer.ActiveControl is IMapControl3)
            {
               if (MessageBox.Show("另存为地图文档将丢失制版视图的设置\\r\\n您要继续吗?", "提示",MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.No)
                    return;
            }

            //调用另存为命令
            ICommand command = new ControlsSaveAsDocCommandClass();
            command.OnCreate(m_controlsSynchronizer.ActiveControl);
            command.OnClick();
        }

在切换视图时,我们要激活相关的视图,故在设计视图的属性面板中选择tabControl2控件,再选择事件按钮,找到“SelectedIndexChanged”事件双击添加之。其实现代码如下所示:

 

 /// <summary>
        /// 切换地图和制版视图
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void tabControl2_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (this.tabControl2.SelectedIndex == 0)
            {
                //激活MapControl
                m_controlsSynchronizer.ActivateMap();
            }
            else
            {
                //激活PageLayoutControl
                m_controlsSynchronizer.ActivatePageLayout();
            }
        }


5、编译运行

 
按F5编译运行程序,至此我们完成了MapControl和PageLayoutControl两种视图的同步工作。

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