Custom map navigation commands
FixedZoomOut.cs
// Copyright 2012 ESRI
// 
// All rights reserved under the copyright laws of the United States
// and applicable international laws, treaties, and conventions.
// 
// You may freely redistribute and use this sample code, with or
// without modification, provided you include the original copyright
// notice and use restrictions.
// 
// See the use restrictions.
// 

using System;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.SystemUI;
using ESRI.ArcGIS.ADF.CATIDs;
using System.Runtime.InteropServices;

namespace PanZoom
{
  [ClassInterface(ClassInterfaceType.None)]
  [Guid("B50CB8E7-1CD0-41d3-8C89-4CD8969E802F")]

  public class FixedZoomOut : ICommand
  {
        #region COM Registration Function(s)
        [ComRegisterFunction()]
        [ComVisible(false)]
        static void RegisterFunction(Type registerType)
        {
            // Required for ArcGIS Component Category Registrar support
            ArcGISCategoryRegistration(registerType);

            //
            // TODO: Add any COM registration code here
            //
        }

        [ComUnregisterFunction()]
        [ComVisible(false)]
        static void UnregisterFunction(Type registerType)
        {
            // Required for ArcGIS Component Category Registrar support
            ArcGISCategoryUnregistration(registerType);

            //
            // TODO: Add any COM unregistration code here
            //
        }

        #region ArcGIS Component Category Registrar generated code
        /// <summary>
        /// Required method for ArcGIS Component Category registration -
        /// Do not modify the contents of this method with the code editor.
        /// </summary>
        private static void ArcGISCategoryRegistration(Type registerType)
        {
            string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
            ControlsCommands.Register(regKey);

        }
        /// <summary>
        /// Required method for ArcGIS Component Category unregistration -
        /// Do not modify the contents of this method with the code editor.
        /// </summary>
        private static void ArcGISCategoryUnregistration(Type registerType)
        {
            string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
            ControlsCommands.Unregister(regKey);

        }

        #endregion
        #endregion

        [DllImport("gdi32.dll")]
    static extern bool DeleteObject(IntPtr hObject);

    private bool m_enabled;
    private System.Drawing.Bitmap m_bitmap;
    private IntPtr m_hBitmap;
    private IHookHelper m_pHookHelper;

    public FixedZoomOut()
    {
      string[] res = GetType().Assembly.GetManifestResourceNames();
      if(res.GetLength(0) > 0)
      {
        m_bitmap = new System.Drawing.Bitmap(GetType().Assembly.GetManifestResourceStream(GetType(), "zoomoutfxd.bmp"));
        if(m_bitmap != null)
        {
          m_bitmap.MakeTransparent(m_bitmap.GetPixel(1,1));
          m_hBitmap = m_bitmap.GetHbitmap();
        }
      }
      m_pHookHelper = new HookHelperClass ();
    }
    
    ~FixedZoomOut()
    {
      if(m_hBitmap.ToInt32() != 0)
        DeleteObject(m_hBitmap);
    }
  
    #region ICommand Members

    public void OnClick()
    {
      //Get IActiveView interface
      IActiveView pActiveView = (IActiveView) m_pHookHelper.FocusMap;

      //Get IEnvelope interface
      IEnvelope pEnvelope = (IEnvelope) pActiveView.Extent;

      //Expand envelope and refresh the view
      pEnvelope.Expand (1.25, 1.25, true);
      pActiveView.Extent = pEnvelope;
      pActiveView.Refresh();
    }

    public string Message
    {
      get
      {
        return "Zoom out from the center of the map";
      }
    }

    public int Bitmap
    {
      get
      {
        return m_hBitmap.ToInt32();
      }
    }

    public void OnCreate(object hook)
    {
      m_pHookHelper.Hook = hook;
      m_enabled = true;
    }

    public string Caption
    {
      get
      {
        return "Fixed Zoom Out";
      }
    }

    public string Tooltip
    {
      get
      {
        return "Fixed Zoom Out";
      }
    }

    public int HelpContextID
    {
      get
      {
        // TODO:  Add FixedZoomOut.HelpContextID getter implementation
        return 0;
      }
    }

    public string Name
    {
      get
      {
        return "Sample_Pan/FixedZoomOut";
      }
    }

    public bool Checked
    {
      get
      {
        return false;
      }
    }

    public bool Enabled
    {
      get
      {
        return m_enabled;
      }
    }

    public string HelpFile
    {
      get
      {
        // TODO:  Add FixedZoomOut.HelpFile getter implementation
        return null;
      }
    }

    public string Category
    {
      get
      {
        return "Sample_Pan/Zoom";
      }
    }

    #endregion
  }
}