When I tried to derive a class from SelectionMapAction and use it, ESRI code raises an exception. I checked that the constructor was being called and it was. I have tried what I can think of and I am stumped. To make sure it wasn't something specific to my map, I duplicated this issue using the "Mobile Walkthrough (10.0)" (BasicWorkThrough_Win) sample code and a different map. My code changes to the sample code are below:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using ESRI.ArcGIS.Mobile.MapActions;
namespace WindowsFormsApplication2
{
public class CustomSelectionMapAction : SelectionMapAction
{
public CustomSelectionMapAction()
: base()
{
}
public CustomSelectionMapAction(System.ComponentModel.IContainer container)
: base(container)
{
}
}
}
Then I replaced the Pan button code with:
private void Pan_Click(object sender, EventArgs e)
{
//map1.CurrentMapAction = panMapAction1;
map1.CurrentMapAction = new ESRI.ArcGIS.Mobile.MapActions.SelectionMapAction(); //line 1
map1.CurrentMapAction = new CustomSelectionMapAction(); //line 2
}
When I click the button, line 1 using the SelectionMapAction goes through fine, but line 2 using my Custom class generates this exception in esri code:
System.NullReferenceException was unhandled
Message=Object reference not set to an instance of an object.
Source=System.Windows.Forms
StackTrace:
at System.Windows.Forms.Cursor..ctor(Stream stream)
at ESRI.ArcGIS.Mobile.MapActions.SelectionMapAction.OnActiveChanging(Boolean active)
at ESRI.ArcGIS.Mobile.MapActions.MapAction.set_Active(Boolean value)
at ESRI.ArcGIS.Mobile.Map.set_CurrentMapActionIndex(Int32 value)
at ESRI.ArcGIS.Mobile.Map.set_CurrentMapAction(MapAction value)
at WindowsFormsApplication2.Form1.Pan_Click(Object sender, EventArgs e) in C:\Documents and Settings\brian.trout\Desktop\BasicWorkThrough_Win\WindowsFormsApplication2\Form1.cs:line 87
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at WindowsFormsApplication2.Program.Main() in C:\Documents and Settings\brian.trout\Desktop\BasicWorkThrough_Win\WindowsFormsApplication2\Program.cs:line 18
at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException:
Am I doing something wrong?
