Bug 1595 - Error window opens up with message "Unhandled exception" when try to select other file from file tab.
Summary: Error window opens up with message "Unhandled exception" when try to select o...
Alias: None
Product: Xamarin Studio
Classification: Desktop
Component: General ()
Version: 2.8.1
Hardware: Macintosh Mac OS
: Low major
Target Milestone: ---
Assignee: Mike Krüger
Depends on:
Reported: 2011-10-20 05:03 UTC by narayanp
Modified: 2013-05-29 12:04 UTC (History)
7 users (show)

Is this bug a regression?: ---
Last known good build:

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Description narayanp 2011-10-20 05:03:55 UTC
Step to Reproduce:

1. Launch the Mono Develop and create a application.
2. Open two files. Split both the files from Window<<Split Vertically.
3. Click on "Switch between split" on any file.
4. Double click between the dividing line to unsplit the file.
5. Again Split the same file vertically and click on "Switch between split" option.
6. Now try to select the other file from the file tab

Actual result:
Error window opens up with message "Unhandled exception" when try to select other file from file tab.
(System.NullReferenceException: Object reference not set to an instance of an object
  at MonoDevelop.Ide.Navigation.NavigationHistoryService.DetachFromCurrentDoc () [0x00030] in /private/tmp/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Navigation/NavigationHistoryService.cs:273 
  at MonoDevelop.Ide.Navigation.NavigationHistoryService.AttachToDoc (MonoDevelop.Ide.Gui.Document document) [0x00000] in /private/tmp/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Navigation/NavigationHistoryService.cs:247 
  at MonoDevelop.Ide.Navigation.NavigationHistoryService.ActiveDocChanged (System.Object sender, System.EventArgs args) [0x00006] in /private/tmp/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Navigation/NavigationHistoryService.cs:242 
  at (wrapper delegate-invoke) <Module>:invoke_void__this___object_EventArgs (object,System.EventArgs)
  at MonoDevelop.Ide.Gui.Workbench.OnDocumentChanged (System.Object s, System.EventArgs a) [0x0000b] in /private/tmp/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Gui/Workbench.cs:559 
  at MonoDevelop.Ide.Gui.DefaultWorkbench.OnActiveWindowChanged (System.Object sender, System.EventArgs e) [0x00075] in /private/tmp/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Gui/DefaultWorkbench.cs:713 
  at Gtk.Notebook.SwitchPageSignalCallback (IntPtr arg0, IntPtr arg1, UInt32 arg2, IntPtr gch) [0x00000] in <filename unknown>:0 )

Expected Result:
Error window should not open and user should able to select the other file from file tab.

Mono Develop - 2.8.1
MonoTouch- 5.0
Mono Framework - 2.6
Comment 1 Sebastien Pouliot 2011-10-20 11:41:54 UTC
-> monodevelop
Comment 2 Mike Krüger 2012-03-30 09:22:21 UTC
Comment 3 Akhilesh kumar 2013-05-29 12:04:39 UTC
Today we have checked this issue on following builds:

XS 4.0.8(build 2)
Mono 2.10.12

We are not able to find option "Split Vertically" under windows menu in current XS.

Hence changing its status to verified.