Context Menu in NSTextView

Question

I am using NSTextView for the user to type their response. I have turned on continuous spell check and the incorrect words have a red line under them. I have a shared SpellChecker which I am using. But I want the user to do a right click and correct the spelling. I have the following questions -

In Text edit, as soon as you do a right click, it highlights the word, how can I achieve the same ?. I am planning to get the selectedrange and pass it to the spellchecker.
Once the spellcheck suggestions are added to the context menu, it still shows up when I go to the next word, so should I always clear the context menu before adding any new item ?.
I am using Monobjc, and when I execute the following code, I get an exception -

var t = Menu.ItemArray;

foreach(var s in t)

{

var menuItem = s.CastAs<NSMenuItem>(); //exception

}

I am basically try to get individual NSMenuItem to check if it spelling suggestions or something else.

EDIT - Added stacktrace

System.InvalidCastException: Cannot cast from source type to destination type.
  at example.test.MacOS.UI.HTML.ESView.MenuForEvent (Monobjc.Cocoa.NSEvent theEvent) [0x00000] in <filename unknown>:0 
  at Monobjc.Dynamic.Proxies.example.test.MacOS.UI.HTML.ESView.MenuForEvent_Monobjc_Cocoa_NSEvent (IntPtr receiver, IntPtr selector, IntPtr ) [0x00000] in <filename unknown>:0 
  at (wrapper native-to-managed) Monobjc.Dynamic.Proxies.example.test.MacOS.UI.HTML.ESView:MenuForEvent_Monobjc_Cocoa_NSEvent (intptr,intptr,intptr)
  at (wrapper managed-to-native) E5EEC20A:pinvoke (intptr,intptr,intptr)
  at E5EEC20A.objc_msgSendSuper (IntPtr receiver, IntPtr selector, System.Object[] parameters) [0x00000] in <filename unknown>:0 
  at Monobjc.Bridge.Generators.DynamicMessagingGenerator.SendMessage (System.String message, IntPtr receiver, IntPtr selector, System.Object[] parameters) [0x00000] in <filename unknown>:0 
  at Monobjc.ObjectiveCRuntime.SendMessageSuper (IManagedWrapper receiver, Monobjc.Class cls, System.String selector, System.Object[] parameters) [0x00000] in <filename unknown>:0 
  at Monobjc.Id.SendMessageSuper (Monobjc.Class cls, System.String selector, System.Object[] parameters) [0x00000] in <filename unknown>:0 
  at example.test.MacOS.UI.App.Application.SendEvent (Monobjc.Cocoa.NSEvent theEvent) [0x00000] in <filename unknown>:0 
  at Monobjc.Dynamic.Proxies.example.test.MacOS.UI.App.Application.SendEvent_Monobjc_Cocoa_NSEvent (IntPtr receiver, IntPtr selector, IntPtr ) [0x00000] in <filename unknown>:0 
  at (wrapper native-to-managed) Monobjc.Dynamic.Proxies.example.test.MacOS.UI.App.Application:SendEvent_Monobjc_Cocoa_NSEvent (intptr,intptr,intptr)
  at (wrapper managed-to-native) Monobjc.ObjectiveCRuntime:objc_msgSend (intptr,intptr)
  at Monobjc.ObjectiveCRuntime.SendMessage (IManagedWrapper receiver, System.String selector) [0x00000] in <filename unknown>:0 
  at Monobjc.Cocoa.NSApplication.Run () [0x00000] in <filename unknown>:0 
  at example.test.MacOS.UI.App.Application.RunApplication () [0x00000] in <filename unknown>:0 
  at example.test.MacOS.Program.Main (System.String[] args) [0x00000] in <filename unknown>:0

EDIT - Step 3

Question 3 worked based on Laurent's suggestion.

Can you try to use the "numberOfItems" and "itemAtIndex" methods within an indexed loop ? — Laurent Etiemble
@Laurent - Sure I will try that out. Also can you please suggest an answer for points 1 and 2 which I have asked above. — Prashant

Laurent Etiemble Laurent Etiemble · Accepted Answer · 2011-06-01T07:13:01

For point 1)

NSTextView.SelectedRange returns the first selected range. If no text is selected the range's length is 0 and the range's location is the index of the character where the cursor lies.
Then, get a reference to the string context (NSTextView.TextStorage.String) and search for whitespace before and after the cursor location. You will get the range for the word to select.
Use NSTextView.SelectedRange to specify the new selection range.

For point 2)

You have a total control over the Menu instance returned when a right-click is done. So if you add items to it, you have to remove them by yourself.

For point 3)

It looks like a bug. As mention in the comment, use the NumberOfItems and ItemAtIndexmethods within an indexed loop.

Context Menu in NSTextView

1 Answers