Hide advanced NSObject members to follow Xamarin.Android

[rolfbjarne]

Suggestion:

Hide members from NSObject that customers shouldn't use.

Candidates:

• Handle: https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L461
• SuperHandle: https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L446
• IntPtr constructor (never seen this constructor used): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L134
• IntPtr, bool constructor (never seen this constructor get used): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L137
• Alloc (never seen this method used): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject.iOS.cs#L31
• Init (never seen this method used): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject.iOS.cs#L36
• IsDirectBinding (required by binding code, but afaik never called directly by customers): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L96
• IsNewRefCountEnabled (should never need to be called by customers since does nothing but return a constant value): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L166
• MarkDirty (required by binding code afaik, but shouldn't have to be called by customers): https://github.com/xamarin/xamarin-macios/blob/337f3efac4062ad07fd6f9f9c9fd6db40d2454cc/src/Foundation/NSObject2.cs#L177

Ref:

• [Mono.Android] Hide "internal" members of JLO from IDEs. android#4583
• https://xamarinhq.slack.com/archives/C03CCJNR7/p1587407994218100

[spouliot]

Semi random thoughts...

I do not see an issue hiding the properties ([Super]Handle) from intellisense but IMO they should remain visible in the debugger.

The only times I recall seeing NSObject constructors are related to manual binding code for

• adding a NSObject-based pointer to a weak/native managed collection (processed by native code);
• create an instance of an unknown type to get its description

TBH we forgot to make them protected in XAMCORE_2_0 like the generated bindings for the subclasses. So the same solution is that use Runtime.GetNSObject<NSObject> (ptr) if it's really needed (not that we're talking about removing them).

[dalexsoto]

By Hide you mean adding EditorBrowsable with Advanced or Never right? If so 👍 but I have to agree with @spouliot that [Super]Handle should still be visible under the debugger.