Android Question Getting property through reflection?

[Troberg]

I want to get a property of an object of (semi)unknown type. By that, I meant that I don't know exactly what type the object is, but I know that it has the property.

I've tried this, but it fails (java.lang.RuntimeException: java.lang.NoSuchFieldException: MenuPresence):

Sub GetProperty(obj As Object, Property As String) As Object
  Dim r As Reflector
  r.Target = obj
  Return r.GetPublicField(Property)
End Sub

Of course, I can do it like this:

Sub GetProperty(obj AsObject, Property AsString) AsObject
  ReturnCallSub(obj, "get" & Property)
End Sub

However, that assumes that all properties have getters and setters, and are not simply public variables of the class.

What am I doing wrong here???

 

[Erel]

The actual field name is _<lower cased field name>.

Unless the code is obfuscated. In that case the field name is random.

 

[LucaMs]

Of course, I can do it like this:

Sub GetProperty(obj AsObject, Property AsString) AsObject
  ReturnCallSub(obj, "get" & Property)
End Sub

Off topic, I know, sorry.

Is ReturnCallSub a new b4a keyword/function?

Thanks

 

[DonManfred]

I dont think so. Probably a sub From troberg...

 

[Troberg]

The actual field name is _<lower cased field name>.

Thanks, that would have taken me a lot of time to figure out.

Is ReturnCallSub a new b4a keyword/function?

Nope, much simpler than that. Sometimes when I copy-paste from the IDE to the web browser, some spaces are lost (for example, every space after "As"). Don't know why, but it happens.

 

[Troberg]

Still don't work. I've given up on that approach now, and use CallSub on the getters and setters.