set texture from the class

i made a class that is componenet of GUI like this:

class NavigationControl extends Object{ ... //here i declare Texture2D variable that i want to use var texture : Texture2D;

      ...
      //later in some of the functions i use that texture in GUI element
      GUI.Button(Rect(10,10,100,20),texture);

in the class script i made, after i scroll down, there is a place to put the texture form the inspector. however it never shows up in the game, currently, in the script from where i am using object of this class i make another variable Texture2D, drop there texture, write new function in the class that is used to set the texture from other script, then it shows. other script is attached to camera, maybe that is the problem.