code: public TwoColors getTexturedButtonInteriorColors(CommonControlState type) {
          switch (type) {
  
          case DISABLED:
              return texturedButtonInteriorDisabled;
  
          case DISABLED_SELECTED:
              return texturedButtonInteriorDisabledSelected;
  
          case ENABLED:
              return texturedButtonInteriorEnabled;
  
          case PRESSED:
              return texturedButtonInteriorPressed;
  
          case DEFAULT:
              return texturedButtonInteriorDefault;
  
          case SELECTED:
              return texturedButtonInteriorSelected;
  
          case DEFAULT_PRESSED:
              return texturedButtonInteriorDefaultPressed;
  
          case PRESSED_SELECTED:
              return texturedButtonInteriorPressedSelected;
          }
  
          return null;
      }
docs: Get the colors for the interior.
  
  @param  type the button type. Derived from the state.
  
  @return a two-tuple of colors for top and bottom gradient.