set Box Background Mode
Set the box background mode (filled, outline, or none).
May be one of BOX_BACKGROUND_NONE, BOX_BACKGROUND_FILLED, or BOX_BACKGROUND_OUTLINE.
Note: This method defines TextInputLayout's internal behavior (for example, it allows the hint to be displayed inline with the stroke in a cutout), but doesn't set all attributes that are set in the styles provided for the box background modes. To achieve the look of an outlined or filled text field, supplement this method with other methods that modify the box, such as setBoxStrokeColor(int) and setBoxBackgroundColor(int).
Parameters
box Background Mode
box's background mode