By default it is set to a list consisting of one element, 'OK'. You may use any text, e.g. 'OK', 'Cancel', 'Yes', 'Retry', etc. C is the ratio of width to height. C sets the justification for the C - may be 'center', 'left' or 'right'. Defaults to 'center'.
C sets the keyboard bindings to include , defaults to true.
C sets the keyboard bindings to include , defaults to true. C sets the keyboard bindings to include , defaults to true. C sets the left and right padding around the button, defaults to 0. C sets the above and below padding around the button, defaults to 0. C sets the button foreground colour, defaults to black.