padding property
The padding between the button's boundary and its child.
The vertical aspect of the default or user-specified padding is adjusted automatically based on visualDensity.
When the visual density is VisualDensity.compact, the top and bottom insets are reduced by 8 pixels or set to 0 pixels if the result of the reduced padding is negative. For example: the visual density defaults to VisualDensity.compact on desktop and web, so if the provided padding is 16 pixels on the top and bottom, it will be reduced to 8 pixels on the top and bottom. If the provided padding is 4 pixels, the result will be no padding on the top and bottom.
When the visual density is VisualDensity.comfortable, the top and bottom insets are reduced by 4 pixels or set to 0 pixels if the result of the reduced padding is negative.
When the visual density is VisualDensity.standard the top and bottom insets are not changed. The visual density defaults to VisualDensity.standard on mobile.
See ThemeData.visualDensity for more details.
Implementation
final MaterialStateProperty<EdgeInsetsGeometry?>? padding;