ButtonBarThemeData constructor Null safety

const ButtonBarThemeData(
  1. {MainAxisAlignment? alignment,
  2. MainAxisSize? mainAxisSize,
  3. ButtonTextTheme? buttonTextTheme,
  4. double? buttonMinWidth,
  5. double? buttonHeight,
  6. EdgeInsetsGeometry? buttonPadding,
  7. bool? buttonAlignedDropdown,
  8. ButtonBarLayoutBehavior? layoutBehavior,
  9. VerticalDirection? overflowDirection}
)

Constructs the set of properties used to configure ButtonBar widgets.

Both buttonMinWidth and buttonHeight must be non-negative if they are not null.

Implementation

const ButtonBarThemeData({
  this.alignment,
  this.mainAxisSize,
  this.buttonTextTheme,
  this.buttonMinWidth,
  this.buttonHeight,
  this.buttonPadding,
  this.buttonAlignedDropdown,
  this.layoutBehavior,
  this.overflowDirection,
}) : assert(buttonMinWidth == null || buttonMinWidth >= 0.0),
     assert(buttonHeight == null || buttonHeight >= 0.0);