Material constructor

const Material({Key key, MaterialType type: MaterialType.canvas, double elevation: 0.0, Color color, Color shadowColor: const Color(0xFF000000), TextStyle textStyle, BorderRadius borderRadius, ShapeBorder shape, Clip clipBehavior: Clip.none, Duration animationDuration: kThemeChangeDuration, Widget child })

Creates a piece of material.

The type, elevation, shadowColor, and animationDuration arguments must not be null.

If a shape is specified, then the borderRadius property must be null and the type property must not be MaterialType.circle. If the borderRadius is specified, then the type property must not be MaterialType.circle. In both cases, these restrictions are intended to catch likely errors.

Implementation 

const Material({
  Key key,
  this.type = MaterialType.canvas,
  this.elevation = 0.0,
  this.color,
  this.shadowColor = const Color(0xFF000000),
  this.textStyle,
  this.borderRadius,
  this.shape,
  this.clipBehavior = Clip.none,
  this.animationDuration = kThemeChangeDuration,
  this.child,
}) : assert(type != null),
     assert(elevation != null),
     assert(shadowColor != null),
     assert(!(shape != null && borderRadius != null)),
     assert(animationDuration != null),
     assert(!(identical(type, MaterialType.circle) && (borderRadius != null || shape != null))),
     assert(clipBehavior != null),
     super(key: key);