Container({Key key, FractionalOffset alignment, EdgeInsets padding, Decoration decoration, Decoration foregroundDecoration, double width, double height, BoxConstraints constraints, EdgeInsets margin, Matrix4 transform, Widget child })

Creates a widget that combines common painting, positioning, and sizing widgets.

The height and width values include the padding.

Source 

Container({
  Key key,
  this.alignment,
  this.padding,
  this.decoration,
  this.foregroundDecoration,
  double width,
  double height,
  BoxConstraints constraints,
  this.margin,
  this.transform,
  this.child
}) : constraints =
      (width != null || height != null)
        ? constraints?.tighten(width: width, height: height)
          ?? new BoxConstraints.tightFor(width: width, height: height)
        : constraints,
     super(key: key) {
  assert(margin == null || margin.isNonNegative);
  assert(padding == null || padding.isNonNegative);
  assert(decoration == null || decoration.debugAssertIsValid());
  assert(constraints == null || constraints.debugAssertIsValid());
}