dart:html

setFillColorRgb method

void setFillColorRgb(int r, int g, int b, [ num a = 1 ])

Sets the color used inside shapes. r, g, b are 0-255, a is 0-1.

Source

void setFillColorRgb(int r, int g, int b, [num a = 1]) {
  this.fillStyle = 'rgba($r, $g, $b, $a)';
}