# withOpacity method

Color withOpacity (double opacity)

Returns a new color that matches this color with the alpha channel replaced with the given `opacity` (which ranges from 0.0 to 1.0).

Out of range values will have unexpected effects.

## Implementation

    Color withOpacity(double opacity) {
      assert(opacity >= 0.0 && opacity <= 1.0);
      return withAlpha((255.0 * opacity).round());
    }