filled property
final
If true the decoration's container is filled with fillColor.
Typically this field set to true if border is const UnderlineInputBorder().
The decoration's container is the area which is filled if isFilled is
true and bordered per the border. It's the area adjacent to
decoration.icon and above the widgets that contain helperText,
errorText, and counterText.
This property is false by default.
Implementation
final bool filled