Flutter - Remove default padding in Slider

Question

I am wondering how I can remove the default padding in Flutter Slider

Current output is like this, default padding of Slider is clearly visible

Here's my code::

                    Positioned(
                      child: Align(
                        alignment: Alignment.bottomLeft,
                        child: SliderTheme(
                            data: SliderTheme.of(context).copyWith(
                              trackHeight: 2.0,
                              thumbColor: Colors.transparent,
                              thumbShape: RoundSliderThumbShape(enabledThumbRadius: 0.0),
                            ),
                            child: Container(
                                width: 380.0,
                                height: 20.0,
                                padding: EdgeInsets.all(0.0),
                                decoration: BoxDecoration(
                                  border: Border.all(color: Colors.blueAccent)
                                ),
                                child: Slider(
                                  value: 50,
                                  min: 1,
                                  max: 100,
                                  divisions: 100,
                                  activeColor: colors.primaryRed,
                                  inactiveColor: Colors.white,
                                  onChanged: (double newValue) {
                                    print(newValue);
                                  },
                                )
                            )
                        ),
                      ),
                    )

Answer 1

you can fix it with custom trackShape like this:

add this line to SliderTheme data:

SliderTheme(
  data: SliderThemeData(
    // here
    trackShape: CustomTrackShape(),
  ),
  child: Slider(
    ```
  ),
),

then inside CustomTrackShape() you must write this code:

class CustomTrackShape extends RoundedRectSliderTrackShape {
  @override
  Rect getPreferredRect({
    required RenderBox parentBox,
    Offset offset = Offset.zero,
    required SliderThemeData sliderTheme,
    bool isEnabled = false,
    bool isDiscrete = false,
  }) {
    final trackHeight = sliderTheme.trackHeight;
    final trackLeft = offset.dx;
    final trackTop = offset.dy + (parentBox.size.height - trackHeight!) / 2;
    final trackWidth = parentBox.size.width;
    return Rect.fromLTWH(trackLeft, trackTop, trackWidth, trackHeight);
  }
}