scroll method

void scroll(double? pixels, { required bool animate, })

moves the scroller by the specified pixels in the specified direction

Implementation

void scroll(double? pixels, {required bool animate})  {

  try {
    // check if pixels is null
    pixels ??= 0;

    // scroll up/left
    if (pixels < 0) {

      // already at the start of the list
      if (controller.offset == 0) return;

      // calculate pixels
      pixels = controller.offset - pixels.abs();
      if (pixels < 0) pixels = 0;

      if (animate) {
        controller.animateTo(pixels,
            duration: const Duration(milliseconds: 300),
            curve: Curves.easeOut);
      }
      else {
        controller.jumpTo(pixels);
      }
      return;
    }

    // scroll down/right
    if (pixels > 0) {

      // already at the end of the list
      if (controller.position.maxScrollExtent == controller.offset) return;

      // calculate pixels
      pixels = controller.offset + pixels;
      if (pixels > controller.position.maxScrollExtent) pixels = controller.position.maxScrollExtent;

      if (animate) {
        controller.animateTo(pixels,
            duration: const Duration(milliseconds: 300),
            curve: Curves.easeOut);
      }
      else {
        controller.jumpTo(pixels);
      }
      return;
    }
  }
  catch (e) {
    Log().exception(e, caller: 'scroller.View');
  }
}