sliver static method

GetSliverAppBar sliver({ Widget? leading, Widget? bottom, Widget? flexibleSpace, Widget? sliverRefresh, List<Widget>? actions, List<Widget>? largeActions, LinearProgress? progress, Widget? customTitle, Widget? customLargeTitle, String? title, TextStyle? titleStyle, TextStyle? largeTitleStyle, ShapeBorder? shape, Color? backgroundColor, bool largeTitle = true, bool? centerTitle, bool floating = false, bool pinned = true, bool interactive = true, bool showLeading = true, bool translucent = true, bool elevateAlways = true, bool? showProgress, double? elevation, double? toolbarHeight, double bottomHeight = 0.0, double bottomConstant = 36.0, double largeTitleHeight = 47.0, double? leadingWidth, double? titleSpacing, double topPadding = kStandardPadding, double bottomPadding = kStandardPadding, double leftPadding = kStandardPaddingX, double rightPadding = kStandardPaddingX, double? verticalPadding, double? horizontalPadding, SwipeRefreshCallback? onRefresh, })

Implementation

static GetSliverAppBar sliver({
  Widget? leading,
  Widget? bottom, // CupertinoSearchTextField()
  Widget? flexibleSpace,
  Widget? sliverRefresh,
  List<Widget>? actions,
  List<Widget>? largeActions,
  LinearProgress? progress,
  Widget? customTitle,
  Widget? customLargeTitle,
  String? title,
  TextStyle? titleStyle,
  TextStyle? largeTitleStyle,
  ShapeBorder? shape,
  Color? backgroundColor,
  bool largeTitle = true,
  bool? centerTitle,
  bool floating = false,
  bool pinned = true,
  bool interactive = true,
  bool showLeading = true,
  bool translucent = true,
  bool elevateAlways = true,
  bool? showProgress,
  double? elevation,
  double? toolbarHeight,
  double bottomHeight = 0.0,
  double bottomConstant = 36.0,
  double largeTitleHeight = 47.0,
  double? leadingWidth,
  double? titleSpacing,
  double topPadding = kStandardPadding,
  double bottomPadding = kStandardPadding,
  double leftPadding = kStandardPaddingX,
  double rightPadding = kStandardPaddingX,
  double? verticalPadding,
  double? horizontalPadding,
  SwipeRefreshCallback? onRefresh,
}) {
  final _actions = interactive ? actions : null;
  final _largeActions = interactive ? largeActions : null;
  if (leading == null &&
      bottom == null &&
      sliverRefresh == null &&
      (_actions == null || _actions.isEmpty) &&
      (_largeActions == null || _largeActions.isEmpty) &&
      progress == null &&
      showProgress == null &&
      customTitle == null &&
      (customLargeTitle == null || !largeTitle) &&
      (title == null || title.isEmpty)) {
    return [];
  }
  final _topPadding = verticalPadding ?? topPadding;
  final _bottomPadding = verticalPadding ?? bottomPadding;
  final _leftPadding = horizontalPadding ?? leftPadding;
  final _rightPadding = horizontalPadding ?? rightPadding;

  final _progress = progress ??
      (showProgress != null ? LinearProgress(visible: showProgress) : null);

  final _hasLargeTitle = customLargeTitle != null ||
      (title != null && largeTitle) ||
      _largeActions?.isNotEmpty == true;

  final _largeTitleHeight =
      (_progress?.height ?? 0) + (_hasLargeTitle ? largeTitleHeight : 0);

  final _bottomHeight = (_progress?.height ?? 0) +
      (bottom == null
          ? 0
          : bottomHeight +
              bottomConstant +
              _topPadding.half.half +
              _bottomPadding -
              2);

  double _floatingBottomHeight({double visibility = 1.0}) =>
      _bottomHeight +
      (floating ? (_hasLargeTitle ? largeTitleHeight : 0) * visibility : 0.0);

  TextStyle? _titleTextStyle(BuildContext context, {bool large = false}) {
    final _style = large ? largeTitleStyle : titleStyle;
    final _fontSize = large ? 30.0 : null;
    final _fontWeight = large ? FontWeight.bold : null;
    return context.appBarTheme.titleTextStyle?.copyWith(
      fontSize: _style?.fontSize ?? _fontSize,
      color: _style?.color,
      fontWeight: _style?.fontWeight ?? _fontWeight,
      fontFamily: _style?.fontFamily,
    );
  }

  Widget _buildLargeTitle(BuildContext context, {double visibility = 1.0}) {
    Widget? _largeTitle;
    if (customLargeTitle != null) {
      _largeTitle = customLargeTitle;
    } else if (title != null && largeTitle) {
      final _style = _titleTextStyle(context, large: true);
      final _minFontSize = visibility < 1 ? _style?.fontSize ?? 30.0 : 14.0;
      _largeTitle = AutoSizeText(
        title,
        textAlign: TextAlign.start,
        minFontSize: _minFontSize,
        overflow: TextOverflow.ellipsis,
        maxLines: 1,
        style: _style,
      );
    }
    return Container(
      constraints: BoxConstraints(minHeight: bottomConstant),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: [
          if (_largeTitle != null)
            _largeTitle.flex(flex: 1000000000000000000, expanded: true),
          if (_largeActions?.isNotEmpty == true) 2.spaceX,
          const Spacer(),
          ..._largeActions ?? [],
        ],
      ),
    );
  }

  return [
    SliverLayoutBuilder(builder: (context, constraints) {
      // $debugPrint(constraints);
      final _offset = constraints.scrollOffset;
      final _elevation = floating
          ? context.appBarElevation
          : ((_offset * 1.01) - _largeTitleHeight)
              .clamp(0.0, context.appBarElevation);
      final _blur = ((_offset * 1.01) - _largeTitleHeight).clamp(0.0, 6.0);
      final _opacity = ((_offset - 15) / 15).clamp(0.0, 1.0);
      final _dy = ((_offset * -1.01) + 30).clamp(0.0, 14.0);
      final _visibility = ((25 - _offset) / 25).clamp(0.0, 1.0);
      final _overlapping = _offset >= _largeTitleHeight;
      // $debugPrint(elevation);
      return SliverAppBar(
        leadingWidth: leadingWidth ?? (leading == null ? 40.0 : null),
        titleSpacing: titleSpacing ??
            (showLeading ? kDensePaddingX : kStandardPaddingX),
        automaticallyImplyLeading: false,
        leading: showLeading ? leading?.row() ?? GetButton.back() : null,
        centerTitle:
            context.appBarCenterTitle(centerTitle, actions: _actions),
        backgroundColor: (backgroundColor ?? context.primaryColor)
            .applyIf(translucent && _blur > 0, (it) => it?.translucent),
        title: customTitle ??
            title?.mapIt((it) => !_hasLargeTitle
                ? Text(it)
                : Transform.translate(
                    offset: GetOffset.only(dy: _dy),
                    child: Opacity(
                      opacity: _opacity,
                      child: Text(it),
                    ),
                  )),
        titleTextStyle: _titleTextStyle(context),
        actions: _actions,
        elevation: elevation ?? _elevation,
        toolbarHeight: toolbarHeight ?? context.toolbarHeight,
        shape: shape,
        flexibleSpace: flexibleSpace,
        //Blur(blur: _blur)
        floating: floating,
        pinned: pinned,
        bottom: floating || _overlapping && pinned
            ? PreferredSize(
                preferredSize: Size.fromHeight(
                  _floatingBottomHeight(visibility: _visibility),
                ),
                child: Column(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    if (floating && _hasLargeTitle)
                      SizedBox(
                        height: _largeTitleHeight * _visibility,
                        child: Opacity(
                          opacity: _visibility,
                          child: Padding(
                            padding: EdgeInsets.only(
                              top: 5,
                              left: _leftPadding,
                              right: _rightPadding,
                              bottom: _bottomPadding.half,
                            ),
                            child: _buildLargeTitle(
                              context,
                              visibility: _visibility,
                            ),
                          ),
                        ),
                      ),
                    if (bottom != null)
                      Padding(
                        padding: EdgeInsets.only(
                          top: _topPadding.half.half,
                          bottom: _bottomPadding - 2,
                          left: _leftPadding,
                          right: _rightPadding,
                        ),
                        child: bottom,
                      ),
                    if (_progress != null && (!floating || _overlapping))
                      _progress,
                  ],
                ),
              )
            : null,
      );
    }),
    sliverRefresh ??
        CupertinoSliverSwipeRefresh(
          onRefresh: onRefresh,
          backgroundColor: backgroundColor,
        ),
    SliverLayoutBuilder(builder: (context, constraints) {
      // $debugPrint(constraints);
      final _offset = constraints.scrollOffset == 0
          ? constraints.overlap
          : constraints.scrollOffset;
      final _opacity = ((25 - _offset) / 25).clamp(0.0, 1.0);
      final _dy = _offset.clamp(0.0, 20.0);
      final _overlapping = constraints.overlap >= _largeTitleHeight;
      // $debugPrint(_offset);
      return SliverToBoxAdapter(
        child: Stack(
          alignment: Alignment.bottomCenter,
          children: [
            Material(
              color: backgroundColor ?? context.primaryColor,
              shadowColor: context.appBarShadowColor,
              elevation: elevateAlways
                  ? elevation ?? context.appBarElevation * 0.8
                  : 0,
              child: floating ||
                      !(_hasLargeTitle || !_overlapping && bottom != null)
                  ? Container(
                      color: Colors.transparent,
                      height: context.appBarElevation +
                          (floating ? 0 : _largeTitleHeight),
                    )
                  : Container(
                      padding: EdgeInsets.only(
                        left: _leftPadding,
                        right: _rightPadding,
                        bottom: _bottomPadding.half,
                      ),
                      child: Column(
                        mainAxisSize: MainAxisSize.min,
                        children: [
                          if (_hasLargeTitle)
                            Transform.translate(
                              offset: GetOffset.only(dy: -_dy),
                              child: Opacity(
                                opacity: _opacity,
                                child: Padding(
                                  padding: const EdgeInsets.only(top: 6),
                                  child: _buildLargeTitle(context),
                                ),
                              ),
                            ),
                          if (!_overlapping && bottom != null)
                            Padding(
                              padding: EdgeInsets.only(
                                top: _topPadding.half,
                                bottom: _bottomPadding.half,
                              ),
                              child: bottom,
                            ),
                        ],
                      ),
                    ),
            ),
            if (!_overlapping && _progress != null) _progress,
          ],
        ),
      );
    }),
  ];
}