How to dynamically adjust scroll height with TabBar in Flutter DataTable (SfDataGrid)?

In this article, we will show you how to dynamically adjust scroll height with TabBar in Flutter DataTable.

Initialize the SfDataGrid with the necessary properties and set up the DataGridSource, calculating the initial height using DataGridSource.rows. Add a listener to the ScrollController to update the height of a SizedBox based on the scroll position. Additionally, reset the scroll position when switching tabs. In the build method, use a SingleChildScrollView containing a SizedBox that dynamically adjusts its height. Inside the SizedBox, include a TabBar and TabBarView to display the DataGrid. Use a GestureDetector to handle drag updates and adjust the scroll position accordingly. The DataGridController manages vertical scrolling when the SizedBox collapses, ensuring content remains accessible. This setup enables smooth scrolling and dynamic height adjustment for the DataGrid within the TabBar.

 @override
  void initState() {
    super.initState();
    _controller = ScrollController();
    _dataGridController = DataGridController();
    _tabController = TabController(length: 3, vsync: this);
    employees = getEmployeeData();
    employeeDataSource = EmployeeDataSource(employeeData: employees);
    // Calculate the initial height of the DataGrid based on row count.
    dataGridHeight =
        (employeeDataSource.rows.length * rowHeight) + headerRowHeight;
    // Add listener to handle scroll-based height adjustments.
    _controller.addListener(_updateSizedBoxHeight);

    // Listen to tab changes and reset scroll position.
    _tabController.addListener(() {
      if (_tabController.indexIsChanging) {
        _resetScrollOffset();
      }
    });
  }

  // Resets the scroll position and restores the initial height when switching tabs.
  void _resetScrollOffset() {
    _controller.jumpTo(0);
    _dataGridController.scrollToRow(0);
    setState(() {
      // Restore the initial height.
      currentSizedBoxHeight = initialSizedBoxHeight;
    });
  }

  // Updates the height of a SizedBox dynamically based on scroll position.
  void _updateSizedBoxHeight() {
    double shrinkOffset = _controller.offset;
    double newHeight =
        (initialSizedBoxHeight - shrinkOffset).clamp(0, initialSizedBoxHeight);

    if (newHeight != currentSizedBoxHeight) {
      setState(() {
        currentSizedBoxHeight = newHeight;
      });
    } else {
      // Ensures UI updates when initial scroll.
      setState(() {});
    }
    // If the height is fully collapsed, adjust DataGrid scroll position.
    if (newHeight == 0) {
      _dataGridController
          .scrollToVerticalOffset(_controller.offset - initialSizedBoxHeight);
    }

    // Ensure DataGrid scrolls back to the top when user scrolls back up.
    if (_controller.offset <= 0) {
      _dataGridController.scrollToRow(0);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: LayoutBuilder(builder: (context, constraints) {
        return SingleChildScrollView(
          controller: _controller,
          child: SizedBox(
            height: initialSizedBoxHeight + tabHeight + dataGridHeight,
            child: Transform.translate(
              // Moves content based on scroll position for a smooth effect.
              offset:
                  Offset(0, _controller.hasClients ? _controller.offset : 0),
              child: SizedBox(
                height: constraints.maxHeight,
                child: Column(
                  children: [
                    // Displays a resizable header space before the TabBar.
                    SizedBox(
                      height: currentSizedBoxHeight,
                      child: const Center(
                          child: Text(
                        'Tab Bar',
                        style: TextStyle(fontSize: 40),
                      )),
                    ),
                    SizedBox(
                      height: tabHeight,
                      child: TabBar(
                        controller: _tabController,
                        tabs: const [
                          Tab(text: "Tab 1"),
                          Tab(text: "Tab 2"),
                          Tab(text: "Tab 3"),
                        ],
                      ),
                    ),
                    SizedBox(
                      height: constraints.maxHeight -
                          currentSizedBoxHeight -
                          tabHeight,
                      child: TabBarView(
                        controller: _tabController,
                        children: List.generate(3, (index) {
                          return buildDataGrid();
                        }),
                      ),
                    )
                  ],
                ),
              ),
            ),
          ),
        );
      }),
    );
  }

You can download this example on GitHub.