build method

  1. @override
Widget build(
  1. BuildContext context,
  2. WidgetRef ref
)
override

Describes the part of the user interface represented by this widget.

The framework calls this method when this widget is inserted into the tree in a given BuildContext and when the dependencies of this widget change (e.g., an InheritedWidget referenced by this widget changes). This method can potentially be called in every frame and should not have any side effects beyond building a widget.

The framework replaces the subtree below this widget with the widget returned by this method, either by updating the existing subtree or by removing the subtree and inflating a new subtree, depending on whether the widget returned by this method can update the root of the existing subtree, as determined by calling Widget.canUpdate.

Typically implementations return a newly created constellation of widgets that are configured with information from this widget's constructor and from the given BuildContext.

The given BuildContext contains information about the location in the tree at which this widget is being built. For example, the context provides the set of inherited widgets for this location in the tree. A given widget might be built with multiple different BuildContext arguments over time if the widget is moved around the tree or if the widget is inserted into the tree in multiple places at once.

The implementation of this method must only depend on:

If a widget's build method is to depend on anything else, use a StatefulWidget instead.

See also:

  • StatelessWidget, which contains the discussion on performance considerations.

Implementation

@override
Widget build(BuildContext context, WidgetRef ref) {
  final train = ref.watch(partitionTrainProvider);
  final tune = ref.watch(partitionTuneProvider);
  final test = ref.watch(partitionTestProvider);
  final useValidation = ref.watch(useValidationSettingProvider);
  final total = train + tune + test;

  return Column(
    crossAxisAlignment: CrossAxisAlignment.start,
    children: [
      Row(
        spacing: configRowSpace,
        children: [
          SettingNumberField(
            label: 'Training %:',
            value: train,
            onChanged: (value) async {
              if (value >= 0 && value <= 100) {
                onTrainChanged(value);
              } else {
                showOutOfRangeWarning();
              }
            },
            tooltip: '''

            The percentage of data allocated for training the model. Ensure
            the total across training, ${useValidation ? "validation" : "tuning"}, and testing sums to 100%.

            ''',
          ),
          SettingNumberField(
            label: '${useValidation ? "Validation" : "Tuning"} %:',
            value: tune,
            onChanged: (value) async {
              if (value >= 0 && value <= 100) {
                onTuneChanged(value);
              } else {
                showOutOfRangeWarning();
              }
            },
            tooltip: '''

            The percentage of data allocated for ${useValidation ? "validating" : "tuning"} the model. Ensure the total across
            training, ${useValidation ? "validation" : "tuning"}, and testing sums to 100%.

            ''',
          ),
          SettingNumberField(
            label: 'Testing %:',
            value: test,
            onChanged: (value) async {
              if (value >= 0 && value <= 100) {
                onTestChanged(value);
              } else {
                showOutOfRangeWarning();
              }
            },
            tooltip: '''

            The percentage of data allocated for testing the model. Ensure the total
            across training, ${useValidation ? "validation" : "tuning"}, and testing sums to 100%.

            ''',
          ),
          Text(
            'Total: $total%',
            style: TextStyle(
              fontSize: 16,
              color: total == 100 ? Colors.green : Colors.red,
              fontWeight: FontWeight.bold,
            ),
          ),
          Container(
            child: MarkdownTooltip(
              message: '''

              Some data scientists think of the second dataset of the
              partitions as a dataset to use for **tuning** the model. Others
              see it as a dataset for **validating** parameter settings. You
              can choose your preference for the nomenclature here. The choice
              does not have any material impact on any analysis.

              ''',
              child: Row(
                children: [
                  const Text(
                    'Use Tuning',
                    style: TextStyle(fontSize: 16),
                  ),
                  Switch(
                    value: useValidation,
                    onChanged: (value) {
                      onValidationChanged(value);
                    },
                  ),
                  const Text(
                    'or Validation',
                    style: TextStyle(fontSize: 16),
                  ),
                ],
              ),
            ),
          ),
        ],
      ),
    ],
  );
}