build method

  1. @override
Widget build(
  1. BuildContext context
)
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
widgets.Widget build(widgets.BuildContext context) => SvgPicture.string(
      '''
<svg width="24" height="24" viewBox="0 0 24 24" stroke-width="1.5" fill="none" xmlns="http://www.w3.org/2000/svg">
<path fill-rule="evenodd" clip-rule="evenodd" d="M19.9463 1.59905C19.7411 1.27486 19.3244 1.15775 18.9804 1.32762C18.346 1.64091 17.3056 2.37972 16.4755 2.99465C16.0485 3.31089 15.6577 3.60914 15.3739 3.82819L15.3143 3.87417C15.128 3.77341 14.8928 3.65452 14.6218 3.53557C13.9471 3.23941 12.9931 2.91677 12 2.91677C11.0069 2.91677 10.0529 3.23941 9.37823 3.53557C9.1077 3.65432 8.87275 3.773 8.68662 3.87366L8.63018 3.82977C8.3491 3.61133 7.9635 3.31397 7.54606 2.99878C6.73113 2.38346 5.73398 1.65332 5.1806 1.34495C4.8381 1.15409 4.40638 1.25926 4.19003 1.58626C2.61279 3.97014 2.55039 5.87414 3.00077 7.23562C3.21973 7.8975 3.54828 8.39461 3.82405 8.72806C3.84973 8.75912 3.875 8.78881 3.89975 8.81715C3.11813 10.4241 2.25 12.7782 2.25 15.3334C2.25 15.7476 2.58579 16.0834 3 16.0834C4.25484 16.0834 5.25805 16.4548 5.94897 16.827C6.29433 17.0131 6.55888 17.1979 6.7337 17.3331C6.77007 17.3612 6.80247 17.3871 6.83081 17.4103L6.83144 17.4126C6.87212 17.5615 6.93347 17.771 7.01789 18.0212C7.18586 18.5189 7.44942 19.19 7.83068 19.8678C8.57056 21.1831 9.89029 22.7501 12 22.7501C14.1097 22.7501 15.4294 21.1831 16.1693 19.8678C16.5506 19.19 16.8141 18.5189 16.9821 18.0212C17.0665 17.771 17.1279 17.5615 17.1686 17.4126L17.1692 17.4103C17.1975 17.3871 17.2299 17.3612 17.2663 17.3331C17.4411 17.1979 17.7057 17.0131 18.051 16.827C18.7419 16.4548 19.7452 16.0834 21 16.0834C21.4142 16.0834 21.75 15.7476 21.75 15.3334C21.75 12.7788 20.8823 10.4252 20.1008 8.81827C20.1254 8.79035 20.1504 8.76112 20.1759 8.73056C20.4529 8.39853 20.7847 7.90372 21.0121 7.24488C21.4796 5.89083 21.458 3.98802 19.9463 1.59905ZM11 17.25C10.5858 17.25 10.25 17.5858 10.25 18C10.25 18.4142 10.5858 18.75 11 18.75H11.25V19C11.25 19.4142 11.5858 19.75 12 19.75C12.4142 19.75 12.75 19.4142 12.75 19V18.75H13C13.4142 18.75 13.75 18.4142 13.75 18C13.75 17.5858 13.4142 17.25 13 17.25H11ZM7.96967 11.9697C8.26256 11.6768 8.73744 11.6768 9.03033 11.9697L10.5303 13.4697C10.8232 13.7626 10.8232 14.2374 10.5303 14.5303C10.2374 14.8232 9.76256 14.8232 9.46967 14.5303L7.96967 13.0303C7.67678 12.7374 7.67678 12.2626 7.96967 11.9697ZM16.0303 13.0303C16.3232 12.7374 16.3232 12.2626 16.0303 11.9697C15.7374 11.6768 15.2626 11.6768 14.9697 11.9697L13.4697 13.4697C13.1768 13.7626 13.1768 14.2374 13.4697 14.5303C13.7626 14.8232 14.2374 14.8232 14.5303 14.5303L16.0303 13.0303Z" fill="currentColor"/>
</svg>
''',
      colorFilter:
          color != null ? widgets.ColorFilter.mode(color!, widgets.BlendMode.srcIn) : null,
      width: width,
      height: height,
    );