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 d="M22 12C22 17.5228 17.5228 22 12 22C10.1786 22 8.47087 21.513 7 20.6622L2 21.5L2.83209 16C2.29689 14.7751 2 13.4222 2 12C2 6.47715 6.47715 2 12 2C17.5228 2 22 6.47715 22 12Z" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round"/>
<path d="M12.9604 13.8683L15.0399 13.4624L17 14.2149V16.0385C17 16.6449 16.4783 17.1073 15.8901 16.9783C14.3671 16.6444 11.5997 15.8043 9.67826 13.8683C7.84859 12.0248 7.22267 9.45734 7.01039 8.04128C6.92535 7.47406 7.3737 7 7.94306 7H9.83707L10.572 8.96888L10.1832 11.0701" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round"/>
</svg>
''',
  colorFilter: color != null
      ? widgets.ColorFilter.mode(color!, widgets.BlendMode.srcIn)
      : null,
  width: width,
  height: height,
);