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="M3 9.25C2.58579 9.25 2.25 9.58579 2.25 10V19C2.25 20.5188 3.48122 21.75 5 21.75H16C16.1989 21.75 16.3897 21.671 16.5303 21.5303L16.75 21.3107V21.1219C15.9585 21.401 15.0421 21.224 14.409 20.591C13.5303 19.7123 13.5303 18.2877 14.409 17.409L17.409 14.409C18.2877 13.5303 19.7123 13.5303 20.591 14.409L21.75 15.568V10C21.75 9.58579 21.4142 9.25 21 9.25H3Z" fill="currentColor"/>
<path fill-rule="evenodd" clip-rule="evenodd" d="M7 1.25C7.41421 1.25 7.75 1.58579 7.75 2V6C7.75 6.41421 7.41421 6.75 7 6.75C6.58579 6.75 6.25 6.41421 6.25 6V4.75H5C4.30964 4.75 3.75 5.30964 3.75 6V10C3.75 10.4142 3.41421 10.75 3 10.75C2.58579 10.75 2.25 10.4142 2.25 10V6C2.25 4.48122 3.48122 3.25 5 3.25H6.25V2C6.25 1.58579 6.58579 1.25 7 1.25ZM15 1.25C15.4142 1.25 15.75 1.58579 15.75 2V6C15.75 6.41421 15.4142 6.75 15 6.75C14.5858 6.75 14.25 6.41421 14.25 6V4.75H10.5C10.0858 4.75 9.75 4.41421 9.75 4C9.75 3.58579 10.0858 3.25 10.5 3.25H14.25V2C14.25 1.58579 14.5858 1.25 15 1.25ZM17.75 4C17.75 3.58579 18.0858 3.25 18.5 3.25H19C20.5188 3.25 21.75 4.48122 21.75 6V10C21.75 10.4142 21.4142 10.75 21 10.75C20.5858 10.75 20.25 10.4142 20.25 10V6C20.25 5.30964 19.6904 4.75 19 4.75H18.5C18.0858 4.75 17.75 4.41421 17.75 4Z" fill="currentColor"/>
<path fill-rule="evenodd" clip-rule="evenodd" d="M18.4697 15.4697C18.7626 15.1768 19.2374 15.1768 19.5303 15.4697L22.5303 18.4697C22.8232 18.7626 22.8232 19.2374 22.5303 19.5303C22.2374 19.8232 21.7626 19.8232 21.4697 19.5303L19.75 17.8107V22C19.75 22.4142 19.4142 22.75 19 22.75C18.5858 22.75 18.25 22.4142 18.25 22V17.8107L16.5303 19.5303C16.2374 19.8232 15.7626 19.8232 15.4697 19.5303C15.1768 19.2374 15.1768 18.7626 15.4697 18.4697L18.4697 15.4697Z" fill="currentColor"/>
</svg>
''',
      colorFilter:
          color != null ? widgets.ColorFilter.mode(color!, widgets.BlendMode.srcIn) : null,
      width: width,
      height: height,
    );