build method
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:
- the fields of the widget, which themselves must not change over time, and
- any ambient state obtained from the
context
using BuildContext.dependOnInheritedWidgetOfExactType.
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="M9.8525 14.6334L3.65151 10.6873C2.41651 9.90141 2.41651 8.09858 3.65151 7.31268L9.8525 3.36659C11.1628 2.53279 12.8372 2.53279 14.1475 3.36659L20.3485 7.31268C21.5835 8.09859 21.5835 9.90142 20.3485 10.6873L14.1475 14.6334C12.8372 15.4672 11.1628 15.4672 9.8525 14.6334Z" stroke="currentColor"/>
<path d="M18.2857 12L20.3485 13.3127C21.5835 14.0986 21.5835 15.9014 20.3485 16.6873L14.1475 20.6334C12.8372 21.4672 11.1628 21.4672 9.8525 20.6334L3.65151 16.6873C2.41651 15.9014 2.41651 14.0986 3.65151 13.3127L5.71429 12" stroke="currentColor"/>
</svg>
''',
colorFilter:
color != null ? widgets.ColorFilter.mode(color!, widgets.BlendMode.srcIn) : null,
width: width,
height: height,
);