debugDescribeChildren method Null safety
override
Returns a list of DiagnosticsNode
objects describing this node's
children.
Children that are offstage should be added with style
set to
DiagnosticsTreeStyle.offstage to indicate that they are offstage.
The list must not contain any null entries. If there are explicit null
children to report, consider DiagnosticsNode.message or
DiagnosticsProperty<Object> as possible DiagnosticsNode
objects to
provide.
Used by toStringDeep, toDiagnosticsNode and toStringShallow.
See also:
- RenderTable.debugDescribeChildren, which provides high quality custom descriptions for its child nodes.
Implementation
@override
List<DiagnosticsNode> debugDescribeChildren() {
if (_children.isEmpty) {
return <DiagnosticsNode>[DiagnosticsNode.message('table is empty')];
}
final List<DiagnosticsNode> children = <DiagnosticsNode>[];
for (int y = 0; y < rows; y += 1) {
for (int x = 0; x < columns; x += 1) {
final int xy = x + y * columns;
final RenderBox? child = _children[xy];
final String name = 'child ($x, $y)';
if (child != null) {
children.add(child.toDiagnosticsNode(name: name));
} else {
children.add(DiagnosticsProperty<Object>(name, null, ifNull: 'is null', showSeparator: false));
}
}
}
return children;
}