Im trying to add LayoutBuilder into Flet.

[Wanna-Pizza]

Question

First of all, im trying to understand how to create new attribute in Dart? And then use it in python.

I did LayoutBuilder with stack (just for test, and then I will try to remove stack)

I create attribute "layoutWidth" and "layoutHeight", but how to update these values with dart??

Coz when I trying to get values - it prints "None".

Code sample

# DART CONTROL

import 'package:flutter/widgets.dart';

import '../models/control.dart';
import '../utils/alignment.dart';
import '../utils/others.dart';
import 'create_control.dart';







class LayoutBuilderControl extends StatelessWidget {
  final Control? parent;
  final Control control;
  final bool parentDisabled;
  final bool? parentAdaptive;
  final List<Control> children;

  const LayoutBuilderControl({
    super.key,
    this.parent,
    required this.control,
    required this.children,
    required this.parentDisabled,
    required this.parentAdaptive,
  });

  @override
  Widget build(BuildContext context) {
    debugPrint("Stack with layout builder build: ${control.id}");
    bool disabled = control.isDisabled || parentDisabled;
    bool? adaptive = control.attrBool("adaptive") ?? parentAdaptive;




    var clipBehavior =
        parseClip(control.attrString("clipBehavior"), Clip.hardEdge)!;

    StackFit fit = parseStackFit(control.attrString("fit"), StackFit.loose)!;
    
    return constrainedControl(
      context,
      LayoutBuilder(
        builder: (BuildContext context, BoxConstraints constraints) {
          double containerWidth = constraints.maxWidth;
          double containerHeight = constraints.maxHeight;

          var layoutWidth = control.attrDouble("layoutWidth") ?? containerWidth;
          var layoutHeight = control.attrDouble("layoutWeight") ?? containerHeight;

          debugPrint("Stack dimensions: Width: $layoutWidth, Height: $layoutHeight");
          
          var ctrls = children
              .where((c) => c.isVisible)
              .map((c) =>
                  createControl(control, c.id, disabled, parentAdaptive: adaptive))
              .toList();

          return Stack(
            clipBehavior: clipBehavior,
            fit: fit,
            alignment: parseAlignment(control, "alignment") ?? AlignmentDirectional.topStart,
            children: ctrls,
          );
        },
      ),
      parent,
      control,
    );
  }
}



# PYTHON SIDE

@property
 def layout_size(self) -> Optional[str]:
    width = self._get_attr("layoutWidth")
    height = self._get_attr("layoutHeight")
    print(height,width)

Error message

No response

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• I have searched for answers to my question both in the issues and in previous discussions.

[ndonkoHenri]

Discussion on discord: https://discord.com/channels/981374556059086931/1301108300397416548