Skelenot

skeleton.dart

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import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';


class StampWidget extends StatelessWidget {
  const StampWidget._({
    Key? key,
    this.number,
    this.title,
    this.transactions,
  }) : super(key: key);

  factory StampWidget.skeleton() => const StampWidget._(
        number: SkeletonStub(),
        title: SkeletonStub(),
        transactions: SkeletonStub(),
      );

//...

  final Widget? number;
  final Widget? title;
  final Widget? transactions;

  @override
  Widget build(BuildContext context) => StampLayout(
        number: number,
        title: title,
        transactions: transactions,
      );
}

class StampLayout extends StatelessWidget {
  const StampLayout({
    Key? key,
    this.number,
    this.title,
    this.transactions,
  }) : super(key: key);

  final Widget? number;
  final Widget? title;
  final Widget? transactions;

  @override
  Widget build(BuildContext context) => Container(
        padding: const EdgeInsets.all(16),
        decoration: BoxDecoration(
          border: Border.all(
            color: AppTheme.of(context).stampColors.border,
            width: 3,
          ),
          borderRadius: AppTheme.of(context).borderRadius.borderRadius,
        ),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            if (number != null)
              DefaultTextStyle(
                style: AppTheme.of(context).textTheme.caption?.copyWith(
                          color: AppTheme.of(context).stampColors.text,
                        ) ??
                    const TextStyle(),
                child: MinimalBox(
                  height: 16,
                  width: 124,
                  child: number,
                ),
              ),
            if (title != null)
              DefaultTextStyle(
                style: AppTheme.of(context).textTheme.headline1?.copyWith(
                          color: AppTheme.of(context).stampColors.text,
                        ) ??
                    const TextStyle(),
                child: MinimalBox(
                  height: 32,
                  width: 218,
                  child: title,
                ),
              ),
            if (transactions != null)
              DefaultTextStyle(
                style: AppTheme.of(context).textTheme.subtitle1?.copyWith(
                          color: AppTheme.of(context).stampColors.text,
                        ) ??
                    const TextStyle(),
                child: MinimalBox(
                  height: 24,
                  width: double.infinity,
                  child: transactions,
                ),
              ),
          ]
              .addDivider(
                const SizedBox(
                  height: 4,
                  width: double.infinity,
                ),
              )
              .toList(),
        ),
      );
}

class MinimalBox extends StatelessWidget {
  const MinimalBox({
    Key? key,
    this.width,
    this.height,
    this.child,
  }) : super(key: key);

  final Widget? child;
  final double? height;
  final double? width;

  @override
  Widget build(BuildContext context) => ConstrainedBox(
        constraints: BoxConstraints(
          minHeight: height ?? 0,
          minWidth: width ?? 0,
        ),
        child: child,
      );
}

class SkeletonStub extends StatelessWidget {
  const SkeletonStub({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) => SizedBox.shrink(
        child: DecoratedBox(
          decoration: BoxDecoration(
            color: AppTheme.of(context).skeletonColors.background,
            borderRadius: AppTheme.of(context).borderRadius.borderRadius,
          ),
        ),
      );
}