Question

在Flutter应用中，我正在尝试实现在以下位置找到的OrdinalComboBarLineChart：https://github.com/google/charts。

它在调试模式下工作。但是，在发布模式下，它将引发错误，并且无法正确显示图表。我收到以下错误：

I/flutter (26577): The following RenderObject was being processed when the exception was fired:
I/flutter (26577):   ChartContainerRenderObject<String>#8d79e NEEDS-PAINT
I/flutter (26577):   parentData: <none>
I/flutter (26577):   constraints: BoxConstraints(w=360.0, h=640.0)
I/flutter (26577):   semantic boundary
I/flutter (26577):   size: Size(0.0, 0.0)
I/flutter (26577): This RenderObject has no descendants.

我已经找到问题所在，这与MaterialApp小部件内的图表有关。就像我删除MaterialApp小部件时一样，它确实可以工作。

下面是产生此错误的代码：

import 'package:flutter/material.dart';
import 'package:charts_flutter/flutter.dart' as charts;

void main() {
  runApp(new OrdinalComboBarLineChart());
}

class OrdinalComboBarLineChart extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    List<charts.Series> seriesList = _createSampleData();

    return MaterialApp(
        home: Container(
            height: 205.0,
            width: 350.0,
            child: charts.OrdinalComboChart(seriesList,
                animate: false,
                defaultRenderer: charts.LineRendererConfig(areaOpacity: 0.8, includeArea: true),
                customSeriesRenderers: [
                  new charts.LineRendererConfig(customRendererId: 'LineOne'),
                ])));
  }

  /// Create series list with multiple series
  List<charts.Series<OrdinalSales, String>> _createSampleData() {
    var categoryOne = [
      new OrdinalSales('0:00', 0),
      new OrdinalSales('12:00', 0),
      new OrdinalSales('23:59', 25),
    ];

    var lineOne = [
      new OrdinalSales('0:00', 30),
      new OrdinalSales('12:00', 15),
      new OrdinalSales('23:59', 7),
    ];

    final Color myRed = const Color(0xFFEB4141);
    final Color myDarkBackground = const Color(0xFF101926);

    return [
      new charts.Series<OrdinalSales, String>(
          id: 'CategoryOne',
          colorFn: (_, __) => charts.Color(
              r: myRed.red, g: myRed.green, b: myRed.blue, a: myRed.alpha),
          domainFn: (OrdinalSales sales, _) => sales.year,
          measureFn: (OrdinalSales sales, _) => sales.sales,
          data: categoryOne),
      new charts.Series<OrdinalSales, String>(
          id: 'LineOne ',
          colorFn: (_, __) => charts.Color(
              r: myDarkBackground.red,
              g: myDarkBackground.green,
              b: myDarkBackground.blue,
              a: myDarkBackground.alpha),
          domainFn: (OrdinalSales sales, _) => sales.year,
          measureFn: (OrdinalSales sales, _) => sales.sales,
          data: lineOne)
        ..setAttribute(charts.rendererIdKey, 'LineOne'),
    ];
  }
}

/// Sample ordinal data type.
class OrdinalSales {
  final String year;
  final int sales;
  OrdinalSales(this.year, this.sales);
}

我正在使用 chart_flutter：^ 0.5.0

MartialApp内的Flutter（Google）OrdinalComboBarLineChart，发布模式下发生错误：NEEDS-PAINT

0 个答案: