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flutter - Flutter CustomPaint，如何启用平移？

问题描述

我正在使用 FlutterCustomPaint绘制散点图，用户可以通过点击添加点。由于整个图表无法放在移动屏幕上，我希望用户能够平移。我该如何启用它？目前，图表没有平移，所以我只能看到它的一部分。这是我的代码：

import 'dart:io';
import 'dart:ui';
import 'package:flutter/material.dart';

class Draw extends StatefulWidget {

  String eventName;

  Draw({this.eventName});

  @override
  _DrawState createState() => _DrawState();
}

class _DrawState extends State<Draw> {
  List<Offset> points = List();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: GestureDetector(
        child: CustomPaint(
          size: Size.infinite,
          painter: DrawingPainter(),
        ),
      ),
    );
  }
}

class DrawingPainter extends CustomPainter {

  DrawingPainter();

  Paint tickSettings = Paint()
    ..strokeCap = (Platform.isAndroid) ? StrokeCap.butt : StrokeCap.round
    ..isAntiAlias = true
    ..color = Colors.grey
    ..strokeWidth = 5.0;

  static double axisXCoord = 60;
  static double axisHt = 1000;
  var ticks = List<Offset>.generate(10, (i) => Offset(axisXCoord, i * (axisHt / 10) + 30));

  @override
  void paint(Canvas canvas, Size size) {
    canvas.drawPoints(PointMode.points, ticks, tickSettings);
  }

  @override
  bool shouldRepaint(DrawingPainter oldDelegate) => true;
}

（注意，我还看到了 Google 的Flutter Charts库，但我的理解是交互性仅限于一些事情，比如选择图表上的现有点。）

标签： flutterflutter-layout

解决方案

似乎我通过GestureDetector将SingleChildScrollView.

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