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网站做竞价,淘宝网站的建设目标是,wordpress 音频,seo推广代运营一.折线图入门效果图代码逻辑1.坐标范围2.网格线3.坐标文字4.边框5.折线数据6.交互行为#xff08;点击折线区域#xff09;代码实例import package:flutter/cupertino.dart; import package:flutter/material.dart;import package:fl_chart/fl_chart.dart; //导入包class Ho…一.折线图入门效果图代码逻辑1.坐标范围2.网格线3.坐标文字4.边框5.折线数据6.交互行为点击折线区域代码实例import package:flutter/cupertino.dart; import package:flutter/material.dart; import package:fl_chart/fl_chart.dart; //导入包 class HomePage extends StatefulWidget { const HomePage({super.key}); override StateStatefulWidget createState() _HomePageState(); } class _HomePageState extends StateHomePage { //构建UI override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(title: const Text(折线图入门示例)), body: Padding( padding: const EdgeInsets.all(16.0), child: LineChart( //f1_chart提供的主控件,用于显示折线图 mainData(), ), ), ); } // 折线图配置 LineChartData mainData() { return LineChartData( //1.坐标范围 minX: 0, maxX: 6, minY: 0, maxY: 6, //2.网格线 gridData: FlGridData( //默认情况下内部线是虚线,外部线是实线 show: true,//启动网格 horizontalInterval: 1, //每隔一个单元绘制一条水平线 verticalInterval: 1, //每隔一个单元绘制一条垂直线 // getDrawingHorizontalLine: (value) { //内部横实线 // return FlLine( // color: Colors.grey, // strokeWidth: 1, // dashArray: null, // 设为0或null代表实线 // ); // }, // // getDrawingVerticalLine: (value) { //内部竖实线 // return FlLine( // color: Colors.grey.withOpacity(0.5), // strokeWidth: 1, // dashArray: null, // ← 实线 // ); // }, ), //3.坐标文字 titlesData: FlTitlesData( bottomTitles: //横轴 AxisTitles( sideTitles: SideTitles( showTitles: true, //打开X轴标签显示 interval: 1,//每隔1单位画一个刻度并显示数字 getTitlesWidget: (value, meta) { //显示每个X值对应显示什么文字(会覆盖默认的显示数字) const style TextStyle(fontSize: 12); switch (value.toInt()) { case 0: return const Text(一, style: style); case 1: return const Text(二, style: style); case 2: return const Text(三, style: style); case 3: return const Text(四, style: style); case 4: return const Text(五, style: style); case 5: return const Text(六, style: style); case 6: return const Text(日, style: style); } return const Text(); }, ), ), leftTitles: //纵轴 AxisTitles( sideTitles: SideTitles( showTitles: true, //打开Y轴标签显示 interval: 1,//每隔1单位画一个刻度并显示数字(默认显示Y轴数字) ), ), rightTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)),//右侧轴 topTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)), //顶部轴 ), //4.边框 borderData: FlBorderData( show: true, //显示边框 border: Border.all(color: Colors.red), ), //5.折线数据 lineBarsData: [ LineChartBarData( isCurved: true, // 是否平滑曲线 color: Colors.blue, //折线颜色 barWidth: 3, dotData: FlDotData(show: true), // 显示折线点 belowBarData: BarAreaData( //曲线下方区域 show: true, color: Colors.blue.withOpacity(0.2), // 曲线下方阴影颜色 ), spots: const [ //折线的点的数据 FlSpot(0, 1), FlSpot(1, 3), FlSpot(2, 5), FlSpot(3, 4.5), FlSpot(4, 3.5), FlSpot(5, 5), FlSpot(6, 4), ], ), ], //6.用来控制折线图的触摸和交互行为 lineTouchData: LineTouchData( touchTooltipData: LineTouchTooltipData( tooltipBgColor: Colors.blueAccent.withOpacity(0.8), ), handleBuiltInTouches: true, // 启用点击浮窗 ), ); } }二.交互式折线图效果图代码逻辑1.定义输入框控制器和焦点控制器2.初始化存储数据点的列表3.定义取消焦点的方法4.定义添加数据点的方法5.定义删除数据点的方法6.定义清除所有数据点的方法7.销毁的相关操作8.具体UI输入行添加按钮清空按钮折线图区域当前坐标点列表9.折线图的具体配置代码实例import package:flutter/material.dart; import package:fl_chart/fl_chart.dart; class HomePage extends StatefulWidget { const HomePage({super.key}); override StateStatefulWidget createState() _HomePageState(); } class _HomePageState extends StateHomePage { final TextEditingController _xController TextEditingController(); //输入框控制器 final TextEditingController _yController TextEditingController(); //输入框控制器 final FocusNode _xFocusNode FocusNode(); final FocusNode _yFocusNode FocusNode(); ListFlSpot userSpots [ //存储用户输入的数据点 const FlSpot(0, 1), //初始的数据点 const FlSpot(1, 2), const FlSpot(2, 3), ]; //取消焦点方法 void _unfocusAll() { _xFocusNode.unfocus(); // 取消X输入框焦点 _yFocusNode.unfocus(); // 取消Y输入框焦点 } //添加数据点的方法 void _addPoint() { double? x double.tryParse(_xController.text); double? y double.tryParse(_yController.text); if (x ! null y ! null x 10 y 10 ) { setState(() { userSpots.add(FlSpot(x, y));//添加新点 userSpots.sort((a, b) a.x.compareTo(b.x));//按X坐标排序 }); //恢复数据框 _xController.clear(); _yController.clear(); _unfocusAll();//取消焦点 } else { //输入无效时显示提示 ScaffoldMessenger.of(context).showSnackBar( const SnackBar(content: Text(请输入小于或等于10的有效数字)), ); _unfocusAll(); // 错误时也取消焦点 } } //删除数据点的方法 void _removePoint(int index) { setState(() { userSpots.removeAt(index); //删除指定索引的点 }); } //清除所有数据点的方法 void _clearAll() { setState(() { userSpots.clear();//清空所有点 _unfocusAll(); // 清空时也取消焦点 }); } override void dispose() { _xController.dispose(); _yController.dispose(); _xFocusNode.dispose(); _yFocusNode.dispose(); super.dispose(); } override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(title: const Text(交互式折线图)), body: Padding( padding: const EdgeInsets.all(10), child: Column( children: [ // 1.输入行 Row( children: [ //X坐标输入框 Expanded( child: TextField( controller: _xController, focusNode: _xFocusNode, // 绑定FocusNode keyboardType: TextInputType.number, //数字键盘 decoration: const InputDecoration( labelText: X 坐标, border: OutlineInputBorder(), ), ), ), const SizedBox(width: 10), //Y坐标输入框 Expanded( child: TextField( controller: _yController, focusNode: _yFocusNode, // 绑定FocusNode keyboardType: TextInputType.number, decoration: const InputDecoration( labelText: Y 坐标, border: OutlineInputBorder(), ), ), ), const SizedBox(width: 10), //添加按钮 ElevatedButton( onPressed: _addPoint, //添加的点击事件 child: const Text(添加), ), ], ), const SizedBox(height: 15), //2.清空按钮 Row( mainAxisAlignment: MainAxisAlignment.end, children: [ TextButton.icon( onPressed: userSpots.isEmpty ? null : _clearAll, //点击事件 icon: const Icon(Icons.delete_forever, color: Colors.red), label: const Text( 清空所有, style: TextStyle(color: Colors.red), ), ), ], ), const SizedBox(height: 10), // 3.折线图区域 Expanded( flex: 2, child: LineChart(mainData()), ), const SizedBox(height: 20), //4.当前坐标点列表 Expanded( flex: 1, child: userSpots.isEmpty ? const Center(child: Text(暂无数据点)) : ListView.builder( itemCount: userSpots.length, itemBuilder: (context, index) { final spot userSpots[index]; return Card( child: ListTile( leading: const Icon(Icons.circle, color: Colors.blue), title: Text(X: ${spot.x}, Y: ${spot.y}), trailing: IconButton( icon: const Icon(Icons.delete, color: Colors.red), onPressed: () _removePoint(index), ), ), ); }, ), ), ], ), ), ); } //折线图配置 LineChartData mainData() { return LineChartData( //1范围 minX: 0, maxX: 10, //x轴范围 minY: 0, maxY: 10, //Y轴范围 //2.网格线 gridData: FlGridData(show: true), //3.坐标轴标签 titlesData: FlTitlesData( bottomTitles: AxisTitles( sideTitles: SideTitles( showTitles: true, interval: 1, reservedSize: 30, //为标签保留空间 ), ), leftTitles: AxisTitles( sideTitles: SideTitles( showTitles: true, interval: 1, //标签间隔 reservedSize: 30, //为标签保留空间 ), ), rightTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)), topTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)), ), //4.边框 borderData: FlBorderData( show: true, border: Border.all(color: Colors.black26), ), //5.折线数据 lineBarsData: [ LineChartBarData( isCurved: true, //曲线连接 color: Colors.blue, //线条颜色 barWidth: 3, //线条宽度 dotData: FlDotData(show: true),//显示数据点 belowBarData: BarAreaData(show: true, color: Colors.blue.withOpacity(0.2)), //区域填充 spots: userSpots.isNotEmpty ? userSpots : [const FlSpot(0, 0)], // 防止空图报错 ), ], //6.交互行为 lineTouchData: LineTouchData( touchTooltipData: LineTouchTooltipData( tooltipBgColor: Colors.blueAccent.withOpacity(0.8), ), handleBuiltInTouches: true, ), ); } }