Java实战之管家婆记账系统（16）——条形图展示数据界面及功能实现

本节概要

本节主要讲使用条形图展示数据。

前期准备

由于从本节开始就会用到JavaFX的图表，所以在tools包下创建了ChartTools.java，该类集中了本项目所需要用到创建条形图、折线图及饼图的相关方法，这些方法都是自定义的，不过也可以修改作它用，更多关于JavaFX图表的用法可以参考JavaFX的中文官网。

故ChartTools.java内容如下：

package AccountSystem.tools;

import AccountSystem.bean.Session;
import AccountSystem.bean.User;
import AccountSystem.dao.RecordDao;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.chart.*;

import java.util.Calendar;
import java.util.Date;
import java.util.List;

public class ChartTools {private DateTools dateTools = new DateTools();
/*** 操作结果：设置条形图的数据根据给定的月数** @param month        给定的月数* @param barChart     条形图* @param categoryAxis X轴* @param numberAxis   Y轴*/public void public_setMonthBarChartData(int month,BarChart<?, ?> barChart,CategoryAxis categoryAxis,NumberAxis numberAxis) {// 实例化RecordDao对象RecordDao recordDao = new RecordDao();// 设置条形图水平轴的标签名称categoryAxis.setLabel("日期");// 设置条形图垂直轴的标签名称numberAxis.setLabel("金额");// 表示“收入”类型XYChart.Series monthInputSeries = new XYChart.Series();// 并设置该类型的名称monthInputSeries.setName("收入");// 表示“支出”类型XYChart.Series monthOutputSeries = new XYChart.Series();// 并设置该类型的名称monthOutputSeries.setName("支出");
// 清空集合日期标签中的内容categoryAxis.getCategories().clear();// 循环月数，填充数据for (int i = 0; i < month; i++) {// 得到一个Calendar日历对象Calendar calendar = Calendar.getInstance();// 设置时间calendar.setTime(new Date());calendar.add(calendar.MONDAY, -i);Date monthDate = calendar.getTime();// 将monthDate进行格式化处理获取“yyyy-MM-dd”格式String monthStringDate = dateTools.dateFormat(monthDate, "yyyy-MM-dd");// 拼接SQL语句，获取当前日期的收入总额String monthInputsql = "select SUM(rMoney) from tb_records where rType='收入' and MONTH(rDate)= MONTH('" + monthStringDate + "') and uId=" + Session.getUser().getUserId() + ";";// 拼接SQL语句，获取当前日期的支出总额String monthOutputsql = "select SUM(rMoney) from tb_records where rType='支出' and MONTH(rDate)= MONTH('" + monthStringDate + "') and uId=" + Session.getUser().getUserId() + ";";// 执行收入SQL语句查询得到收入总额float monthInput = recordDao.getResultValueBySql(monthInputsql);// 执行支出SQL语句查询得到支出总额float monthOutput = recordDao.getResultValueBySql(monthOutputsql);// 为水平轴添加时间标签categoryAxis.getCategories().add(monthStringDate);// 填充“收入”类型的数据monthInputSeries.getData().add(new XYChart.Data<>(dateTools.dateFormat(dateTools.stringToDate(monthStringDate, "yyyy-MM-dd"), "yyyy-MM"), monthInput));// 填充“支出”类型的数据monthOutputSeries.getData().add(new XYChart.Data<>(dateTools.dateFormat(dateTools.stringToDate(monthStringDate, "yyyy-MM-dd"), "yyyy-MM"), monthOutput));}
// 清除条形图上的所有数据barChart.getData().clear();// 重新填充条形图上的数据barChart.getData().addAll(monthInputSeries, monthOutputSeries);}
/*** 操作结果：设置条形图的数据根据一年（四季度）** @param barChart     条形图* @param categoryAxis X轴* @param numberAxis   Y轴*/public void public_setSeasonBarChartData(BarChart<?, ?> barChart,CategoryAxis categoryAxis,NumberAxis numberAxis) {// 设置条形图水平轴的标签categoryAxis.setLabel("日期");// 设置条形图垂直轴的标签numberAxis.setLabel("金额");// 设置条形图“收入”类型XYChart.Series seasonInputSeries = new XYChart.Series();// 设置条形图“收入”类型的名称seasonInputSeries.setName("收入");// 设置条形图“支出”类型XYChart.Series seasonOutputSeries = new XYChart.Series();// 设置条形图“支出”类型的名称seasonOutputSeries.setName("支出");
// 清空集合日期标签中的内容categoryAxis.getCategories().clear();// 获取一年四季度的所有开始日期和结束日期List<Date[]> list = dateTools.getYearQuarterList(new Date());// 循环遍历日期for (int i = 0; i < list.size(); i++) {// 将开始日期和结束日期格式化处理并拼接标签String strDate = dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "-" + dateTools.dateFormat(list.get(i)[1], "yyyy" + "-MM-dd");// 为水平轴的每条数据添加标签categoryAxis.getCategories().add(strDate);// 获取一季度的收入总额String seasonInputSql = "select SUM(rMoney) from tb_records where rType='收入' and rDate between '" + dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "' and '" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd") + "' and uId=" + Session.getUser().getUserId();// 获取一季度的支出总额String seasonOutpuSql = "select SUM(rMoney) from tb_records where rType='支出' and rDate between '" + dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "' and '" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd") + "' and uId=" + Session.getUser().getUserId();// 执行一季度的收入总额的SQL语句获取收入总额float seasonInput = new RecordDao().getResultValueBySql(seasonInputSql);// 执行一季度的支出总额的SQL语句获取支出总额float seasonOutput = new RecordDao().getResultValueBySql(seasonOutpuSql);// 将数据填充到“收入”类型的条形图中seasonInputSeries.getData().add(new XYChart.Data<>(strDate, seasonInput));// 将数据填充到“支出”类型的条形图中seasonOutputSeries.getData().add(new XYChart.Data<>(strDate, seasonOutput));}// 清除条形图上的数据barChart.getData().clear();// 重新为条形图填充数据barChart.getData().addAll(seasonInputSeries, seasonOutputSeries);}
/*** 操作结果：设置条形图的数据根据给定的天数** @param day          给定的天数* @param barChart     条形图* @param categoryAxis X轴* @param numberAxis   Y轴*/public void public_setBarChartData(int day, BarChart<?, ?> barChart,CategoryAxis categoryAxis,NumberAxis numberAxis) {// 设置水平轴的标签categoryAxis.setLabel("日期");// 设置垂直轴的标签numberAxis.setLabel("金额");// 实例化XYChart.Series对象添加收入数据XYChart.Series inputSeries = new XYChart.Series();// 设置名称inputSeries.setName("收入");// 实例化XYChart.Series对象添加支出数据XYChart.Series outputSeries = new XYChart.Series();// 设置名称outputSeries.setName("支出");
// 清空集合日期标签中的内容categoryAxis.getCategories().clear();// 循环天数，绘制每一天的条形图for (int i = 0; i < day; i++) {// 获取日历对象Calendar calendar = Calendar.getInstance();calendar.add(Calendar.DATE, -i);Date calendarTime = calendar.getTime();// 将日期格式化String date = dateTools.dateFormat(calendarTime, "yyyy-MM-dd");// 拼接每天的收入SQL语句String dateInputsql = "select SUM(rMoney) from tb_records where rType='收入' and rDate= '" + date + "' and " + " uId=" + Session.getUser().getUserId() + ";";// 拼接每天的支出SQL语句String dateOutputsql = "select SUM(rMoney) from tb_records where rType='支出' and rDate= '" + date + "' and " + " uId=" + Session.getUser().getUserId() + ";";// 执行SQL语句，获取每天的收入总额float dateInput = new RecordDao().getResultValueBySql(dateInputsql);// 执行SQL语句，获取每天的支出总额float dateOutput = new RecordDao().getResultValueBySql(dateOutputsql);// 为水平轴添加每天的日期标签categoryAxis.getCategories().add(date);// 将收入数据添加到收入条形图inputSeries.getData().add(new XYChart.Data<>(date, dateInput));// 将支出数据添加到支出条形图outputSeries.getData().add(new XYChart.Data<>(date, dateOutput));}
// 清空条形图上的数据barChart.getData().clear();// 重新填充条形图上的数据barChart.getData().addAll(inputSeries, outputSeries);}
/*** 操作结果：设置折线图的数据根据给定的天数** @param day       给定的天数* @param lineChart 折线图*/public void public_setDayLineChartData(int day, LineChart<?, ?> lineChart,CategoryAxis categoryAxis,NumberAxis numberAxis) {// 设置水平轴的标签categoryAxis.setLabel("日期");// 设置垂直轴的标签numberAxis.setLabel("金额");
// 实例化XYChart.Series对象添加收入数据XYChart.Series inputSeries = new XYChart.Series();// 设置收入名称inputSeries.setName("收入");// 实例化XYChart.Series对象添加支出数据XYChart.Series outputSeries = new XYChart.Series();// 设置支出名称outputSeries.setName("支出");
// 清空集合日期标签中的内容categoryAxis.getCategories().clear();// 循环天数，填充数据for (int i = 0; i < day; i++) {// 得到日历对象Calendar calendar = Calendar.getInstance();calendar.add(Calendar.DATE, -i);Date calendarTime = calendar.getTime();// 将日期格式化String date = dateTools.dateFormat(calendarTime, "yyyy-MM-dd");// 拼接每天收入总额的SQL语句String dateInputsql = "select SUM(rMoney) from tb_records where rType='收入' and rDate= '" + date + "' and uId=" + Session.getUser().getUserId() + ";";// 拼接每天支出总额的SQL语句String dateOutputsql = "select SUM(rMoney) from tb_records where rType='支出' and rDate= '" + date + "' and uId=" + Session.getUser().getUserId() + ";";// 执行SQL语句获取每天收入总额float dateInput = new RecordDao().getResultValueBySql(dateInputsql);// 执行SQL语句获取每天支出总额Object dateOutput = new RecordDao().getResultValueBySql(dateOutputsql);// 添加收入数据inputSeries.getData().add(new XYChart.Data<>(date, dateInput));// 添加支出数据outputSeries.getData().add(new XYChart.Data<>(date, dateOutput));}
// 清空折线图上的数据lineChart.getData().clear();// 重新为折线图填充数据lineChart.getData().addAll(inputSeries, outputSeries);}
/*** 操作结果：设置折线图的数据根据给定的月数** @param month     给定的月数* @param lineChart 折线图*/public void public_setMonthLineChartData(int month, LineChart lineChart, CategoryAxis categoryAxis,NumberAxis numberAxis) {categoryAxis.setLabel("日期");numberAxis.setLabel("金额");
XYChart.Series monthInputSeries = new XYChart.Series();monthInputSeries.setName("收入");
XYChart.Series monthOutputSeries = new XYChart.Series();monthOutputSeries.setName("支出");
// 清空集合日期标签中的内容categoryAxis.getCategories().clear();for (int i = 0; i < month; i++) {Calendar calendar = Calendar.getInstance();calendar.setTime(new Date());calendar.add(calendar.MONDAY, -i);Date monthDate = calendar.getTime();String monthStringDate = dateTools.dateFormat(monthDate, "yyyy-MM-dd");String monthInputsql = "select SUM(rMoney) from tb_records where rType='收入' and MONTH(rDate)= MONTH('" + monthStringDate + "') and uId=" + Session.getUser().getUserId() + ";";String monthOutputsql = "select SUM(rMoney) from tb_records where rType='支出' and MONTH(rDate)= MONTH('" + monthStringDate + "') and uId=" + Session.getUser().getUserId() + ";";float monthInput = new RecordDao().getResultValueBySql(monthInputsql);float monthOutput = new RecordDao().getResultValueBySql(monthOutputsql);monthInputSeries.getData().add(new XYChart.Data<>(dateTools.dateFormat(monthDate, "yyyy-MM"), monthInput));monthOutputSeries.getData().add(new XYChart.Data<>(dateTools.dateFormat(monthDate, "yyyy-MM"), monthOutput));}
lineChart.getData().clear();lineChart.getData().addAll(monthInputSeries, monthOutputSeries);}
/*** 操作结果：设置折线图的数据根据给定的年（四个季度）** @param lineChart    折线图* @param categoryAxis X轴* @param numberAxis   Y轴*/public void public_setSeasonLineChartData(LineChart lineChart, CategoryAxis categoryAxis,NumberAxis numberAxis) {categoryAxis.setLabel("日期");numberAxis.setLabel("金额");XYChart.Series seasonInputSeries = new XYChart.Series();seasonInputSeries.setName("收入");
XYChart.Series seasonOutputSeries = new XYChart.Series();seasonOutputSeries.setName("支出");
// 清空集合日期标签中的内容categoryAxis.getCategories().clear();List<Date[]> list = dateTools.getYearQuarterList(new Date());for (int i = 0; i < list.size(); i++) {String strDate = dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "-" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd");categoryAxis.getCategories().add(strDate);String seasonInputSql = "select SUM(rMoney) from tb_records where rType='收入' and rDate between '" + dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "' and '" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd") + "' and uId=" + Session.getUser().getUserId();String seasonOutputSql = "select SUM(rMoney) from tb_records where rType='支出' and rDate between '" + dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "' and '" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd") + "' and uId=" + Session.getUser().getUserId();float seasonInput = new RecordDao().getResultValueBySql(seasonInputSql);float seasonOutput = new RecordDao().getResultValueBySql(seasonOutputSql);seasonInputSeries.getData().add(new XYChart.Data<>(strDate, seasonInput));seasonOutputSeries.getData().add(new XYChart.Data<>(strDate, seasonOutput));}lineChart.getData().clear();lineChart.getData().addAll(seasonInputSeries, seasonOutputSeries);}
/*** 操作结果：设置饼图的数据根据起始日期和终止日期** @param user      用户对象* @param pieChart  饼图* @param startDate 起止日期* @param endDate   终止日期*/public void public_setDayPieChartData(User user, PieChart pieChart, Date startDate, Date endDate) {// 将开始日期格式化处理String thisStartDate = dateTools.dateFormat(startDate, "yyyy-MM-dd");// 将结束日期格式化处理String thisEndDate = dateTools.dateFormat(endDate, "yyyy-MM-dd");// 拼接收入总额SQL语句String thisInputsql = "select SUM(rMoney) from tb_records where rType='收入' and rDate between '" + thisStartDate + "'" + " " + "and " + "'" + thisEndDate + "' and uId=" + user.getUserId() + ";";// 拼接支出总额SQL语句String thisOutputsql = "select SUM(rMoney) from tb_records where rType='支出' and rDate between '" + thisStartDate + "'" + " " + "and " + "'" + thisEndDate + "' and uId=" + user.getUserId() + ";";// 执行SQL语句获取收入总额float thisInput = new RecordDao().getResultValueBySql(thisInputsql);// 执行SQL语句获取支出总额float thisOutput = new RecordDao().getResultValueBySql(thisOutputsql);// 填充数据到ObservableList集合中ObservableList observableList = FXCollections.observableArrayList(new PieChart.Data("收入", thisInput),new PieChart.Data("支出", thisOutput));
// 顺时针设置饼图的切片pieChart.setClockwise(true);// 方法设置标签行的长度pieChart.setLabelLineLength(50);// 将饼图的标签设置为可见pieChart.setLabelsVisible(true);// 设置饼图的起始角度pieChart.setStartAngle(180);
// 清空饼图的数据pieChart.getData().clear();// 填充数据集合到饼图中pieChart.setData(observableList);}
/*** 操作结果：设置饼图的数据根据给定的天数** @param user     用户对象* @param day      给定的天数* @param pieChart 饼图* @param type     账目类型，收入或支出*/public void public_setWeekPieChartData(User user, int day, PieChart pieChart, String type) {// 实例化RecordDao对象RecordDao recordDao = new RecordDao();// 创建ObservableList集合ObservableList observableList = FXCollections.observableArrayList();// 循环遍历天数for (int i = 0; i < day; i++) {Calendar calendar = Calendar.getInstance();calendar.add(Calendar.DATE, -i);Date calendarTime = calendar.getTime();String date = dateTools.dateFormat(calendarTime, "yyyy-MM-dd");String dateInputsql = "select SUM(rMoney) from tb_records where rType='" + type + "' and rDate= '" + date + "' and " + "uId=" + user.getUserId() + ";";float dateInput = recordDao.getResultValueBySql(dateInputsql);observableList.add(new PieChart.Data(date, dateInput));}
// 设置饼图的标题pieChart.setTitle("饼图");// 顺时针设置饼图的切片pieChart.setClockwise(true);// 方法设置标签行的长度pieChart.setLabelLineLength(50);// 将饼图的标签设置为可见pieChart.setLabelsVisible(true);// 设置饼图的起始角度pieChart.setStartAngle(180);
pieChart.getData().clear();pieChart.setData(observableList);}
/*** 操作结果：设置饼图的数据根据给定的月数** @param month    给定的月数* @param pieChart 饼图* @param type     指定账目类型，收入或支出*/public void public_setMonthPieChartData(User user, int month, PieChart pieChart, String type) {// 实例化RecordDao对象RecordDao recordDao = new RecordDao();// 获取ObservableList集合对象ObservableList observableList = FXCollections.observableArrayList();for (int i = 0; i < month; i++) {Calendar calendar = Calendar.getInstance();calendar.setTime(new Date());calendar.add(calendar.MONDAY, -i);Date monthDate = calendar.getTime();String monthStringDate = dateTools.dateFormat(monthDate, "yyyy-MM");String monthsql = "select SUM(rMoney) from tb_records where rType='" + type + "' and MONTH(rDate)= MONTH" + "('" + dateTools.dateFormat(monthDate, "yyyy-MM-dd") + "') and uId=" + user.getUserId() + ";";Object monthResult = recordDao.getResultValueBySql(monthsql);observableList.add(new PieChart.Data(monthStringDate, (Float) monthResult));}
// 设置饼图的标题pieChart.setTitle("饼图");// 顺时针设置饼图的切片pieChart.setClockwise(true);// 方法设置标签行的长度pieChart.setLabelLineLength(50);// 将饼图的标签设置为可见pieChart.setLabelsVisible(true);// 设置饼图的起始角度pieChart.setStartAngle(180);
pieChart.getData().clear();pieChart.setData(observableList);}
/*** 操作结果：设置饼图的数据根据季度** @param pieChart 饼图* @param type     指定类型*/public void public_setSeasonPieChartData(User user, PieChart pieChart, String type) {ObservableList observableList = FXCollections.observableArrayList();List<Date[]> list = dateTools.getYearQuarterList(new Date());for (int i = 0; i < list.size(); i++) {String strDate = dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "-" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd");String seasonSql = "select SUM(rMoney) from tb_records where rType='" + type + "' and rDate between '" + dateTools.dateFormat(list.get(i)[0], "yyyy-MM-dd") + "' and '" + dateTools.dateFormat(list.get(i)[1], "yyyy-MM-dd") + "' and uId=" + user.getUserId() + ";";Object season = new RecordDao().getResultValueBySql(seasonSql);observableList.add(new PieChart.Data(strDate, (Float) season));}
// 设置饼图的标题pieChart.setTitle("饼图");// 顺时针设置饼图的切片pieChart.setClockwise(true);// 方法设置标签行的长度pieChart.setLabelLineLength(50);// 将饼图的标签设置为可见pieChart.setLabelsVisible(true);// 设置饼图的起始角度pieChart.setStartAngle(180);
pieChart.getData().clear();pieChart.getData().addAll(observableList);}
}

创建界面

创建条形图显示界面，在view包下新建barChartFrame.fxml文件，使用Scene Builder设计界面，各个控件的属性和事件方法参考下面的代码：

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.chart.BarChart?>
<?import javafx.scene.chart.CategoryAxis?>
<?import javafx.scene.chart.NumberAxis?>
<?import javafx.scene.control.ComboBox?>
<?import javafx.scene.control.ScrollPane?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.HBox?>
<AnchorPane prefHeight="800.0" prefWidth="800.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1"fx:controller="AccountSystem.controller.BarChartFrameController"><children><HBox alignment="CENTER" prefHeight="68.0" prefWidth="800.0"><children><ComboBox fx:id="barChart_comboBox" onAction="#barChart_comboBoxEvent" promptText="请选择日期"/></children></HBox><ScrollPane fitToHeight="true" fitToWidth="true" layoutY="74.0" prefHeight="725.0" prefWidth="800.0"><content><BarChart fx:id="barChart" prefHeight="727.0" prefWidth="799.0"><xAxis><CategoryAxis fx:id="categoryAxis" side="BOTTOM"/></xAxis><yAxis><NumberAxis fx:id="numberAxis" side="LEFT"/></yAxis></BarChart></content></ScrollPane></children>
</AnchorPane>

接着是在controller包下创建对应的控制器类BarChartFrameController.java，从Scene Builder中复制该界面的组件对象和事件方法代码到该控制器类中：

package AccountSystem.controller;

import AccountSystem.tools.ChartTools;
import AccountSystem.tools.PublicTools;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.chart.BarChart;
import javafx.scene.chart.CategoryAxis;
import javafx.scene.chart.NumberAxis;
import javafx.scene.control.ComboBox;

import java.util.Calendar;

/*** 条形图界面控制器** @author lck100*/
public class BarChartFrameController {private ChartTools chartTools = new ChartTools();private PublicTools publicTools = new PublicTools();
@FXMLprivate CategoryAxis categoryAxis;
@FXMLprivate BarChart<?, ?> barChart;
@FXMLprivate ComboBox<?> barChart_comboBox;
@FXMLprivate NumberAxis numberAxis;

/*** 下拉列表框事件处理** @param event 事件*/public void barChart_comboBoxEvent(ActionEvent event) {}
}

再接着就是这一FXML资源文件啊，所以继续在MainApp.java中写加载方法：

    /*** 操作结果：“条形图”查询结果界面*/public Scene initBarChart() {try {Parent page = FXMLLoader.load(getClass().getResource("view/barChartFrame.fxml"));
Stage mainFrameStage = new Stage();mainFrameStage.setTitle("条形图");mainFrameStage.setResizable(true);mainFrameStage.setAlwaysOnTop(false);mainFrameStage.initModality(Modality.APPLICATION_MODAL);mainFrameStage.initOwner(primaryStage);Scene scene = new Scene(page);mainFrameStage.setScene(scene);
mainFrameStage.showAndWait();return scene;} catch (IOException e) {e.printStackTrace();}return null;}

最后是在菜单项中进行调用在MainPageController.java类中：

    /*** ”条形图“菜单项的事件监听器** @param actionEvent 事件*/@FXMLpublic void barChartMenuItemEvent(ActionEvent actionEvent) {// 打开条形图界面mainApp.initBarChart();}

运行程序，查看界面：

实现功能

要实现通过下拉列表框来选择不同的选项来绘制不同的条形图，所以首先要为下拉列表框填充选项，接着为下拉列表框选项注册事件监听器，即选中的不同的日期就绘制不同的条形图。

即初始化下拉列表框选项的代码如下：

    /*** 初始化界面*/public void initialize() {// 初始化填充下拉列表框选项String[] items = new String[]{"今天", "昨天", "最近3天", "最近7天", "最近30天", "最近1年（12月）", "最近1年（4季度）"};publicTools.public_addComboBoxItems(barChart_comboBox, items);}

运行查看即是：

接着是监听下拉列表框选项的事件：

    /*** 下拉列表框事件处理** @param event 事件*/public void barChart_comboBoxEvent(ActionEvent event) {// 获取下拉列表框选中项String selectedCoboboxItem = (String) barChart_comboBox.getSelectionModel().selectedItemProperty().getValue();// 对下拉列表框选中项进行处理switch (selectedCoboboxItem) {case "今天":chartTools.public_setBarChartData(1, barChart, categoryAxis, numberAxis);break;case "昨天":chartTools.public_setBarChartData(2, barChart, categoryAxis, numberAxis);break;case "最近3天":chartTools.public_setBarChartData(3, barChart, categoryAxis, numberAxis);break;case "最近7天":chartTools.public_setBarChartData(7, barChart, categoryAxis, numberAxis);break;case "最近30天":chartTools.public_setBarChartData(30, barChart, categoryAxis, numberAxis);break;case "最近1年（12月）":Calendar calendar = Calendar.getInstance();int month = calendar.get(Calendar.MONDAY) + 1;chartTools.public_setMonthBarChartData(month, barChart, categoryAxis, numberAxis);break;case "最近1年（4季度）":chartTools.public_setSeasonBarChartData(barChart, categoryAxis, numberAxis);break;default:break;}}

可以看到上面的代码很简洁，因为都是调用了ChartTools.java类中的方法，这些方法都是自定义封装的，这些代码才是核心的，所以如果要想绘制条形图需要去看该类中的代码，每一个方法都有注释说明，如果是更详细的教程还是要参照官网学习。

运行代码测试功能：

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