2021年4月5日

时间:1.5个小时左右

代码:300行左右

博客:1

知识点:使用jxl快速生成exel表格

今天尝试了生成表格的操作，查资料：

在Android开发时，有些时候需要把app中List<Object>集合数据，导出到Excel表中，方便进一步操作。Android可以使用jxl或poi来导出Excel，关于jxl和poi的比较网上有很多说法，不过统一的说法就是jxl的操作比poi简单，但是其功能略低于poi，但是个人认为对于简单的表格导出，使用jxl就足够了。本文以jxl为例，快速导出Excel表格。

第一步、下载并导入jxl.jar包

jxl.jar包的下载地址：http://jexcelapi.sourceforge.net/

第二步、生成表格

模拟数据、调用工具类生成表格

package teprinciple.yang.list2excel;

import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import com.shidian.excel.ExcelUtils;
import java.io.File;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private ArrayList<ArrayList<String>> recordList;
    private List<Student> students;
    private static String[] title = { "编号","姓名","性别","年龄","班级","数学","英语","语文" };
    private File file;
    private String fileName;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //模拟数据集合
        students = new ArrayList<>();
        for (int i = 1; i <= 10; i++) {
            students.add(new Student("小红"+i,"女","12","1"+i,"一班","85","77","98"));
            students.add(new Student("小明"+i,"男","14","2"+i,"二班","65","57","100"));
        }
    }

    /**
     * 导出excel
     * @param view
     */
    public void exportExcel(View view) {
        file = new File(getSDPath() + "/Record");
        makeDir(file);
        ExcelUtils.initExcel(file.toString() + "/成绩表.xls", title);
        fileName = getSDPath() + "/Record/成绩表.xls";
        ExcelUtils.writeObjListToExcel(getRecordData(), fileName, this);
    }

    /**
     * 将数据集合 转化成ArrayList<ArrayList<String>> 
     * @return
     */
    private  ArrayList<ArrayList<String>> getRecordData() {
        recordList = new ArrayList<>();
        for (int i = 0; i <students.size(); i++) {
            Student student = students.get(i);
            ArrayList<String> beanList = new ArrayList<String>();
            beanList.add(student.id);
            beanList.add(student.name);
            beanList.add(student.sex);
            beanList.add(student.age);
            beanList.add(student.classNo);
            beanList.add(student.math);
            beanList.add(student.english);
            beanList.add(student.chinese);
            recordList.add(beanList);
        }
        return recordList;
    }

    private  String getSDPath() {
        File sdDir = null;
        boolean sdCardExist = Environment.getExternalStorageState().equals(
                android.os.Environment.MEDIA_MOUNTED);
        if (sdCardExist) {
            sdDir = Environment.getExternalStorageDirectory();
        }
        String dir = sdDir.toString();
        return dir;
    }

    public  void makeDir(File dir) {
        if (!dir.getParentFile().exists()) {
            makeDir(dir.getParentFile());
        }
        dir.mkdir();
    }
}

生成表格的核心工具类:

package com.shidian.excel;

import android.content.Context;
import android.util.Log;
import android.widget.Toast;


import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import jxl.Workbook;
import jxl.WorkbookSettings;
import jxl.format.Colour;
import jxl.write.Label;
import jxl.write.WritableCell;
import jxl.write.WritableCellFormat;
import jxl.write.WritableFont;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;
import jxl.write.WriteException;

public class ExcelUtils {
    public static WritableFont arial14font = null;

    public static WritableCellFormat arial14format = null;
    public static WritableFont arial10font = null;
    public static WritableCellFormat arial10format = null;
    public static WritableFont arial12font = null;
    public static WritableCellFormat arial12format = null;

    public final static String UTF8_ENCODING = "UTF-8";
    public final static String GBK_ENCODING = "GBK";


    /**
     * 单元格的格式设置 字体大小 颜色 对齐方式、背景颜色等...
     */
    public static void format() {
        try {
            arial14font = new WritableFont(WritableFont.ARIAL, 14, WritableFont.BOLD);
            arial14font.setColour(jxl.format.Colour.LIGHT_BLUE);
            arial14format = new WritableCellFormat(arial14font);
            arial14format.setAlignment(jxl.format.Alignment.CENTRE);
            arial14format.setBorder(jxl.format.Border.ALL,jxl.format.BorderLineStyle.THIN);
            arial14format.setBackground(jxl.format.Colour.VERY_LIGHT_YELLOW);

            arial10font = new WritableFont(WritableFont.ARIAL, 10, WritableFont.BOLD);
            arial10format = new WritableCellFormat(arial10font);
            arial10format.setAlignment(jxl.format.Alignment.CENTRE);
            arial10format.setBorder(jxl.format.Border.ALL,jxl.format.BorderLineStyle.THIN);
            arial10format.setBackground(Colour.GRAY_25);

            arial12font = new WritableFont(WritableFont.ARIAL, 10);
            arial12format = new WritableCellFormat(arial12font);
            arial10format.setAlignment(jxl.format.Alignment.CENTRE);//对齐格式
            arial12format.setBorder(jxl.format.Border.ALL,jxl.format.BorderLineStyle.THIN); //设置边框

        } catch (WriteException e) {
            e.printStackTrace();
        }
    }

    /**
     * 初始化Excel
     * @param fileName
     * @param colName
     */
    public static void initExcel(String fileName, String[] colName) {
        format();
        WritableWorkbook workbook = null;
        try {
            File file = new File(fileName);
            if (!file.exists()) {
                file.createNewFile();
            }
            workbook = Workbook.createWorkbook(file);
            WritableSheet sheet = workbook.createSheet("成绩表", 0);
            //创建标题栏
            sheet.addCell((WritableCell) new Label(0, 0, fileName,arial14format));
            for (int col = 0; col < colName.length; col++) {
                sheet.addCell(new Label(col, 0, colName[col], arial10format));
            }
            sheet.setRowView(0,340); //设置行高

            workbook.write();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (workbook != null) {
                try {
                    workbook.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }

    @SuppressWarnings("unchecked")
    public static <T> void writeObjListToExcel(List<T> objList,String fileName, Context c) {
        if (objList != null && objList.size() > 0) {
            WritableWorkbook writebook = null;
            InputStream in = null;
            try {
                WorkbookSettings setEncode = new WorkbookSettings();
                setEncode.setEncoding(UTF8_ENCODING);
                in = new FileInputStream(new File(fileName));
                Workbook workbook = Workbook.getWorkbook(in);
                writebook = Workbook.createWorkbook(new File(fileName),workbook);
                WritableSheet sheet = writebook.getSheet(0);

//              sheet.mergeCells(0,1,0,objList.size()); //合并单元格
//              sheet.mergeCells()

                for (int j = 0; j < objList.size(); j++) {
                    ArrayList<String> list = (ArrayList<String>) objList.get(j);
                    for (int i = 0; i < list.size(); i++) {
                        sheet.addCell(new Label(i, j + 1, list.get(i),arial12format));
                        if (list.get(i).length() <= 5){
                            sheet.setColumnView(i,list.get(i).length()+8); //设置列宽
                        }else {
                            sheet.setColumnView(i,list.get(i).length()+5); //设置列宽
                        }
                    }
                    sheet.setRowView(j+1,350); //设置行高
                }

                writebook.write();
                Toast.makeText(c, "导出到手机存储中文件夹Record成功", Toast.LENGTH_SHORT).show();
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (writebook != null) {
                    try {
                        writebook.close();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }

                }
                if (in != null) {
                    try {
                        in.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }

        }
    }
}

这样就在手机的文件夹中生成成绩表.xls表。
注意：需要添加WRITE_EXTERNAL_STORAGE权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

更多关于jxl的相关方法可以参考文档：http://jexcelapi.sourceforge.net/resources/javadocs/current/docs/
poi的相关内容：https://poi.apache.org/

参考：https://www.jianshu.com/p/d3d40a69a9b1