如何在ReportLab的PDF输出中重复表格列标题

Question

我正在使用ReportLab在PDF文档中编写表格,并对结果非常满意(尽管还没有完全掌握Flowables).

但是,我无法弄清楚如何使一个跨越分页符的表重复其列标题.

下面的代码在C:\ Temp中创建一个test.pdf,它有一个标题行,后跟99行数据.

标题行在第一页看起来很棒,但我希望在第二页和第三页的顶部重复.

我很想知道使用SimpleDocTemplate完成任何方法的方法.

from reportlab.platypus import SimpleDocTemplate, Table, TableStyle, Paragraph, Frame, Spacer
from reportlab.lib import colors
from reportlab.lib.units import cm
from reportlab.lib.pagesizes import A3, A4, landscape, portrait
from reportlab.lib.styles import ParagraphStyle, getSampleStyleSheet
from reportlab.lib.enums import TA_LEFT, TA_RIGHT, TA_CENTER, TA_JUSTIFY
from reportlab.pdfgen import canvas

pdfReportPages = "C:\\Temp\\test.pdf"
doc = SimpleDocTemplate(pdfReportPages, pagesize=A4)

# container for the "Flowable" objects
elements = []
styles=getSampleStyleSheet()
styleN = styles["Normal"]

# Make heading for each column
column1Heading = Paragraph("<para align=center>COLUMN ONE HEADING</para>",styles['Normal'])
column2Heading = Paragraph("<para align=center>COLUMN TWO HEADING</para>",styles['Normal'])
row_array = [column1Heading,column2Heading]
tableHeading = [row_array]
tH = Table(tableHeading, [6 * cm, 6 * cm])            # These are the column widths for the headings on the table
tH.hAlign = 'LEFT'
tblStyle = TableStyle([('TEXTCOLOR',(0,0),(-1,-1),colors.black),
                       ('VALIGN',(0,0),(-1,-1),'TOP'),
                       ('BOX',(0,0),(-1,-1),1,colors.black),
                       ('BOX',(0,0),(0,-1),1,colors.black)])
tblStyle.add('BACKGROUND',(0,0),(-1,-1),colors.lightblue)
tH.setStyle(tblStyle)
elements.append(tH)

# Assemble rows of data for each column
for i in range(1,100):
    column1Data = Paragraph("<para align=center> " + "Row " + str(i) + " Column 1 Data" + "</font> </para>",styles['Normal'])
    column2Data = Paragraph("<para align=center> " + "Row " + str(i) + " Column 2 Data" + "</font> </para>",styles['Normal'])
    row_array = [column1Data,column2Data]
    tableRow = [row_array]
    tR=Table(tableRow, [6 * cm, 6 * cm])   
    tR.hAlign = 'LEFT'
    tR.setStyle(TableStyle([('BACKGROUND',(0,0),(-1,-1),colors.white),
                            ('TEXTCOLOR',(0,0),(-1,-1),colors.black),
                            ('VALIGN',(0,0),(-1,-1),'TOP'),
                            ('BOX',(0,0),(-1,-1),1,colors.black),
                            ('BOX',(0,0),(0,-1),1,colors.black)]))
    elements.append(tR)
    del tR

elements.append(Spacer(1, 0.3 * cm))

doc.build(elements)

Answer 1

这是我开发的代码,遵循Gordon的建议重新考虑使用repeatRows,它的工作原理!

from reportlab.platypus import SimpleDocTemplate, Table, TableStyle, Paragraph, Frame, Spacer
from reportlab.lib import colors
from reportlab.lib.units import cm
from reportlab.lib.pagesizes import A3, A4, landscape, portrait
from reportlab.lib.styles import ParagraphStyle, getSampleStyleSheet
from reportlab.lib.enums import TA_LEFT, TA_RIGHT, TA_CENTER, TA_JUSTIFY
from reportlab.pdfgen import canvas

pdfReportPages = "C:\\Temp\\test.pdf"
doc = SimpleDocTemplate(pdfReportPages, pagesize=A4)

# container for the "Flowable" objects
elements = []
styles=getSampleStyleSheet()
styleN = styles["Normal"]

# Make heading for each column and start data list
column1Heading = "COLUMN ONE HEADING"
column2Heading = "COLUMN TWO HEADING"
# Assemble data for each column using simple loop to append it into data list
data = [[column1Heading,column2Heading]]
for i in range(1,100):
    data.append([str(i),str(i)])

tableThatSplitsOverPages = Table(data, [6 * cm, 6 * cm], repeatRows=1)
tableThatSplitsOverPages.hAlign = 'LEFT'
tblStyle = TableStyle([('TEXTCOLOR',(0,0),(-1,-1),colors.black),
                       ('VALIGN',(0,0),(-1,-1),'TOP'),
                       ('LINEBELOW',(0,0),(-1,-1),1,colors.black),
                       ('BOX',(0,0),(-1,-1),1,colors.black),
                       ('BOX',(0,0),(0,-1),1,colors.black)])
tblStyle.add('BACKGROUND',(0,0),(1,0),colors.lightblue)
tblStyle.add('BACKGROUND',(0,1),(-1,-1),colors.white)
tableThatSplitsOverPages.setStyle(tblStyle)
elements.append(tableThatSplitsOverPages)

doc.build(elements)

Answer 2

从文档中(是的,我知道,但有时很难在手册中找到这些内容):

repeatRows参数指定在要求表自行拆分时应重复的前导行数.

因此,当您创建表时,这是您可以传递的参数之一,它会将前n行转换为重复的标题行.您可以在第77页找到该部分文本,但有关创建表的部分从第76页开始.

http://www.reportlab.com/docs/reportlab-userguide.pdf

Answer 3

创建表时使用repeatRows=1...

from reportlab.platypus import Table 
Table(data,repeatRows=1)

我总是喜欢有一些东西可以剪切并粘贴到 .py 文件中来运行和测试。所以这里是...

import os
import pandas as pd
import numpy as np
import reportlab.platypus 
import reportlab.lib.styles
from reportlab.lib import colors
from reportlab.lib.units import mm
from reportlab.lib.pagesizes import letter, landscape

reportoutputfilepath = os.path.join('.\\test.pdf')

pdf_file = reportlab.platypus.SimpleDocTemplate(
                            reportoutputfilepath,
                            pagesize=landscape(letter),
                            rightMargin=10,
                            leftMargin=10,
                            topMargin=38,
                            bottomMargin=23
                    )
ts_tables = [
         ('ALIGN', (4,0), (-1,-1), 'RIGHT'),
         ('LINEBELOW', (0,0), (-1,0), 1, colors.purple),
         ('FONT', (0,0), (-1,0), 'Times-Bold'),
         ('LINEABOVE', (0,-1), (-1,-1), 1, colors.purple),
         ('FONT', (0,-1), (-1,-1), 'Times-Bold'),
         ('BACKGROUND',(1,1),(-2,-2),colors.white),
         ('TEXTCOLOR',(0,0),(1,-1),colors.black),
         ('FONTSIZE', (0,0),(-1,-1), 8), 
         ]

df = pd.DataFrame(np.random.randint(0,1000,size=(1000, 4)), columns=list('ABCD'))
lista = [df.columns[:,].values.astype(str).tolist()] + df.values.tolist()

#Here is where you put repeatRows=1
table = reportlab.platypus.Table(lista, colWidths=(20*mm, 20*mm, 20*mm, 20*mm),repeatRows=1)
table_style = reportlab.platypus.TableStyle(ts_tables)
table.setStyle(table_style)
elements = []
elements.append(table)

# Build the PDF
pdf_file.build(elements)
print reportoutputfilepath