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reportlab SimpleDocTemplate-设置具有可变行数的表的固定高度

reportlab python-3.x python

Ralf · 技术社区 · 7 年前

我试图在中生成PDF发票 Python 使用 reportlab

发票将只有一页,不会有比这一页上的空间更多的详细信息;我的代码在生成PDF之前检查最大数量的详细信息。

现在我在用 SimpleDocTemplate 要将所有内容添加到页面中,并构造我使用的 Table

from reportlab.lib.units import mm
from reportlab.platypus import Paragraph, Spacer, Table, TableStyle
from reportlab.platypus import SimpleDocTemplate

# add invoice header
flowable_list = [
    Spacer(1, 5*mm),
    Paragraph('Date: ...', pg_style_1),
    Spacer(1, 5*mm),
]

# add invoice details
detail_list = [
    ('Item 1', 8, 45),
    ('Item 2', 1, 14),
]
row_list = [
    [
        Paragraph(desc, pg_style_1),
        quantity,
        amount,
    ]
    for desc, quantity, amount in detail_list]
story.append(
    Table(
        data=row_list,
        colWidths=[100*mm, 40*mm, 40*mm],
        style=TableStyle([
            ('VALIGN', (0, 0), (-1, -1), 'TOP'),
            ... some other options ...
        ])))

# add invoice footer; this should be at a specific position on the page
flowable_list.append(Spacer(1, 5*mm))
flowable_list.append(Paragraph('Total: 0', pg_style_1))

# build PDF
buffer = io.BytesIO()
doc = SimpleDocTemplate(buffer)
doc.build(flowable_list)

我的问题: 底部的总金额每次都必须在特定的位置(比如 x*mm 从底部),但是可以有可变数量的细节,这会导致细节表具有非固定高度。

我目前的解决方案: Spacer 在表之后;这个间隔的高度必须根据表中的行数来计算(更多的行意味着间隔将更小;更少的行产生更大的间隔)。但如果其中一行环绕并占用的空间超过一行,则此操作将失败。

我的问题是: 简单模板 ?

This similar question 简单模板

0 回复 | 直到 7 年前

Jaco 7 年前

使用“TopPadder”尝试这个可行的示例(结果是总数被推到框架的底部,我假设您可以在下面添加一个缓冲垫,以控制从底部开始的高度):

########################################################################
from reportlab.lib.units import mm
from reportlab.platypus import Paragraph, Spacer, Table, TableStyle
from reportlab.lib.styles import getSampleStyleSheet
from reportlab.platypus import SimpleDocTemplate
from reportlab.platypus.flowables import TopPadder
import io

def create_pdf():

    styles=getSampleStyleSheet()

    # add invoice header
    flowable_list = [
        Spacer(1, 5 * mm),
        Paragraph(f'Date: ...', styles['Normal']),
        Spacer(1, 5 * mm),
    ]

    # add invoice details
    detail_list = [
        ('Item 1', 8, 45),
        ('Item 2', 1, 14),
    ]
    row_list = [
        [
            Paragraph(f'desc', styles['Normal']),
            # quantity,
            # amount,
        ]
        for desc, quantity, amount in detail_list]

    story = []
    story.append(
        Table(
            data=row_list,
            colWidths=[100 * mm, 40 * mm, 40 * mm],
            style=TableStyle([
                ('VALIGN', (0, 0), (-1, -1), 'TOP'),
                # ... some other options...
            ])))

    # add invoice footer; this should be at a specific position on the page
    flowable_list.append(Spacer(1, 5 * mm))
    flowable_list.append(TopPadder(Paragraph(f'Total: 0', styles['Normal'])))

    # build PDF
    buffer = io.BytesIO()
    doc = SimpleDocTemplate("test2.pdf")
    doc.build(flowable_list)

    # ----------------------------------------------------------------------
if __name__ == "__main__":
    create_pdf()  # Printing the pdf

Ralf 7 年前

...
story.append(
    Table(
        data=row_list,
        colWidths=[100*mm, 40*mm, 40*mm],
        style=TableStyle([
            ('VALIGN', (0, 0), (-1, -1), 'TOP'),
            ... some other options ...
        ])))

# calculate real height of details table, so we can add a 'Spacer' for the missing
# part to have the invoice totals at the correct height at the bottom of the page
_, real_height = story[-1].wrap(doc_width, doc_height)
height_reserved_for_details = 100*mm
remaining_height = max(0, height_reserved_for_details - real_height)
story.append(Spacer(1, remaining_height))

flowable_list.append(Paragraph('Total: 0', pg_style_1))