python3+PyQt5实现文档打印功能

#!/usr/bin/env python3
import math
import sys
import html
from PyQt5.QtPrintSupport import QPrinter,QPrintDialog
from PyQt5.QtCore import (QDate, QRectF, Qt)
from PyQt5.QtWidgets import (QApplication,QDialog, 
 QHBoxLayout,QPushButton, QTableWidget, QTableWidgetItem,QVBoxLayout)
from PyQt5.QtGui import (QFont,QFontMetrics,QPainter,QTextCharFormat,
  QTextCursor, QTextDocument, QTextFormat,
  QTextOption, QTextTableFormat,
  QPixmap,QTextBlockFormat)
import qrc_resources


from PyQt5.QtPrintSupport import QPrinter,QPrintDialog
from PyQt5.QtCore import (QDate, QRectF, Qt)
from PyQt5.QtWidgets import (QApplication,QDialog, 
 QHBoxLayout,QPushButton, QTableWidget, QTableWidgetItem,QVBoxLayout)
from PyQt5.QtGui import (QFont,QFontMetrics,QPainter,QTextCharFormat,
  QTextCursor, QTextDocument, QTextFormat,
  QTextOption, QTextTableFormat,
  QPixmap,QTextBlockFormat)
import qrc_resources
DATE_FORMAT = "MMM d, yyyy"


class Statement(object):

 def __init__(self, company, contact, address):
 self.company = company
 self.contact = contact
 self.address = address
 self.transactions = [] # List of (QDate, float) two-tuples


 def balance(self):
 return sum([amount for date, amount in self.transactions])


class Form(QDialog):

 def __init__(self, parent=None):
 super(Form, self).__init__(parent)

 self.printer = QPrinter()
 self.printer.setPageSize(QPrinter.Letter)
 self.generateFakeStatements()
 self.table = QTableWidget()
 self.populateTable()

 cursorButton = QPushButton("Print via Q&Cursor")
 htmlButton = QPushButton("Print via &HTML")
 painterButton = QPushButton("Print via Q&Painter")
 quitButton = QPushButton("&Quit")

 buttonLayout = QHBoxLayout()
 buttonLayout.addWidget(cursorButton)
 buttonLayout.addWidget(htmlButton)
 buttonLayout.addWidget(painterButton)
 buttonLayout.addStretch()
 buttonLayout.addWidget(quitButton)
 layout = QVBoxLayout()
 layout.addWidget(self.table)
 layout.addLayout(buttonLayout)
 self.setLayout(layout)

 cursorButton.clicked.connect(self.printViaQCursor)
 htmlButton.clicked.connect(self.printViaHtml)
 painterButton.clicked.connect(self.printViaQPainter)
 quitButton.clicked.connect(self.accept)

 self.setWindowTitle("Printing")


 def generateFakeStatements(self):
 self.statements = []
 statement = Statement("Consality", "Ms S. Royal",
 "234 Rue Saint Hyacinthe, 750201, Paris")
 statement.transactions.append((QDate(2007, 8, 11), 2342))
 statement.transactions.append((QDate(2007, 9, 10), 2342))
 statement.transactions.append((QDate(2007, 10, 9), 2352))
 statement.transactions.append((QDate(2007, 10, 17), -1500))
 statement.transactions.append((QDate(2007, 11, 12), 2352))
 statement.transactions.append((QDate(2007, 12, 10), 2352))
 statement.transactions.append((QDate(2007, 12, 20), -7500))
 statement.transactions.append((QDate(2007, 12, 20), 250))
 statement.transactions.append((QDate(2008, 1, 10), 2362))
 self.statements.append(statement)

 statement = Statement("Demamitur Plc", "Mr G. Brown",
 "14 Tall Towers, Tower Hamlets, London, WC1 3BX")
 statement.transactions.append((QDate(2007, 5, 21), 871))
 statement.transactions.append((QDate(2007, 6, 20), 542))
 statement.transactions.append((QDate(2007, 7, 20), 1123))
 statement.transactions.append((QDate(2007, 7, 20), -1928))
 statement.transactions.append((QDate(2007, 8, 13), -214))
 statement.transactions.append((QDate(2007, 9, 15), -3924))
 statement.transactions.append((QDate(2007, 9, 15), 2712))
 statement.transactions.append((QDate(2007, 9, 15), -273))
 #statement.transactions.append((QDate(2007, 11, 8), -728))
 #statement.transactions.append((QDate(2008, 2, 7), 228))
 #statement.transactions.append((QDate(2008, 3, 13), -508))
 #statement.transactions.append((QDate(2008, 3, 22), -2481))
 #statement.transactions.append((QDate(2008, 4, 5), 195))
 self.statements.append(statement)


 def populateTable(self):
 headers = ["Company", "Contact", "Address", "Balance"]
 self.table.setColumnCount(len(headers))
 self.table.setHorizontalHeaderLabels(headers)
 self.table.setRowCount(len(self.statements))
 for row, statement in enumerate(self.statements):
 self.table.setItem(row, 0, QTableWidgetItem(statement.company))
 self.table.setItem(row, 1, QTableWidgetItem(statement.contact))
 self.table.setItem(row, 2, QTableWidgetItem(statement.address))
 item = QTableWidgetItem("$ {0:,.2f}".format(float(statement.balance())))
 item.setTextAlignment(Qt.AlignRight|Qt.AlignVCenter)
 self.table.setItem(row, 3, item)
 self.table.resizeColumnsToContents()


 def printViaHtml(self):
 htmltext = ""
 for statement in self.statements:
 date = QDate.currentDate().toString(DATE_FORMAT)
 address = html.escape(statement.address).replace(
  ",", "<br>")
 contact = html.escape(statement.contact)
 balance = statement.balance()
 htmltext += ("<p align=right><img src=':/logo.png'></p>"
  "<p align=right>Greasy Hands Ltd."
  "<br>New Lombard Street"
  "<br>London<br>WC13 4PX<br>{0}</p>"
  "<p>{1}</p><p>Dear {2},</p>"
  "<p>The balance of your account is $ {3:,.2f}.").format(
  date, address, contact, float(balance))
 if balance < 0:
 htmltext += (" <p><font color=red><b>Please remit the "
  "amount owing immediately.</b></font>")
 else:
 htmltext += (" We are delighted to have done business "
  "with you.")
 htmltext += ("</p><p> </p><p>"
  "<table border=1 cellpadding=2 "
  "cellspacing=2><tr><td colspan=3>"
  "Transactions</td></tr>")
 for date, amount in statement.transactions:
 color, status = "black", "Credit"
 if amount < 0:
  color, status = "red", "Debit"
 htmltext += ("<tr><td align=right>{0}</td>"
  "<td>{1}</td><td align=right>"
  "<font color={2}>$ {3:,.2f}</font></td></tr>".format(
  date.toString(DATE_FORMAT), status, color,float(abs(amount))))
 htmltext += ("</table></p><p style='page-break-after:always;'>"
  "We hope to continue doing "
  "business with you,<br>Yours sincerely,"
  "<br><br>K. Longrey, Manager</p>")
 dialog = QPrintDialog(self.printer, self)
 if dialog.exec_():
 document = QTextDocument()
 document.setHtml(htmltext)
 document.print_(self.printer)

 def printViaQCursor(self):
 dialog = QPrintDialog(self.printer, self)
 if not dialog.exec_():
 return
 logo = QPixmap(":/logo.png")
 headFormat = QTextBlockFormat()
 headFormat.setAlignment(Qt.AlignLeft)
 headFormat.setTextIndent(
 self.printer.pageRect().width() - logo.width() - 216)
 bodyFormat = QTextBlockFormat()
 bodyFormat.setAlignment(Qt.AlignJustify)
 lastParaBodyFormat = QTextBlockFormat(bodyFormat)
 lastParaBodyFormat.setPageBreakPolicy(
 QTextFormat.PageBreak_AlwaysAfter)
 rightBodyFormat = QTextBlockFormat()
 rightBodyFormat.setAlignment(Qt.AlignRight)
 headCharFormat = QTextCharFormat()
 headCharFormat.setFont(QFont("Helvetica", 10))
 bodyCharFormat = QTextCharFormat()
 bodyCharFormat.setFont(QFont("Times", 11))
 redBodyCharFormat = QTextCharFormat(bodyCharFormat)
 redBodyCharFormat.setForeground(Qt.red)
 tableFormat = QTextTableFormat()
 tableFormat.setBorder(1)
 tableFormat.setCellPadding(2)

 document = QTextDocument()
 cursor = QTextCursor(document)
 mainFrame = cursor.currentFrame()
 page = 1
 for statement in self.statements:
 cursor.insertBlock(headFormat, headCharFormat)
 cursor.insertImage(":/logo.png")
 for text in ("Greasy Hands Ltd.", "New Lombard Street",
  "London", "WC13 4PX",
  QDate.currentDate().toString(DATE_FORMAT)):
 cursor.insertBlock(headFormat, headCharFormat)
 cursor.insertText(text)
 for line in statement.address.split(", "):
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 cursor.insertText(line)
 cursor.insertBlock(bodyFormat)
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 cursor.insertText("Dear {0},".format(statement.contact))
 cursor.insertBlock(bodyFormat)
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 balance = statement.balance()
 cursor.insertText("The balance of your account is $ {0:,.2f}.".format(float(balance)))
 if balance < 0:
 cursor.insertBlock(bodyFormat, redBodyCharFormat)
 cursor.insertText("Please remit the amount owing "
   "immediately.")
 else:
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 cursor.insertText("We are delighted to have done "
   "business with you.")
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 cursor.insertText("Transactions:")
 table = cursor.insertTable(len(statement.transactions), 3,
   tableFormat)
 row = 0
 for date, amount in statement.transactions:
 cellCursor = table.cellAt(row, 0).firstCursorPosition()
 cellCursor.setBlockFormat(rightBodyFormat)
 cellCursor.insertText(date.toString(DATE_FORMAT),
   bodyCharFormat)
 cellCursor = table.cellAt(row, 1).firstCursorPosition()
 if amount > 0:
  cellCursor.insertText("Credit", bodyCharFormat)
 else:
  cellCursor.insertText("Debit", bodyCharFormat)
 cellCursor = table.cellAt(row, 2).firstCursorPosition()
 cellCursor.setBlockFormat(rightBodyFormat)
 format = bodyCharFormat
 if amount < 0:
  format = redBodyCharFormat
 cellCursor.insertText("$ {0:,.2f}".format(float(amount)), format)
 row += 1
 cursor.setPosition(mainFrame.lastPosition())
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 cursor.insertText("We hope to continue doing business "
  "with you,")
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 cursor.insertText("Yours sincerely")
 cursor.insertBlock(bodyFormat)
 if page == len(self.statements):
 cursor.insertBlock(bodyFormat, bodyCharFormat)
 else:
 cursor.insertBlock(lastParaBodyFormat, bodyCharFormat)
 cursor.insertText("K. Longrey, Manager")
 page += 1
 document.print_(self.printer)


 def printViaQPainter(self):
 dialog = QPrintDialog(self.printer, self)
 if not dialog.exec_():
 return
 LeftMargin = 72
 sansFont = QFont("Helvetica", 10)
 sansLineHeight = QFontMetrics(sansFont).height()
 serifFont = QFont("Times", 11)
 fm = QFontMetrics(serifFont)
 DateWidth = fm.width(" September 99, 2999 ")
 CreditWidth = fm.width(" Credit ")
 AmountWidth = fm.width(" W999999.99 ")
 serifLineHeight = fm.height()
 logo = QPixmap(":/logo.png")
 painter = QPainter(self.printer)
 pageRect = self.printer.pageRect()
 page = 1
 for statement in self.statements:
 painter.save()
 y = 0
 x = pageRect.width() - logo.width() - LeftMargin
 painter.drawPixmap(x, 0, logo)
 y += logo.height() + sansLineHeight
 painter.setFont(sansFont)
 painter.drawText(x, y, "Greasy Hands Ltd.")
 y += sansLineHeight
 painter.drawText(x, y, "New Lombard Street")
 y += sansLineHeight
 painter.drawText(x, y, "London")
 y += sansLineHeight
 painter.drawText(x, y, "WC13 4PX")
 y += sansLineHeight
 painter.drawText(x, y,
  QDate.currentDate().toString(DATE_FORMAT))
 y += sansLineHeight
 painter.setFont(serifFont)
 x = LeftMargin
 for line in statement.address.split(", "):
 painter.drawText(x, y, line)
 y += serifLineHeight
 y += serifLineHeight
 painter.drawText(x, y, "Dear {0},".format(statement.contact))
 y += serifLineHeight

 balance = statement.balance()
 painter.drawText(x, y, "The balance of your account is $ {0:,.2f}".format(float(balance)))
 y += serifLineHeight
 if balance < 0:
 painter.setPen(Qt.red)
 text = "Please remit the amount owing immediately."
 else:
 text = ("We are delighted to have done business "
  "with you.")
 painter.drawText(x, y, text)
 painter.setPen(Qt.black)
 y += int(serifLineHeight * 1.5)
 painter.drawText(x, y, "Transactions:")
 y += serifLineHeight

 option = QTextOption(Qt.AlignRight|Qt.AlignVCenter)
 for date, amount in statement.transactions:
 x = LeftMargin
 h = int(fm.height() * 1.3)
 painter.drawRect(x, y, DateWidth, h)
 painter.drawText(
  QRectF(x + 3, y + 3, DateWidth - 6, h - 6),
  date.toString(DATE_FORMAT), option)
 x += DateWidth
 painter.drawRect(x, y, CreditWidth, h)
 text = "Credit"
 if amount < 0:
  text = "Debit"
 painter.drawText(
  QRectF(x + 3, y + 3, CreditWidth - 6, h - 6),
  text, option)
 x += CreditWidth
 painter.drawRect(x, y, AmountWidth, h)
 if amount < 0:
  painter.setPen(Qt.red)
 painter.drawText(
  QRectF(x + 3, y + 3, AmountWidth - 6, h - 6),
  "$ {0:,.2f}".format(float(amount)),
  option)
 painter.setPen(Qt.black)
 y += h
 y += serifLineHeight
 x = LeftMargin
 painter.drawText(x, y, "We hope to continue doing "
   "business with you,")
 y += serifLineHeight
 painter.drawText(x, y, "Yours sincerely")
 y += serifLineHeight * 3
 painter.drawText(x, y, "K. Longrey, Manager")
 x = LeftMargin
 y = pageRect.height() - 72
 painter.drawLine(x, y, pageRect.width() - LeftMargin, y)
 y += 2
 font = QFont("Helvetica", 9)
 font.setItalic(True)
 painter.setFont(font)
 option = QTextOption(Qt.AlignCenter)
 option.setWrapMode(QTextOption.WordWrap)
 painter.drawText(
  QRectF(x, y, pageRect.width() - 2 * LeftMargin, 31),
  "The contents of this letter are for information "
  "only and do not form part of any contract.",
  option)
 page += 1
 if page <= len(self.statements):
 self.printer.newPage()
 painter.restore()


if __name__ == "__main__":
 app = QApplication(sys.argv)
 form = Form()
 form.show()
 app.exec_()