问题
I want to preview, and then print, a report through a printer using PyQt. I tried the following code :
printer = QtGui.QPrinter()
doc = QtGui.QTextDocument("testing")
dialog = QtGui.QPrintDialog(printer)
dialog.setModal(True)
dialog.setWindowTitle("printerrr")
pdialog = QtGui.QPrintPreviewDialog(printer)
pdialog.setWindowFlags(QtCore.Qt.Window)
pdialog.exec_()
How I can preview my report then print it?
回答1:
Basic demo of Qt's print dialogs:
PyQt4
import sys, os
from PyQt4 import QtGui, QtCore
class Window(QtGui.QWidget):
def __init__(self):
super(Window, self).__init__()
self.setWindowTitle('Document Printer')
self.editor = QtGui.QTextEdit(self)
self.editor.textChanged.connect(self.handleTextChanged)
self.buttonOpen = QtGui.QPushButton('Open', self)
self.buttonOpen.clicked.connect(self.handleOpen)
self.buttonPrint = QtGui.QPushButton('Print', self)
self.buttonPrint.clicked.connect(self.handlePrint)
self.buttonPreview = QtGui.QPushButton('Preview', self)
self.buttonPreview.clicked.connect(self.handlePreview)
layout = QtGui.QGridLayout(self)
layout.addWidget(self.editor, 0, 0, 1, 3)
layout.addWidget(self.buttonOpen, 1, 0)
layout.addWidget(self.buttonPrint, 1, 1)
layout.addWidget(self.buttonPreview, 1, 2)
self.handleTextChanged()
def handleOpen(self):
path = QtGui.QFileDialog.getOpenFileName(
self, 'Open file', '',
'HTML files (*.html);;Text files (*.txt)')
if path:
file = QtCore.QFile(path)
if file.open(QtCore.QIODevice.ReadOnly):
stream = QtCore.QTextStream(file)
text = stream.readAll()
info = QtCore.QFileInfo(path)
if info.completeSuffix() == 'html':
self.editor.setHtml(text)
else:
self.editor.setPlainText(text)
file.close()
def handlePrint(self):
dialog = QtGui.QPrintDialog()
if dialog.exec_() == QtGui.QDialog.Accepted:
self.editor.document().print_(dialog.printer())
def handlePreview(self):
dialog = QtGui.QPrintPreviewDialog()
dialog.paintRequested.connect(self.editor.print_)
dialog.exec_()
def handleTextChanged(self):
enable = not self.editor.document().isEmpty()
self.buttonPrint.setEnabled(enable)
self.buttonPreview.setEnabled(enable)
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
window = Window()
window.resize(640, 480)
window.show()
sys.exit(app.exec_())
PyQt5
import sys, os
from PyQt5 import QtCore, QtWidgets, QtPrintSupport
class Window(QtWidgets.QWidget):
def __init__(self):
super(Window, self).__init__()
self.setWindowTitle('Document Printer')
self.editor = QtWidgets.QTextEdit(self)
self.editor.textChanged.connect(self.handleTextChanged)
self.buttonOpen = QtWidgets.QPushButton('Open', self)
self.buttonOpen.clicked.connect(self.handleOpen)
self.buttonPrint = QtWidgets.QPushButton('Print', self)
self.buttonPrint.clicked.connect(self.handlePrint)
self.buttonPreview = QtWidgets.QPushButton('Preview', self)
self.buttonPreview.clicked.connect(self.handlePreview)
layout = QtWidgets.QGridLayout(self)
layout.addWidget(self.editor, 0, 0, 1, 3)
layout.addWidget(self.buttonOpen, 1, 0)
layout.addWidget(self.buttonPrint, 1, 1)
layout.addWidget(self.buttonPreview, 1, 2)
self.handleTextChanged()
def handleOpen(self):
path = QtWidgets.QFileDialog.getOpenFileName(
self, 'Open file', '',
'HTML files (*.html);;Text files (*.txt)')[0]
if path:
file = QtCore.QFile(path)
if file.open(QtCore.QIODevice.ReadOnly):
stream = QtCore.QTextStream(file)
text = stream.readAll()
info = QtCore.QFileInfo(path)
if info.completeSuffix() == 'html':
self.editor.setHtml(text)
else:
self.editor.setPlainText(text)
file.close()
def handlePrint(self):
dialog = QtPrintSupport.QPrintDialog()
if dialog.exec_() == QtWidgets.QDialog.Accepted:
self.editor.document().print_(dialog.printer())
def handlePreview(self):
dialog = QtPrintSupport.QPrintPreviewDialog()
dialog.paintRequested.connect(self.editor.print_)
dialog.exec_()
def handleTextChanged(self):
enable = not self.editor.document().isEmpty()
self.buttonPrint.setEnabled(enable)
self.buttonPreview.setEnabled(enable)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
window = Window()
window.resize(640, 480)
window.show()
sys.exit(app.exec_())
EDIT
To print-preview a graphics view, use its render method:
def handlePreview(self):
# dialog = QtPrintSupport.QPrintPreviewDialog() # PyQt5
dialog = QtGui.QPrintPreviewDialog()
dialog.paintRequested.connect(self.handlePaintRequest)
dialog.exec_()
def handlePaintRequest(self, printer):
self.view.render(QtGui.QPainter(printer))
回答2:
A PyQt5 update to the example by ekhumoro providing print preview and print for a Chart:
from PyQt5 import QtChart, QtCore, QtGui, QtPrintSupport, QtWidgets
import sys
import random
class Window(QtWidgets.QWidget):
def __init__(self):
QtWidgets.QWidget.__init__(self)
self.setWindowTitle(self.tr('Chart Printing'))
self.chart = QtChart.QChart()
self.chart_view = QtChart.QChartView(self.chart)
self.chart_view.setRenderHint(QtGui.QPainter.Antialiasing)
self.buttonPreview = QtWidgets.QPushButton('Preview', self)
self.buttonPreview.clicked.connect(self.handle_preview)
self.buttonPrint = QtWidgets.QPushButton('Print', self)
self.buttonPrint.clicked.connect(self.handle_print)
layout = QtWidgets.QGridLayout(self)
layout.addWidget(self.chart_view, 0, 0, 1, 2)
layout.addWidget(self.buttonPreview, 1, 0)
layout.addWidget(self.buttonPrint, 1, 1)
self.create_chart()
def create_chart(self):
self.chart.setTitle("Chart Print Preview and Print Example")
for i in range(5):
series = QtChart.QLineSeries()
series.setName("Line {}".format(i + 1))
series.append(0, 0)
for i in range(1, 10):
series.append(i, random.randint(1, 9))
series.append(10, 10)
self.chart.addSeries(series)
self.chart.createDefaultAxes()
def handle_print(self):
printer = QtPrintSupport.QPrinter(QtPrintSupport.QPrinter.HighResolution)
dialog = QtPrintSupport.QPrintDialog(printer, self)
if dialog.exec_() == QtPrintSupport.QPrintDialog.Accepted:
self.handle_paint_request(printer)
def handle_preview(self):
dialog = QtPrintSupport.QPrintPreviewDialog()
dialog.paintRequested.connect(self.handle_paint_request)
dialog.exec_()
def handle_paint_request(self, printer):
painter = QtGui.QPainter(printer)
painter.setViewport(self.chart_view.rect())
painter.setWindow(self.chart_view.rect())
self.chart_view.render(painter)
painter.end()
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
window = Window()
window.resize(640, 480)
window.show()
sys.exit(app.exec_())
Edit: For the above demo code to run on Windows, then it requires:
> pip install PyQt5
> pip install pyqt5-tools
> pip install PyQtChart
来源：https://stackoverflow.com/questions/8193920/how-to-use-qprinter-and-qprintpreviewdialog