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Image Viewer Example by PyQt5 and Python 3
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| #!/usr/bin/python3 | |
| # -*- coding: utf-8 -*- | |
| from PyQt5.QtCore import Qt | |
| from PyQt5.QtGui import QImage, QPixmap, QPalette, QPainter | |
| from PyQt5.QtPrintSupport import QPrintDialog, QPrinter | |
| from PyQt5.QtWidgets import QLabel, QSizePolicy, QScrollArea, QMessageBox, QMainWindow, QMenu, QAction, \ | |
| qApp, QFileDialog | |
| class QImageViewer(QMainWindow): | |
| def __init__(self): | |
| super().__init__() | |
| self.printer = QPrinter() | |
| self.scaleFactor = 0.0 | |
| self.imageLabel = QLabel() | |
| self.imageLabel.setBackgroundRole(QPalette.Base) | |
| self.imageLabel.setSizePolicy(QSizePolicy.Ignored, QSizePolicy.Ignored) | |
| self.imageLabel.setScaledContents(True) | |
| self.scrollArea = QScrollArea() | |
| self.scrollArea.setBackgroundRole(QPalette.Dark) | |
| self.scrollArea.setWidget(self.imageLabel) | |
| self.scrollArea.setVisible(False) | |
| self.setCentralWidget(self.scrollArea) | |
| self.createActions() | |
| self.createMenus() | |
| self.setWindowTitle("Image Viewer") | |
| self.resize(800, 600) | |
| def open(self): | |
| options = QFileDialog.Options() | |
| # fileName = QFileDialog.getOpenFileName(self, "Open File", QDir.currentPath()) | |
| fileName, _ = QFileDialog.getOpenFileName(self, 'QFileDialog.getOpenFileName()', '', | |
| 'Images (*.png *.jpeg *.jpg *.bmp *.gif)', options=options) | |
| if fileName: | |
| image = QImage(fileName) | |
| if image.isNull(): | |
| QMessageBox.information(self, "Image Viewer", "Cannot load %s." % fileName) | |
| return | |
| self.imageLabel.setPixmap(QPixmap.fromImage(image)) | |
| self.scaleFactor = 1.0 | |
| self.scrollArea.setVisible(True) | |
| self.printAct.setEnabled(True) | |
| self.fitToWindowAct.setEnabled(True) | |
| self.updateActions() | |
| if not self.fitToWindowAct.isChecked(): | |
| self.imageLabel.adjustSize() | |
| def print_(self): | |
| dialog = QPrintDialog(self.printer, self) | |
| if dialog.exec_(): | |
| painter = QPainter(self.printer) | |
| rect = painter.viewport() | |
| size = self.imageLabel.pixmap().size() | |
| size.scale(rect.size(), Qt.KeepAspectRatio) | |
| painter.setViewport(rect.x(), rect.y(), size.width(), size.height()) | |
| painter.setWindow(self.imageLabel.pixmap().rect()) | |
| painter.drawPixmap(0, 0, self.imageLabel.pixmap()) | |
| def zoomIn(self): | |
| self.scaleImage(1.25) | |
| def zoomOut(self): | |
| self.scaleImage(0.8) | |
| def normalSize(self): | |
| self.imageLabel.adjustSize() | |
| self.scaleFactor = 1.0 | |
| def fitToWindow(self): | |
| fitToWindow = self.fitToWindowAct.isChecked() | |
| self.scrollArea.setWidgetResizable(fitToWindow) | |
| if not fitToWindow: | |
| self.normalSize() | |
| self.updateActions() | |
| def about(self): | |
| QMessageBox.about(self, "About Image Viewer", | |
| "<p>The <b>Image Viewer</b> example shows how to combine " | |
| "QLabel and QScrollArea to display an image. QLabel is " | |
| "typically used for displaying text, but it can also display " | |
| "an image. QScrollArea provides a scrolling view around " | |
| "another widget. If the child widget exceeds the size of the " | |
| "frame, QScrollArea automatically provides scroll bars.</p>" | |
| "<p>The example demonstrates how QLabel's ability to scale " | |
| "its contents (QLabel.scaledContents), and QScrollArea's " | |
| "ability to automatically resize its contents " | |
| "(QScrollArea.widgetResizable), can be used to implement " | |
| "zooming and scaling features.</p>" | |
| "<p>In addition the example shows how to use QPainter to " | |
| "print an image.</p>") | |
| def createActions(self): | |
| self.openAct = QAction("&Open...", self, shortcut="Ctrl+O", triggered=self.open) | |
| self.printAct = QAction("&Print...", self, shortcut="Ctrl+P", enabled=False, triggered=self.print_) | |
| self.exitAct = QAction("E&xit", self, shortcut="Ctrl+Q", triggered=self.close) | |
| self.zoomInAct = QAction("Zoom &In (25%)", self, shortcut="Ctrl++", enabled=False, triggered=self.zoomIn) | |
| self.zoomOutAct = QAction("Zoom &Out (25%)", self, shortcut="Ctrl+-", enabled=False, triggered=self.zoomOut) | |
| self.normalSizeAct = QAction("&Normal Size", self, shortcut="Ctrl+S", enabled=False, triggered=self.normalSize) | |
| self.fitToWindowAct = QAction("&Fit to Window", self, enabled=False, checkable=True, shortcut="Ctrl+F", | |
| triggered=self.fitToWindow) | |
| self.aboutAct = QAction("&About", self, triggered=self.about) | |
| self.aboutQtAct = QAction("About &Qt", self, triggered=qApp.aboutQt) | |
| def createMenus(self): | |
| self.fileMenu = QMenu("&File", self) | |
| self.fileMenu.addAction(self.openAct) | |
| self.fileMenu.addAction(self.printAct) | |
| self.fileMenu.addSeparator() | |
| self.fileMenu.addAction(self.exitAct) | |
| self.viewMenu = QMenu("&View", self) | |
| self.viewMenu.addAction(self.zoomInAct) | |
| self.viewMenu.addAction(self.zoomOutAct) | |
| self.viewMenu.addAction(self.normalSizeAct) | |
| self.viewMenu.addSeparator() | |
| self.viewMenu.addAction(self.fitToWindowAct) | |
| self.helpMenu = QMenu("&Help", self) | |
| self.helpMenu.addAction(self.aboutAct) | |
| self.helpMenu.addAction(self.aboutQtAct) | |
| self.menuBar().addMenu(self.fileMenu) | |
| self.menuBar().addMenu(self.viewMenu) | |
| self.menuBar().addMenu(self.helpMenu) | |
| def updateActions(self): | |
| self.zoomInAct.setEnabled(not self.fitToWindowAct.isChecked()) | |
| self.zoomOutAct.setEnabled(not self.fitToWindowAct.isChecked()) | |
| self.normalSizeAct.setEnabled(not self.fitToWindowAct.isChecked()) | |
| def scaleImage(self, factor): | |
| self.scaleFactor *= factor | |
| self.imageLabel.resize(self.scaleFactor * self.imageLabel.pixmap().size()) | |
| self.adjustScrollBar(self.scrollArea.horizontalScrollBar(), factor) | |
| self.adjustScrollBar(self.scrollArea.verticalScrollBar(), factor) | |
| self.zoomInAct.setEnabled(self.scaleFactor < 3.0) | |
| self.zoomOutAct.setEnabled(self.scaleFactor > 0.333) | |
| def adjustScrollBar(self, scrollBar, factor): | |
| scrollBar.setValue(int(factor * scrollBar.value() | |
| + ((factor - 1) * scrollBar.pageStep() / 2))) | |
| if __name__ == '__main__': | |
| import sys | |
| from PyQt5.QtWidgets import QApplication | |
| app = QApplication(sys.argv) | |
| imageViewer = QImageViewer() | |
| imageViewer.show() | |
| sys.exit(app.exec_()) | |
| # TODO QScrollArea support mouse | |
| # base on https://github.com/baoboa/pyqt5/blob/master/examples/widgets/imageviewer.py | |
| # | |
| # if you need Two Image Synchronous Scrolling in the window by PyQt5 and Python 3 | |
| # please visit https://gist.github.com/acbetter/e7d0c600fdc0865f4b0ee05a17b858f2 |
Thank @Lightning228 , I do appreciate that. I think you can listen mouse move/click event and use this event to generate a new(modified) image and replace it by self.imageLabel.setPixmap(QPixmap.fromImage(your_new_image))
There's a example of mouse event listening but verticalScrollBar https://gist.github.com/acbetter/e7d0c600fdc0865f4b0ee05a17b858f2
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Hello @acbetter . Very good code, great job, keep up the good work! I'm using part of your code and I have a problem that I can't solve. I want to create a vertical line in this place by clicking the mouse on an image (pixmap) (as I understand it, I need to work with Qpainter), but for reasons unknown to me I can’t do this. If you were able to make such a large application, I think you might have some ideas about it. Thank you very much in advance!