PyQT open files to edit

In this PyQT application development tutorial, we're going to cover how to open files in our GUI.

What good is a text editor, if we have no text to edit? Luckily for us, PyQT handles file operations like this that are common in applications very well. Here's how we might open a file, and populate our text field with the contents.

First we create the option:

        openFile = QtGui.QAction("&Open File", self)
        openFile.setShortcut("Ctrl+O")
        openFile.setStatusTip('Open File')
        openFile.triggered.connect(self.file_open)
		

Then we add this option to our fileMenu:

        fileMenu.addAction(file_open)

Now we actually open the file and populate our editor:

    def file_open(self):
        name = QtGui.QFileDialog.getOpenFileName(self, 'Open File')
        file = open(name,'r')

        self.editor()

        with file:
            text = file.read()
            self.textEdit.setText(text)

The full code is now:

import sys
from PyQt4 import QtGui, QtCore

class Window(QtGui.QMainWindow):

    def __init__(self):
        super(Window, self).__init__()
        self.setGeometry(50, 50, 500, 300)
        self.setWindowTitle("PyQT tuts!")
        self.setWindowIcon(QtGui.QIcon('pythonlogo.png'))

        extractAction = QtGui.QAction("&GET TO THE CHOPPAH!!!", self)
        extractAction.setShortcut("Ctrl+Q")
        extractAction.setStatusTip('Leave The App')
        extractAction.triggered.connect(self.close_application)

        openEditor = QtGui.QAction("&Editor", self)
        openEditor.setShortcut("Ctrl+E")
        openEditor.setStatusTip('Open Editor')
        openEditor.triggered.connect(self.editor)

        openFile = QtGui.QAction("&Open File", self)
        openFile.setShortcut("Ctrl+O")
        openFile.setStatusTip('Open File')
        openFile.triggered.connect(self.file_open)

        self.statusBar()

        mainMenu = self.menuBar()
        
        fileMenu = mainMenu.addMenu('&File')
        fileMenu.addAction(extractAction)
        fileMenu.addAction(openFile)
        
        editorMenu = mainMenu.addMenu("&Editor")
        editorMenu.addAction(openEditor)

        self.home()

    def home(self):
        btn = QtGui.QPushButton("Quit", self)
        btn.clicked.connect(self.close_application)
        btn.resize(btn.minimumSizeHint())
        btn.move(0,100)

        extractAction = QtGui.QAction(QtGui.QIcon('todachoppa.png'), 'Flee the Scene', self)
        extractAction.triggered.connect(self.close_application)
        self.toolBar = self.addToolBar("Extraction")
        self.toolBar.addAction(extractAction)

        fontChoice = QtGui.QAction('Font', self)
        fontChoice.triggered.connect(self.font_choice)
        #self.toolBar = self.addToolBar("Font")
        self.toolBar.addAction(fontChoice)

        color = QtGui.QColor(0, 0, 0)

        fontColor = QtGui.QAction('Font bg Color', self)
        fontColor.triggered.connect(self.color_picker)

        self.toolBar.addAction(fontColor)

        checkBox = QtGui.QCheckBox('Enlarge Window', self)
        checkBox.move(300, 25)
        checkBox.stateChanged.connect(self.enlarge_window)

        self.progress = QtGui.QProgressBar(self)
        self.progress.setGeometry(200, 80, 250, 20)

        self.btn = QtGui.QPushButton("Download",self)
        self.btn.move(200,120)
        self.btn.clicked.connect(self.download)

        #print(self.style().objectName())
        self.styleChoice = QtGui.QLabel("Windows Vista", self)

        comboBox = QtGui.QComboBox(self)
        comboBox.addItem("motif")
        comboBox.addItem("Windows")
        comboBox.addItem("cde")
        comboBox.addItem("Plastique")
        comboBox.addItem("Cleanlooks")
        comboBox.addItem("windowsvista")

        comboBox.move(50, 250)
        self.styleChoice.move(50,150)
        comboBox.activated[str].connect(self.style_choice)

        cal = QtGui.QCalendarWidget(self)
        cal.move(500,200)
        cal.resize(200,200)

        self.show()

    def file_open(self):
        name = QtGui.QFileDialog.getOpenFileName(self, 'Open File')
        file = open(name,'r')

        self.editor()

        with file:
            text = file.read()
            self.textEdit.setText(text)

    def color_picker(self):
        color = QtGui.QColorDialog.getColor()
        self.styleChoice.setStyleSheet("QWidget { background-color: %s}" % color.name())

    def editor(self):
        self.textEdit = QtGui.QTextEdit()
        self.setCentralWidget(self.textEdit)


    def font_choice(self):
        font, valid = QtGui.QFontDialog.getFont()
        if valid:
            self.styleChoice.setFont(font)

    def style_choice(self, text):
        self.styleChoice.setText(text)
        QtGui.QApplication.setStyle(QtGui.QStyleFactory.create(text))

    def download(self):
        self.completed = 0

        while self.completed < 100:
            self.completed += 0.0001
            self.progress.setValue(self.completed)  

    def enlarge_window(self, state):
        if state == QtCore.Qt.Checked:
            self.setGeometry(50,50, 1000, 600)
        else:
            self.setGeometry(50, 50, 500, 300)
        

    def close_application(self):
        choice = QtGui.QMessageBox.question(self, 'Extract!',
                                            "Get into the chopper?",
                                            QtGui.QMessageBox.Yes | QtGui.QMessageBox.No)
        if choice == QtGui.QMessageBox.Yes:
            print("Extracting Naaaaaaoooww!!!!")
            sys.exit()
        else:
            pass
        
        

    
def run():
    app = QtGui.QApplication(sys.argv)
    GUI = Window()
    sys.exit(app.exec_())


run()     

The result:

Finally, in the next tutorial, we'll cover actually saving the file after we have edited it.

The next tutorial: PyQT file saving