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Menus and toolbars in PyQt5
In this part of the PyQt5 tutorial, we create create statusbar, menubar and a toolbar. A menu is a group of commands located in a menubar. A toolbar has buttons with some common commands in the application. Statusbar shows status information, usually at the bottom of the application window.
QMainWindow
The QMainWindow class provides a main application window. This enables to create a classic application skeleton with a statusbar, toolbars, and a menubar.
Statusbar
A statusbar is a widget that is used for displaying status information.
statusbar.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a statusbar.
Author: Jan Bodnar Website: zetcode.com Last edited: August 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, QApplication
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.statusBar().showMessage('Ready')
self.setGeometry(300, 300, 250, 150)
self.setWindowTitle('Statusbar')
self.show()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
The statusbar is created with the help of the QMainWindow widget.
self.statusBar().showMessage('Ready') To get the statusbar, we call the statusBar() method of the QtGui.QMainWindow class. The first call of the method creates a status bar. Subsequent calls return the statusbar object. The showMessage() displays a message on the statusbar.
Simple menu
A menubar is a common part of a GUI application. It is a group of commands located in various menus. (Mac OS treats menubars differently. To get a similar outcome, we can add the following line: menubar.setNativeMenuBar(False).)
simplemenu.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a menubar. The menubar has one menu with an exit action.
Author: Jan Bodnar Website: zetcode.com Last edited: January 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, QAction, qApp, QApplication from PyQt5.QtGui import QIcon
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
exitAct = QAction(QIcon('exit.png'), '&Exit', self)
exitAct.setShortcut('Ctrl+Q')
exitAct.setStatusTip('Exit application')
exitAct.triggered.connect(qApp.quit)
self.statusBar()
menubar = self.menuBar()
fileMenu = menubar.addMenu('&File')
fileMenu.addAction(exitAct)
self.setGeometry(300, 300, 300, 200)
self.setWindowTitle('Simple menu')
self.show()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
In the above example, we create a menubar with one menu. This menu will contain one action which will terminate the application if selected. A statusbar is created as well. The action is accessible with the Ctrl+Q shortcut.
exitAct = QAction(QIcon('exit.png'), '&Exit', self)
exitAct.setShortcut('Ctrl+Q')
exitAct.setStatusTip('Exit application')
QAction is an abstraction for actions performed with a menubar, toolbar, or with a custom keyboard shortcut. In the above three lines, we create an action with a specific icon and an 'Exit' label. Furthermore, a shortcut is defined for this action. The third line creates a status tip which is shown in the statusbar when we hover a mouse pointer over the menu item.
exitAct.triggered.connect(qApp.quit) When we select this particular action, a triggered signal is emitted. The signal is connected to the quit() method of the QApplication widget. This terminates the application.
menubar = self.menuBar() fileMenu = menubar.addMenu('&File') fileMenu.addAction(exitAction) The menuBar() method creates a menubar. We create a file menu with addMenu() and add the action with addAction().
Submenu
A submenu is a menu located inside another menu.
submenu.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a submenu.
Author: Jan Bodnar Website: zetcode.com Last edited: August 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, QAction, QMenu, QApplication
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
menubar = self.menuBar()
fileMenu = menubar.addMenu('File')
impMenu = QMenu('Import', self)
impAct = QAction('Import mail', self)
impMenu.addAction(impAct)
newAct = QAction('New', self)
fileMenu.addAction(newAct)
fileMenu.addMenu(impMenu)
self.setGeometry(300, 300, 300, 200)
self.setWindowTitle('Submenu')
self.show()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
In the example, we have two menu items; one is located in the File menu and the other one in the File's Import submenu.
impMenu = QMenu('Import', self) New menu is created with QMenu.
impAct = QAction('Import mail', self) impMenu.addAction(impAct) An action is added to the submenu with addAction().
Submenu Figure: Submenu Check menu
In the following example, we create a menu that can be checked and unchecked.
checkmenu.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a checkable menu.
Author: Jan Bodnar Website: zetcode.com Last edited: August 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, QAction, QApplication
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.statusbar = self.statusBar()
self.statusbar.showMessage('Ready')
menubar = self.menuBar()
viewMenu = menubar.addMenu('View')
viewStatAct = QAction('View statusbar', self, checkable=True)
viewStatAct.setStatusTip('View statusbar')
viewStatAct.setChecked(True)
viewStatAct.triggered.connect(self.toggleMenu)
viewMenu.addAction(viewStatAct)
self.setGeometry(300, 300, 300, 200)
self.setWindowTitle('Check menu')
self.show()
def toggleMenu(self, state):
if state:
self.statusbar.show()
else:
self.statusbar.hide()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
The code example creates a View menu with one action. The action shows or hides a statusbar. When the statusbar is visible, the menu item is checked.
viewStatAct = QAction('View statusbar', self, checkable=True) With the checkable option we create a checkable menu.
viewStatAct.setChecked(True) Since the statusbar is visible from the start, we check the action with setChecked() method.
def toggleMenu(self, state):
if state:
self.statusbar.show()
else:
self.statusbar.hide()
Depending on the state of the action, we show or hide the statusbar.
Check menu Figure: Check menu Context menu
A context menu, also called a popup menu, is a list of commands that appears under some context. For example, in a Opera web browser when we right click on a web page, we get a context menu. Here we can reload a page, go back, or view a page source. If we right click on a toolbar, we get another context menu for managing toolbars.
contextmenu.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a context menu.
Author: Jan Bodnar Website: zetcode.com Last edited: August 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, qApp, QMenu, QApplication
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.setGeometry(300, 300, 300, 200)
self.setWindowTitle('Context menu')
self.show()
def contextMenuEvent(self, event):
cmenu = QMenu(self)
newAct = cmenu.addAction("New")
opnAct = cmenu.addAction("Open")
quitAct = cmenu.addAction("Quit")
action = cmenu.exec_(self.mapToGlobal(event.pos()))
if action == quitAct:
qApp.quit()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
To work with a context menu, we have to reimplement the contextMenuEvent() method.
action = cmenu.exec_(self.mapToGlobal(event.pos())) The context menu is displayed with the exec_() method. The get the coordinates of the mouse pointer from the event object. The mapToGlobal() method translates the widget coordinates to the global screen coordinates.
if action == quitAct: qApp.quit() If the action returned from the context menu equals to quit action, we terminate the application.
Toolbar
Menus group all commands that we can use in an application. Toolbars provide a quick access to the most frequently used commands.
toolbar.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a toolbar. The toolbar has one action, which terminates the application, if triggered.
Author: Jan Bodnar Website: zetcode.com Last edited: August 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, QAction, qApp, QApplication from PyQt5.QtGui import QIcon
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
exitAct = QAction(QIcon('exit24.png'), 'Exit', self)
exitAct.setShortcut('Ctrl+Q')
exitAct.triggered.connect(qApp.quit)
self.toolbar = self.addToolBar('Exit')
self.toolbar.addAction(exitAct)
self.setGeometry(300, 300, 300, 200)
self.setWindowTitle('Toolbar')
self.show()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
In the above example, we create a simple toolbar. The toolbar has one tool action, an exit action which terminates the application when triggered.
exitAct = QAction(QIcon('exit24.png'), 'Exit', self) exitAct.setShortcut('Ctrl+Q') exitAct.triggered.connect(qApp.quit) Similar to the menubar example above, we create an action object. The object has a label, icon, and a shorcut. A quit() method of the QtGui.QMainWindow is connected to the triggered signal.
self.toolbar = self.addToolBar('Exit') self.toolbar.addAction(exitAction) The toolbar is created with the addToolBar() method. We add an action object to the toolbar with addAction().
Toolbar Figure: Toolbar Putting it together
In the last example of this section, we will create a menubar, toolbar, and a statusbar. We will also create a central widget.
mainwindow.py #!/usr/bin/python3
-- coding: utf-8 --
""" ZetCode PyQt5 tutorial
This program creates a skeleton of a classic GUI application with a menubar, toolbar, statusbar, and a central widget.
Author: Jan Bodnar Website: zetcode.com Last edited: August 2017 """
import sys from PyQt5.QtWidgets import QMainWindow, QTextEdit, QAction, QApplication from PyQt5.QtGui import QIcon
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
textEdit = QTextEdit()
self.setCentralWidget(textEdit)
exitAct = QAction(QIcon('exit24.png'), 'Exit', self)
exitAct.setShortcut('Ctrl+Q')
exitAct.setStatusTip('Exit application')
exitAct.triggered.connect(self.close)
self.statusBar()
menubar = self.menuBar()
fileMenu = menubar.addMenu('&File')
fileMenu.addAction(exitAct)
toolbar = self.addToolBar('Exit')
toolbar.addAction(exitAct)
self.setGeometry(300, 300, 350, 250)
self.setWindowTitle('Main window')
self.show()
if name == 'main':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
This code example creates a skeleton of a classic GUI application with a menubar, toolbar, and a statusbar.
textEdit = QTextEdit() self.setCentralWidget(textEdit) Here we create a text edit widget. We set it to be the central widget of the QMainWindow. The central widget will occupy all space that is left.
Main window Figure: Main window In this part of the PyQt5 tutorial, we worked with menus, toolbars, a statusbar, and a main application window.