PyQt5 Notes

Installation

Install PyQt5 package with:

python -m pip install pyqt5

Install the designer from https://www.qt.io/download-qt-installer

Convert a designer file to Python file

pyuic5 templates/main_window.ui -o main_window.py

Threading

Use QThreads.

Create a class and subclass QThread.

Create a signal(channel) using pyqtSignal and specify what it should expect:

done_signal = pyqtSignal(str)

Tie the done signal to a function in the calling object

thread.done_signal.connect(func_name)

And then in the QThread class call emit:

self.done_signal.emit(output_value)

If the thread is called in a short-lived function, store the thread in an object or somewhere where it won't get garbage collected before it finishes running.

Packaging

Use PyInstaller to create standalone packages.

python -m pip install pyinstaller
pyinstall myapp.py

Dialogs

There are a few dialog options:

QInputDialog.get{Int,Double,Item,Text}()
QColorDialog
QFileDialog
QFontDialog
QInputDialog
QMessageBox.{question,etc}()
QWizard
QErrorMessage

SysTray

• https://evileg.com/en/post/68/
• https://www.youtube.com/watch?v=1_4jfqYOi6w

Create a QSystemTrayIcon, then call set_icon() on it and then show().

Create a QMenu, call addAction to add QActions that have been created and connected to a callback using action.triggered.connect(func_name). Then attach the QMenu to the QSystemTrayIcon using tray_icon.setContextMenu(menu).

You can display balloon alerts from the tray icon using tray_icon.showMessage() and passing a value like QSystemTrayIcon.Information.

References

https://github.com/DevDungeon/PyQt5-Bitcoin-Price-Checker DevDungeon/PyQt5-Bitcoin-Price-Checker#1

Building for Android: https://medium.com/@Lola_Dam/packaging-pyqt-application-using-pyqtdeploy-for-both-linux-and-android-32ac7824708b