If you like a style, but want to change its colors (eg. The available styles depend on your platform but are usually 'Fusion', 'Windows', 'WindowsVista' (Windows only) and 'Macintosh' (Mac only). If you use the Windows style instead, then it looks as follows: The coarsest way to change the appearance of your application is to set the global Style. There are many mechanisms that let you customize the look and feel of your application. One of Qt's strengths is its support for custom styles. There are of course many other kinds of layouts (eg. As in our first application, we end with calls to. Finally, we tell the window to use this layout (and thus its contents). Next, we create the layout and add two QPushButtons to it. We use the most basic type QWidget for it because it merely acts as a container and we don't want it to have any special behavior.
The code for this screenshot is: Pyqt Simple Menu App Windows And Mac FreeĪs before, we instantiate a QApplication. For instance, you can use QVBoxLayout to stack widgets vertically:
In this case, you need to tell Qt how to position them. Like the example above, your GUI will most likely consist of multiple widgets. You can download the code for the app shown in the screenshot here, if you are interested. The following screenshot shows the most common Qt widgets: For example, a window can contain a button, which in turn contains a label. Like HTML elements, widgets are often nested. WidgetsĮverything you see in a (Py)Qt app is a widget: Buttons, labels, windows, dialogs, progress bars etc. If all this worked as expected then well done! You've just built your first GUI app with Python and Qt. The last step is to hand control over to Qt and ask it to 'run the application until the user closes it'. Then, we tell Qt to show the label on the screen:ĭepending on your operating system, this already opens a tiny little window: Now, to actually see something, we create a simple label: Because our app doesn't use any parameters, we leave the brackets empty. The brackets in the above line represent the command line arguments passed to the application. You will therefore need it in virtually every (Py)Qt app you write. Many parts of Qt don't work until you have executed the above line. This is a requirement of Qt: Every GUI app must have exactly one instance of QApplication. Next, we create a QApplication with the command: We will execute the following commands:įirst, we tell Python to load PyQt via the import statement: Time to write our very first GUI app! With the virtual environment still active, start Python.
To now install PyQt, issue the following command:Ĭongratulations! You've successfully set up PyQt5. You can see that the virtual environment is active by the (venv) prefix in your shell: To activate the virtual environment on Windows, run: To create a virtual environment in the current directory, execute the following command: This is unlike a system-wide installation of those libraries, which would affect all of your other projects as well.
A virtual environment is simply a local directory that contains the libraries for a specific project. The best way to manage dependencies in Python is via a virtual environment.
Since the APIs are so similar, you can easily switch your apps to Qt for Python later. We use PyQt here because it is more mature. It's backed by the Qt company, and thus likely the future.
Unlike PyQt, it is licensed under the LGPL and can thus be used for free in commercial projects. You may still find the occasional mention of (Py)Qt4 on the web, but it is old and no longer supported.Īn interesting new competitor to PyQt is Qt for Python. PyQt5 refers to the most recent version 5 of Qt. By using it from Python, you can build applications much more quickly while not sacrificing much of the speed of C++. PyQt is a library that lets you use the Qt GUI framework from Python. It even covers creating an installer for your app. This PyQt5 tutorial shows how to use Python 3 and Qt to create a GUI on Windows, Mac or Linux. To get a similar outcome, we can add the following line: tNativeMenuBar(False).). It is a group of commands located in various menus. A menubar is a common part of a GUI application. The app has a few simple features like support for receiving images via drag-and-drop, and it can proportionally resize them before.
How-to: Deploying PyQt applications on Windows and Mac OS X. Pyqt Simple Menu App Windows And Mac Os.Pyqt Simple Menu App Windows And Mac Free.