How to install PyQt5 and QT Designer on Raspberry pi 4
Introduction:
Raspberry Pi is a popular and versatile platform that can be used for a wide range of applications, from home automation to robotics to media centers. One of the key strengths of Raspberry Pi is its ability to run a variety of software tools, including Qt and PyQt, which enable developers to create powerful and interactive user interfaces. In this article, we will explore how to install PyQt5 and Qt Designer on Raspberry Pi 4, and provide some basic and advanced examples to demonstrate how to use these tools effectively.
First, we will cover the installation process step by step, starting with the installation of PyQt5, which is a Python binding for Qt. We will then show you how to install Qt Designer, which is a powerful tool for designing and prototyping user interfaces. After that, we will dive into some basic examples of how to use Qt Designer to create simple UIs to display time. From there, we will move on to more advanced examples.
Pyqt5 Installation on Raspberry pi 4:
Update and upgrade your Raspberry Pi Before installing any new software on your Raspberry Pi, it’s important to make sure you have the latest updates and upgrades installed. You can do this by running the following commands in the terminal:
|
1 |
sudo apt-get update |
|
1 |
sudo apt-get upgrade |
Install the required dependencies To install PyQt5 on Raspberry Pi 4, you need to install some dependencies first. Run the following command in the terminal:
|
1 |
sudo apt-get install python3-pyqt5 pyqt5-dev-tools |
This will install the Python 3 version of PyQt5 and the development tools required to build PyQt5 applications.
Test the installation whether PyQt5 is installed correctly, you can run a simple example script. Open a new Python file in your text editor of choice and paste in the following code:
|
1 2 3 4 5 6 7 |
import sys from PyQt5.QtWidgets import QApplication, QLabel app = QApplication(sys.argv) label = QLabel("Hello, World!") label.show() sys.exit(app.exec_()) |
Save the file as pyqt5Test.py and then run it in the terminal:
python3 pyqt5Test.py
or press the play button if you are using any programming ide in my case I am using Mu ide
This should launch a window displaying the text “Hello, World!”.
Congratulations! You’ve successfully installed PyQt5 on your Raspberry Pi 4 and tested it with a simple example script. Now you can start building your own PyQt5 applications on your Raspberry Pi.
How to make Digital Clock in pyqt5 using Raspberry pi 4:
A digital clock is a simple yet useful application that can be easily built using Python and PyQt5 on a Raspberry Pi 4. PyQt5 is a powerful GUI toolkit for Python that allows you to create desktop applications with rich graphical user interfaces. With its extensive set of widgets and layouts, PyQt5 makes it easy to create custom GUI components and layouts for your applications.
In this example, we will guide you through the process of building a digital clock using PyQt5 on a Raspberry Pi 4.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 |
import sys from PyQt5.QtWidgets import QApplication, QWidget from PyQt5.QtWidgets import QVBoxLayout, QLabel from PyQt5.QtGui import QFont from PyQt5.QtCore import QTimer, QTime, Qt class Window(QWidget): def __init__(self): super().__init__() # main window self.setGeometry(100, 100, 800, 400) # vertical layout /display layout = QVBoxLayout() #fonts fonts = QFont('Arial', 120, QFont.Bold) fonts2= QFont('Arial', 50, QFont.Bold) # label object self.label = QLabel() # alignment of the label to centre self.label.setAlignment(Qt.AlignCenter) # display fonts self.label.setFont(fonts) self.label_text = QLabel("Programming Digest") self.label_text.setAlignment(Qt.AlignCenter) self.label_text.setFont(fonts2) layout.addWidget(self.label_text) # add label on layout layout.addWidget(self.label) self.setLayout(layout) # timer clock object timerClock = QTimer(self) timerClock.timeout.connect(self.displayTime) # updating the timer timerClock.start(1000) def displayTime(self): # get current time present_time = QTime.currentTime() # QTime object into a string time_label = present_time.toString('hh:mm:ss') # display time self.label.setText(time_label) Base = QApplication(sys.argv) # Window instance window = Window() window.show() App.exit(Base.exec_()) |
Code Explanation:
|
1 2 3 4 5 |
import sys from PyQt5.QtWidgets import QApplication, QWidget from PyQt5.QtWidgets import QVBoxLayout, QLabel from PyQt5.QtGui import QFont from PyQt5.QtCore import QTimer, QTime, Qt |
This section imports the necessary modules for building the digital clock application. We import the QApplication, QWidget, QVBoxLayout, QLabel, QFont, QTimer, QTime, and Qt classes from PyQt5 library.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 |
class Window(QWidget): def __init__(self): super().__init__() self.setGeometry(100, 100, 800, 400) layout = QVBoxLayout() fonts = QFont('Arial', 120, QFont.Bold) fonts2= QFont('Arial', 50, QFont.Bold) self.label = QLabel() self.label.setAlignment(Qt.AlignCenter) self.label.setFont(fonts) self.label_text = QLabel("Programming Digest") self.label_text.setAlignment(Qt.AlignCenter) self.label_text.setFont(fonts2) layout.addWidget(self.label_text) layout.addWidget(self.label) self.setLayout(layout) timerClock = QTimer(self) timerClock.timeout.connect(self.displayTime) timerClock.start(1000) |
This is the main class Window of our application. In this class, we define the layout and design of our digital clock. We create two labels for displaying text, one is the main label for displaying time and the other is for the application title. We set the alignment and font of the labels and add them to a vertical layout layout that we create. We then set the layout to the window by calling setLayout(). We create a timer object timerClock which updates the display after every second by calling the displayTime() function.
|
1 2 3 4 5 6 7 |
def displayTime(self): present_time = QTime.currentTime() time_label = present_time.toString('hh:mm:ss') self.label.setText(time_label) |
This function displayTime() is called every time the timer object updates, it retrieves the present time using QTime.currentTime() and formats it into a string with the desired format using toString(). Finally, it sets the formatted time string to the main label self.label by calling setText().
|
1 2 3 4 5 6 7 |
Base = QApplication(sys.argv) window = Window() window.show() App.exit(Base.exec_()) |
This last section creates an instance of the QApplication class, Base, which handles the application’s event loop. It creates an instance of the Window class and shows it using show(). Finally, it runs the event loop using Base.exec_() to start the application.
Practical Demonstration:
Qt Creator and Qt Designer in Raspberry pi 4 for pyqt5:
Qt Designer is a powerful GUI design tool that allows developers to easily create graphical user interfaces (GUIs) for their applications. With the increasing popularity of Raspberry Pi as a platform for embedded systems development, many developers are looking for ways to use Qt Designer for their PyQt5 projects on this platform. In this section, we will provide a detailed guide on how to install Qt Designer on a Raspberry Pi and configure it for use with PyQt5. We will walk you through the steps of installing the necessary dependencies, setting up the development environment, and launching Qt Designer on your Raspberry Pi. By the end of this article, you will have a fully functional Qt Designer installation on your Raspberry Pi, ready to create beautiful and functional GUIs for your embedded systems projects with PyQt5.
Install Qt Designer and Qt Creator on Raspberry pi 4:
You can install Qt Designer on your Raspberry Pi 4 by following these steps:
Open a terminal window on your Raspberry Pi 4.
Install the Qt Designer package by running the following command:
|
1 |
sudo apt-get install qtcreator |
Type y and press enter to install the QT creator and QT designer
This will install Qt Designer and other Qt tools that you may find useful.
As you can see our Qt Creator and Qt Designer is installed
Now test a simple GUI Design.
how to make Digital Clock using PyQt5 and Qt Designer in Raspberry pi 4:
You can display the current time on a QLabel widget in Qt Designer using Raspberry Pi 4 by following these steps:
Open Qt Designer and create a new form.
Select dialog without buttons and press the create button
Drag and drop a QLabel widget onto the form.
In the Property Editor, set the label’s text property as per your requirement:
Select the lable name for programming, in my case i select lbTime.
Save the form with .ui extension in the folder where the main code is saved.
Now open the main.py file in Ide and paste the below code
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 |
import sys from PyQt5.QtCore import QTimer, QTime from PyQt5.QtWidgets import QApplication, QDialog from PyQt5.uic import loadUi class DisplayTime(QDialog): def __init__(self): super(DisplayTime, self).__init__() loadUi('Gui.ui', self) self.setWindowTitle('Display Time') self.update_time() self.timer = QTimer() self.timer.timeout.connect(self.update_time) self.timer.start(1000) def update_time(self): current_time = QTime.currentTime() time_label = current_time.toString('hh:mm:ss') self.lbTime.setText(time_label) app = QApplication(sys.argv) widget = DisplayTime() widget.show() sys.exit(app.exec_()) |
Code Explanation:
|
1 2 3 4 |
import sys from PyQt5.QtCore import QTimer, QTime from PyQt5.QtWidgets import QApplication, QDialog from PyQt5.uic import loadUi |
These import statements bring in the required classes from PyQt5, including QTimer, QTime, QApplication, QDialog, and loadUi.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
class DisplayTime(QDialog): def __init__(self): super(DisplayTime, self).__init__() loadUi('Gui.ui', self) self.setWindowTitle('Display Time') self.update_time() self.timer = QTimer() self.timer.timeout.connect(self.update_time) self.timer.start(1000) def update_time(self): current_time = QTime.currentTime() time_label = current_time.toString('hh:mm:ss') self.lbTime.setText(time_label) |
This defines a class called DisplayTime that inherits from QDialog. The __init__ method loads a UI file called Gui.ui using the loadUi method, sets the window title to “Display Time”, and sets up a QTimer to call the update_time method every second.
The update_time method retrieves the current time using QTime.currentTime(), formats it as a string with the format ‘hh:mm:ss’, and sets the text of a QLabel object named lbTime to the formatted time string.
|
1 2 3 4 |
app = QApplication(sys.argv) widget = DisplayTime() widget.show() sys.exit(app.exec_()) |
This creates a QApplication object with the command line arguments sys.argv, creates an instance of the DisplayTime class, shows the widget, and starts the event loop with app.exec_(). The lbTime label will update every second to display the current time.
Practical Demonstration:
Now make some changes in qt designer and just save the gui file
Now run again
What is QT5 Assistant?
Qt5 Assistant is a tool that comes with the Qt software development framework, which is a popular cross-platform application development framework used to build desktop and mobile applications. Qt5 Assistant is a help browser that provides developers with easy access to the Qt documentation.
Here are some features of Qt5 Assistant:
- Documentation Browser: Qt5 Assistant provides developers with access to the Qt documentation in a user-friendly interface that allows them to search, browse and read documentation offline. The documentation includes API reference, tutorials, examples, and other helpful resources.
- Search Functionality: Qt5 Assistant includes a search function that allows developers to search for specific keywords, classes or methods. The search results can be filtered based on the type of content or location within the documentation.
- Bookmarking: Developers can bookmark specific sections of the documentation for easy reference later on.
- Example Browser: Qt5 Assistant includes a built-in example browser that allows developers to search for and view Qt code examples. The examples are organized by category and provide a helpful starting point for developing with Qt.
- Tool Tips: Qt5 Assistant provides developers with tool tips that pop up when hovering over a Qt class, method or property. The tool tips include a brief description of the item and links to related documentation.
- Integration with Qt Creator: Qt5 Assistant is integrated with Qt Creator, the official IDE for developing with Qt. Developers can easily access Qt5 Assistant from within Qt Creator and use it to search for documentation and examples while coding.
- Cross-Platform: QT5 Assistant is cross-platform, which means it can be used on multiple operating systems, including Raspberry Pi 4. This makes it a valuable tool for developers working on cross-platform applications.
In summary, Qt5 Assistant is a valuable tool for developers using the Qt framework. It provides easy access to documentation, examples, and other helpful resources, making it easier to learn and develop with Qt.
What is Qt linguist?
Qt Linguist is a tool provided by the Qt framework for creating and managing translations of Qt-based applications. It is used to translate text strings in source code into various languages, allowing developers to create multilingual applications.
Here are some features of Qt Linguist:
- Translation Support: Qt Linguist provides a user-friendly interface for managing translations of Qt-based applications. Developers can use it to translate strings in the source code into different languages.
- Translation Memory: Qt Linguist has a translation memory feature that saves previous translations for later use. This can save time when translating similar strings in the future.
- Visual Context: Qt Linguist provides visual context for the strings being translated, allowing translators to see how the strings will be used in the application.
- Integration with Qt Creator: Qt Linguist is integrated with Qt Creator, the official IDE for developing with Qt. Developers can easily access Qt Linguist from within Qt Creator and use it to manage translations.
- Multi-Platform Support: Qt Linguist is a cross-platform tool, which means it can be used on multiple operating systems, including Raspberry Pi 4.
In summary, Qt Linguist is a valuable tool for developers who need to translate Qt-based applications into different languages. It provides a user-friendly interface, translation memory, visual context, integration with Qt Creator, and multi-platform support.
What is Qt Creator?
Qt Creator is an Integrated Development Environment (IDE) for developing applications using the Qt framework. It is designed to provide developers with a comprehensive set of tools to create cross-platform applications for desktop, mobile, and embedded devices.
Here are some features of Qt Creator:
- Code Editor: Qt Creator provides a powerful code editor with features like syntax highlighting, auto-completion, and code navigation.
- Project Management: Qt Creator allows developers to manage their projects with ease. It provides project templates, build settings, and version control integration.
- Debugging: Qt Creator has a built-in debugger that allows developers to debug their applications on the fly. It provides features like breakpoints, variable inspection, and call stack navigation.
- Design Tools: Qt Creator has a drag-and-drop interface designer, making it easy for developers to create user interfaces. It also has a resource editor for managing images, icons, and other resources.
- Multi-platform Support: Qt Creator is a cross-platform tool that can be used on multiple operating systems, including Raspberry Pi.
- Integrated Tools: Qt Creator integrates seamlessly with other tools in the Qt ecosystem, such as Qt Designer, Qt Linguist, and Qt Assistant.
In summary, Qt Creator is a powerful IDE for developing cross-platform applications using the Qt framework. It provides a comprehensive set of tools for code editing, project management, debugging, design, and integration with other Qt tools. As a Raspberry Pi user, Qt Creator can help you create applications that run on your Raspberry Pi and other platforms.
