PyQt5 Tutorial #15 – Creating Multiple Windows

In this tutorial, we will learn how to create multiple windows in a PyQt5 application. Creating multiple windows in a PyQt5 application can be useful when you want to organize your application into different sections or allow the user to perform different tasks in separate windows.

To create multiple windows in a PyQt5 application, we will use the QMainWindow class to create the main window, and then instantiate additional windows as needed.

Creating the Main Window

First, we will create the main window using the following code:

		
from PyQt5.QtWidgets import QApplication, QMainWindow

app = QApplication([])
main_window = QMainWindow()
main_window.show()
app.exec_()
		
	

When you run this code, the main window will appear on the screen.

Creating Additional Windows

To create additional windows in a PyQt5 application, we can use the QDialog class. This class represents a popup or modal window that can be used to display additional information or get input from the user.

Here is an example of how to create an additional window using the QDialog class:

		
from PyQt5.QtWidgets import QDialog

additional_window = QDialog()
additional_window.show()
		
	

When you run this code, an additional window will appear on the screen as a modal dialog.

Connecting Multiple Windows

Once we have created multiple windows in a PyQt5 application, we may want to connect them together in some way. For example, we may want to pass data from one window to another, or update the main window based on actions taken in an additional window.

To connect multiple windows in a PyQt5 application, we can use signals and slots. Signals are emitted when a particular event occurs, and slots are functions that are called in response to a signal. By connecting the signals from one window to the slots of another, we can establish communication between the different windows in our application.

Here is an example of how to connect the accepted signal of a dialog to a slot in the main window:

		
additional_window.accepted.connect(main_window.update_data)
		
	

In this example, when the user accepts the changes in the additional window, the update_data function in the main window will be called to update the displayed data.

Conclusion

Creating multiple windows in a PyQt5 application can help to organize and enhance the user experience. By using the QMainWindow and QDialog classes, and connecting the different windows using signals and slots, we can create a more dynamic and interactive application.