**Qt for Mobile Development: Creating a Mobile Photo Editor with Qt Quick and PySide6** In this article, we will explore how to create a mobile photo editor application using Qt Quick and PySide6. This app will have features like image loading, zooming, filtering, and saving. **Prerequisites:** * PySide6 installed on your system (https://www.riverbankcomputing.com/software/pyside/) * Qt Design Studio for designing Qt Quick UI (https://www.qt.io/qt-design-studio) * A mobile device or emulator for testing **Setting Up the Project** Create a new PySide6 project using Qt Creator or your favorite IDE. Make sure to select Qt Quick Application as the project template. **Designing the UI** We will use Qt Quick to design our UI. Here is a simple UI that includes buttons for loading, zooming, and applying filters to the image. ```qml import QtQuick 2.12 import QtQuick.Controls 2.12 import QtQuick.Layouts 1.12 ApplicationWindow { id: root visible: true width: 400 height: 600 ColumnLayout { id: layout anchors.fill: parent Button { id: loadButton text: "Load Image" onClicked: { fileDialog.open() } } Rectangle { id: imageContainer Layout.fillWidth: true Layout.fillHeight: true border.color: "black" Image { id: imageView anchors.fill: parent source: "" asynchronous: true onStatusChanged: { if (status === Image.Ready) { console.log("Image loaded successfully.") } else if (status === Image.Error) { console.log("Error loading image.") } } } } Button { id: zoomButton text: "Zoom" onClicked: { imageView.scale += 0.1 } } Button { id: filterButton text: "Apply Filter" onClicked: { // Apply a filter to the image } } FileDialog { id: fileDialog visible: false title: "Select an image" nameFilters: ["Image files (*.png *.jpg *.jpeg)"] onAccepted: { imageView.source = fileUrl } } } } ``` **Loading and Displaying the Image** We will use the PyQt6 `QGuiApplication` to display the image. Here is the Python code that loads the image: ```python import sys from PySide6 import QtWidgets, QtGui, QtCore import qml_py6 def main(): app = QtWidgets.QApplication(sys.argv) qmlWindow = qml_py6.Qt_QmlAppWindow('qml/image_editor.qml') engine = qmlWindow.qmlEngine imageLoader = qml_py6.Qt_QmlImageLoader() engine.rootContext().setContextProperty("imageLoader", imageLoader) qmlWindow.show() sys.exit(app.exec()) if __name__ == '__main__': main() ``` **Applying a Filter to the Image** We will use the OpenCV library to apply a filter to the image. Here is the Python code that applies a filter: ```python import cv2 from PySide6 import QtCore import qml_py6 class Qt_QmlImageLoader(QtCore.QObject): def __init__(self): super(Qt_QmlImageLoader, self).__init__() @QtCore.Slot(str, result=str) def apply_filter(self, image_path): img = cv2.imread(image_path) if img is not None: gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) blurred = cv2.GaussianBlur(gray, (5, 5), 0) threshold = cv2.threshold(blurred, 80, 255, cv2.THRESH_BINARY)[1] cv2.imwrite("filtered_image.png", threshold) return "filtered_image.png" else: return "" ``` **Compiling and Running the App** Compile the app using the following command: ```bash pyside6-uic image_editor.qml -o image_editor.ui ``` Run the app using the following command: ```bash python app.py ``` **Packaging and Distributing the App** Use a tool like PyInstaller to package the app for distribution. ```bash pyinstaller --onefile app.py ``` **Conclusion** In this article, we created a mobile photo editor application using Qt Quick and PySide6. We designed a simple UI using Qt Quick and wrote Python code to load, display, and apply a filter to the image. We also packaged the app for distribution using PyInstaller. **Leave a comment below if you have any questions or if you'd like to see any modifications to the code.**