I have a pyqtgraph.ViewBox widget with an image in it. The mouse is enabled, so I can select a rectangle on the image and it will be zoomed. But there is an unwanted feature, the zooming occurs on the mouse wheel scrolling aswell.
How can I disable the mouse wheel only, and leave the rest as is?
from PyQt5.QtWidgets import QApplication, QMainWindow
import pyqtgraph as pg
import cv2
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
pg.setConfigOption('imageAxisOrder', 'row-major')
pg.setConfigOption('leftButtonPan', False) # if False, then dragging the left mouse button draws a rectangle
self.grid = pg.GraphicsLayoutWidget()
self.top_left = self.grid.addViewBox(row=1, col=1)
image = cv2.imread('/path/to/your/image.jpg', cv2.IMREAD_UNCHANGED)
self.image_item = pg.ImageItem()
self.image_item.setImage(image)
self.top_left.addItem(self.image_item)
self.setCentralWidget(self.grid)
def main():
app = QApplication([])
window = MainWindow()
window.show()
app.exec_()
if __name__ == '__main__':
main()
You can install an event filter on the ViewBox and catch the mouse wheel event, in this case QEvent.GraphicsSceneWheel.
from PyQt5.QtWidgets import QApplication, QMainWindow
from PyQt5.QtCore import QEvent
import pyqtgraph as pg
import cv2
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
pg.setConfigOption('imageAxisOrder', 'row-major')
pg.setConfigOption('leftButtonPan', False) # if False, then dragging the left mouse button draws a rectangle
self.grid = pg.GraphicsLayoutWidget()
self.top_left = self.grid.addViewBox(row=1, col=1)
self.top_left.installEventFilter(self)
image = cv2.imread('/path/to/your/image.jpg', cv2.IMREAD_UNCHANGED)
self.image_item = pg.ImageItem()
self.image_item.setImage(image)
self.top_left.addItem(self.image_item)
self.setCentralWidget(self.grid)
def eventFilter(self, watched, event):
if event.type() == QEvent.GraphicsSceneWheel:
return True
return super().eventFilter(watched, event)