PyQt5 series of tutorials (twenty-eight) mouse events

Software and hardware environment

Windows 10 64bit
Anaconda3 with python 3.8
PyQt5 5.15

Introduction

The mouse is an important means of interface interaction. In this article, we will take a look at several common mouse events in PyQt5 and their sample codes.

click event

The mouse click is actually the process of mouse press -> mouse release , and the corresponding mouse events are mousePressEvent and mouseReleaseEvent , so you only need to rewrite these two methods in the window. In addition, you can judge whether it is the left mouse button or the right mouse button by judging the button method of the event .

 def mousePressEvent(self, event): print('mousePressEvent') if event.button() == Qt.LeftButton: print('left') elif event.button() == Qt.RightButton: print('right') elif event.button() == Qt.MiddleButton: print('middle') def mouseReleaseEvent(self, event): print('mouseReleaseEvent')

If you want to get the coordinates of the mouse click position, you can get it through the related methods of event , see the following code snippet

 # 相对于窗口的位置x = event.x() y = event.y() # xy类型是QPoint，QPoint的x()和y()方法就是x和y的值xy = event.pos() print('x={}, y={}, xy={}, x={}, y={}'.format(x, y, xy, xy.x(), xy.y())) # 相对于屏幕的位置x_global = event.globalX() y_global = event.globalY() # xy_global类型是QPoint xy_global = event.globalPos() print('x_global={}, y_global={}, xy_global={}'.format(x_global, y_global, xy_global))

double click event

The double-click of the mouse is actually the process of double-click -> release of the mouse. The corresponding mouse events are mouseDoubleClickEvent and mouseReleaseEvent , so you only need to rewrite these two methods in the window.

 def mouseDoubleClickEvent(self, event): print('mouseDoubleClickEvent') def mouseReleaseEvent(self, event): print('mouseReleaseEvent')

mouse movement

Add mouse movement to the click event, mouse click -> hold down the mouse and move -> mouse release , the corresponding mouse events are mousePressEvent , mouseMoveEvent and mouseReleaseEvent , so you only need to override these three methods in the window. Can

 def mousePressEvent(self, event): print('mousePressEvent') def mouseMoveEvent(self, event): print('mouseMoveEvent') def mouseReleaseEvent(self, event): print('mouseReleaseEvent')

wheel event

Mouse wheel event needs to override wheelEvent

 def wheelEvent(self, event): print('wheelEvent')

Cursor in and out of window events

This cursor enters and exits the window, in fact, whether the focus is on the form, you need to override the methods enterEvent and leaveEvent

 def enterEvent(self, event): print('enterEvent') def leaveEvent(self, event): print('leaveEvent')

window close event

Here, the window closing event is also discussed in the mouse event. It is also a function that is often used in actual development. Here we need to rewrite the closeEvent method.

 def closeEvent(self, event): """重写closeEvent 方法，实现在窗口关闭时去执行一些功能""" reply = QMessageBox.question(self, '这是标题', "这是消息体", QMessageBox.Yes | QMessageBox.No, QMessageBox.No) if reply == QMessageBox.Yes: # 关闭窗口event.accept() else: # 取消event.ignore()

Source code download

https://github.com/xugaoxiang/learningPyQt5