Pyqt5 可拖动 QPushButton

Question

我有关于如何拖动和移动 QPushButton 的示例代码。 该代码的唯一问题是，当您拖动按钮并释放它时，按钮状态保持为选中状态。

有人可以帮我更改代码，以便在拖动按钮并释放按钮后自动取消选中状态。 所以，我不必点击它来取消选中它。

from PyQt5.QtWidgets import QApplication, QWidget, QPushButton
from PyQt5.QtCore import Qt

class DragButton(QPushButton):

    def mousePressEvent(self, event):
        self.__mousePressPos = None
        self.__mouseMovePos = None
        if event.button() == Qt.LeftButton:
            self.__mousePressPos = event.globalPos()
            self.__mouseMovePos = event.globalPos()

        super(DragButton, self).mousePressEvent(event)

    def mouseMoveEvent(self, event):
        if event.buttons() == Qt.LeftButton:
            # adjust offset from clicked point to origin of widget
            currPos = self.mapToGlobal(self.pos())
            globalPos = event.globalPos()
            diff = globalPos - self.__mouseMovePos
            newPos = self.mapFromGlobal(currPos + diff)
            self.move(newPos)

            self.__mouseMovePos = globalPos

        super(DragButton, self).mouseMoveEvent(event)

    def mouseReleaseEvent(self, event):
        if self.__mousePressPos is not None:
            moved = event.globalPos() - self.__mousePressPos 
            if moved.manhattanLength() > 3:
                event.ignore()
                return

        super(DragButton, self).mouseReleaseEvent(event)

def clicked():
    print ("click as normal!")

if __name__ == "__main__":
    app = QApplication([])
    w   = QWidget()
    w.resize(800,600)

    button = DragButton("Drag", w)
    button.clicked.connect(clicked)

    w.show()
    app.exec_() 

Answer 1

您在 mouseReleaseEvent 中return ，这意味着您不会让按钮知道它实际上收到了鼠标释放，从而使状态保持为按下状态。

def mouseReleaseEvent(self, event):
    if self.__mousePressPos is not None:
        moved = event.globalPos() - self.__mousePressPos 
        if moved.manhattanLength() > 3:
            event.ignore()
            return # <-- the problem is here!

    super(DragButton, self).mouseReleaseEvent(event)

如果您将鼠标移动几个像素（低于曼哈顿长度），您可以看到它的行为是正确的，因此您必须完全删除该if块，或者如果您想在返回之前调用self.setDown(False)避免发送clicked信号。