Pyqt5 可拖動 QPushButton

Question

我有關於如何拖動和移動 QPushButton 的示例代碼。 該代碼的唯一問題是，當您拖動按鈕並釋放它時，按鈕狀態保持為選中狀態。

有人可以幫我更改代碼，以便在拖動按鈕並釋放按鈕后自動取消選中狀態。 所以，我不必點擊它來取消選中它。

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 ，這意味着您不會讓按鈕知道它實際上收到了鼠標釋放，從而使狀態保持為按下狀態。

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)

如果您將鼠標移動幾個像素（低於曼哈頓長度），您可以看到它的行為是正確的，因此您必須完全刪除該if塊，或者如果您想在返回之前調用self.setDown(False)避免發送clicked信號。