我正在尝试捕获key_tab事件,但是没有运气.我意识到只有在没有其他小部件的情况下它才起作用,因此光标没有去处,然后我才能使事件返回.这是一个简化的代码示例.

class MyCombo(QComboBox):

    def __init__(self, parent=None):
        super(MyCombo, self).__init__(parent)
        self.setEditable(True)

    def keyPressEvent(self, event):
        if (event.type() == QEvent.KeyPress) and (event.key() == Qt.Key_Tab):
            print "tab pressed"
        elif event.key() == Qt.Key_Return:
            print "return pressed"
        else:
            QComboBox.keyPressEvent(self, event)

class Form_1(QDialog):

    def __init__(self, parent=None):
        super(Form_1, self).__init__(parent)
        self.combo = MyCombo()
        self.line = QLineEdit()
        layout = QVBoxLayout()
        layout.addWidget(self.combo)
        layout.addWidget(self.line)
        self.setLayout(layout)

app = QApplication(sys.argv)
form = Form_1()
form.show()
app.exec_()

如果我注释掉以下两行

self.line = QLineEdit()
layout.addWidget(self.line)

那么就可以了,因为表单上只剩下一个小部件.

我要去哪里错了？

干杯,乔

解决方法:

显然,Key_Tab新闻事件从未传递给任何处理程序,而是传递给setFocus(),因此,为了拦截Key_Tab事件,我们需要自己实现event()方法.
所以这是新代码：

class MyCombo(QComboBox):

    def __init__(self, parent=None):
        super(MyCombo, self).__init__(parent)
        self.setEditable(True)

    def keyPressEvent(self, event):
        if event.key() == Qt.Key_Return:
            print "return pressed"
        else:
            QComboBox.keyPressEvent(self, event)

    def event(self, event):
        if event.type() == QEvent.KeyPress and event.key() == Qt.Key_Tab:
            print "tab pressed"
            return False
        return QWidget.event(self, event)

class Form_1(QDialog):

    def __init__(self, parent=None):
        super(Form_1, self).__init__(parent)
        self.combo = MyCombo()
        self.line = QLineEdit()
        layout = QVBoxLayout()
        layout.addWidget(self.combo)
        layout.addWidget(self.line)
        self.setLayout(layout)