Question

我正在尝试从QML调用Python方法并使用返回值。

QML从Python方法接收undefined。

当传回Python时，它只是一个空字符串。

import sys
from PyQt5.QtCore import QObject, pyqtSlot
from PyQt5.QtWidgets import QApplication
from PyQt5.QtQml import QQmlApplicationEngine


class InPython(QObject):
    @pyqtSlot(str, )
    def login(self, Login):
        print(Login)
        return "a"


if __name__ == "__main__":
    app = QApplication(sys.argv)
    engine = QQmlApplicationEngine()
    context = engine.rootContext()
    context.setContextProperty("main", engine)
    engine.load('Main.qml')
    win = engine.rootObjects()[0]

    inPython = InPython()
    context.setContextProperty("loginManger", inPython)

    win.show()
    sys.exit(app.exec_())

Main.qml

import QtQuick 2.3
import QtQuick.Controls 1.2
import QtQuick.Layouts 1.0

ApplicationWindow {
    width: 800;
    height: 600;

    ColumnLayout {
        anchors.horizontalCenter: parent.horizontalCenter
        anchors.verticalCenter: parent.verticalCenter
        anchors.margins: 3
        spacing: 3
        Column {
            spacing: 20
            anchors.horizontalCenter: parent.horizontalCenter

            TextField {
                id: login
                objectName: "login"
                placeholderText: qsTr("Login")
                focus: true
                Layout.fillWidth: true
                onAccepted: {
                    btnSubmit.clicked()
                }
            }

            Button {
                id: btnSubmit
                objectName: "btnSubmit"
                text: qsTr("Login")
                Layout.fillWidth: true
                onClicked: {
                    var a = loginManger.login(login.text);
                    console.log(a);
                    loginManger.login(a); // Python recieves ''
                    if (a === "a"){
                        login.text = "SUCCESS"
                    }
                }
            }
        }
    }
}

Answer 1

您还需要告诉您从方法中返回的内容（请注意pyqtslot装饰器中的class InPython(QObject): @pyqtSlot(str, result=str) # also works: @pyqtSlot(QVariant, result=QVariant) def login(self, Login): print(Login) return "a"：

result

result - 结果的类型，可以是Python类型的对象，也可以是指定C ++类型的字符串。这可能只作为关键字给出参数。

（以及[{"id":0,"name":"Biatrix"},{"id":1,"name":"Bill"},{"id":2,"name":"O-ren"}]参数）

从Python方法获取QML中的返回值

1 个答案: