How to get the className of activeFocusControl in QML ApplicationWindow - qt

Question

I try
ApplicationWindow {
onActiveFocusControlChanged: {
console.log(activeFocusControl)
console.log(activeFocusControl.objectName)
}
}
ouput:
qml: QQuickTextField(0xa6ec00) //the 'activeFocusControl'
qml: //the 'activeFocusControl.objectName'
qml: QQuickButton(0xd7ccb0)
qml:
I want to
onActiveFocusControlChanged: {
if (activeFocusControl.className == "QQuickTextField") {
//do something
}
else if (activeFocusControl.className == "QQuickButton") {
//do something
}
but the "className" method does not exist
so how i can do it?
sorry, my english is pool, and thank you

Answer 1

There is no method to access the className from qml, so a possible solution is to create a helper from c ++ as shown below:
#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQmlContext>
#include <QObject>
class Helper : public QObject
{
Q_OBJECT
public:
Q_INVOKABLE QString getClassName(QObject *obj) const{
return obj? obj->metaObject()->className(): "";
}
};
#include "main.moc"
int main(int argc, char *argv[])
{
#if defined(Q_OS_WIN)
QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
#endif
QGuiApplication app(argc, argv);
Helper helper;
QQmlApplicationEngine engine;
engine.rootContext()->setContextProperty("helper", &helper);
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
if (engine.rootObjects().isEmpty())
return -1;
return app.exec();
}
then it is used on the QML side:
import QtQuick 2.9
import QtQuick.Window 2.2
import QtQuick.Controls 2.3
ApplicationWindow {
visible: true
width: 640
height: 480
title: qsTr("Hello World")
Button {
id: button
x: 270
y: 47
text: qsTr("Button")
}
TextField {
id: textField
x: 220
y: 169
text: qsTr("Text Field")
}
onActiveFocusControlChanged: {
var className = helper.getClassName(activeFocusControl)
switch(className){
case "QQuickTextField":
console.log("I am QQuickTextField")
break
case "QQuickButton":
console.log("I am QQuickButton")
break
default:
console.log("empty")
}
}
}
The complete example can be found at the following link.