Trying to recreate UI for flight time QGC

I have been trying to create a new UI in order to display the flight time in qgc software. I have designed the UI but I am not able to understand how I can fetch the Flight data and bind it to UI. I know about the factsystem and also there is a parameter named flightTime in vehicle.cc file but how I can use it ?

I want to bind the Flight time with the text variable in below code.

QGCLabel {
        anchors.horizontalCenter:  semicirc2.horizontalCenter
        anchors.top: semicirc2.top
        anchors.topMargin: 40
        width:                  parent.width
        horizontalAlignment:    Text.AlignHCenter
        wrapMode:               Text.WordWrap
        text:                   /*fact.shortDescription + (fact.units ? " (" + fact.units + ")" : "")*/ 'Qgc'
    }