Signals between pages - qt

Question

I am trying to communicate between 2 QML pages.
In my page Main.qml I receive a signal from my C++ code. On receiving this signal I want text on InputPage.qml to change. This page is shown within Main.qml using a Loader. The only way I could find so far is to set up another signal between the 2 pages. However, I think there is a much easier way to do this. I already tried this way but I could not get it to work. So before I proceed I would like to know if this is the right method or not.
Any ideas on how to do this, and if the method described above is the correct one?
My code:
Main.qml
Item {
id: screen_InputPage
width: 1920
height: 930
anchors.left: parent.left
anchors.leftMargin: 0
anchors.top: parent.top
anchors.topMargin: 100
visible: false
opacity: 1
Loader {//Loads the pages
id: pageLoader_ID2
source: "inputPage.qml"
}
}
And i would like to access the text(and maybe functions) placed on inputPage.qml
Text {
id: text_volume_perc_ID1
height: 48
text: qsTr("50")
anchors.right: parent.right
anchors.rightMargin: 0
verticalAlignment: Text.AlignVCenter
horizontalAlignment: Text.AlignHCenter
anchors.top: parent.top
anchors.topMargin: 126
anchors.left: parent.left
anchors.leftMargin: 0
font.pixelSize: 42
}

Answer 1

To access the created object, you can use
idLoader.item.idInputpage.idText.text
I propose that you load objects dynamically to improve performance. To do so you can create your own CustomLoader.qml:
CustomLoader.qml
import QtQuick 2.0
Item {
id: idRoot
width: childrenRect.width
height: childrenRect.height
property Item createdObject
property string source
function fnSourceChange() {
if (""!== source){
var component
// create component
component = Qt.createComponent(source)
if (Component.Ready === component.status) {
createdObject= component.createObject(idRoot)
if(!createdObject)
console.log("Loader::Could not create the object ")
}
else {
console.log("Loader::Could not create panel", component.errorString(), "component has errors")
}
}
else {
createdObject.destroy();
createdObject = null
// unComment this line if you want to force the garbage collector
//gc()
}
}
onSourceChanged: {
fnSourceChange()
}
// even without that it should detect the source change and create it
// you can unComment this line if you want, but like that it will parse the function
// two times one on the sourceChanged signal and on on in this handler
// print the source or somthing in the function and you'll see
// Component.onCompleted: fnSourceChange()
}
main.qml
import QtQuick 2.0
Item {
id: screen_InputPage
width: 1920
height: 930
anchors.left: parent.left
anchors.leftMargin: 0
anchors.top: parent.top
anchors.topMargin: 100
visible: false
opacity: 1
CustomLoader{
id: pageLoader_ID2
source: "inputPage.qml"
}
}
InputPage.qml
import QtQuick 2.0
Item {
width: 800
height: 480
property alias text: idText.text
property alias label: idText
property alias rect: idRect
Text{
id: idText
}
Rectangle{
id: idRect
width: 100
height: 200
}
}
In your main add :
//or another scope like click button
Component.onCompleted: {
pageLoader_ID2.createdObject.text = "hello"
pageLoader_ID2.createdObject.rect.color = "red"
}