Hi again. I found way to cause crash if I use Qt.createComponent + createObject + FileDialog +Controls2.StackView. Here is my code:
Main.qml (for this example I just create qml app from QtCreator template and rewrite main.qml)
import QtQuick 2.7
import QtQuick.Layouts 1.1
import QtQuick.Controls 2.0
ApplicationWindow {
id: window
visible: true
height: 300
ColumnLayout{
Button {
text: "Push"
onClicked: {
var component = Qt.createComponent("file:///D:/aknew-Data/Sandbox/build-test-Desktop_Qt_5_7_0_MinGW_32bit-Debug/debug/TestQML.qml")
switch (component.status) {
case Component.Ready:
var form = component.createObject()
stackView.push(form)
break
case Component.Error:
console.log(component.errorString())
break
}
}
}
Button {
text: "Pop"
onClicked: stackView.pop()
}
StackView {
id: stackView
height: 100
width: 100
initialItem: Rectangle {
Component.onDestruction: console.log(
"Cyan Destruction Beginning!")
color: "cyan"
}
}
}
}
TestQml which I loadfrom file:
import QtQuick 2.5
import QtQuick.Controls 2.0
import QtQuick.Dialogs 1.2
Rectangle {
Component.onDestruction: console.log("Green Destruction Beginning!")
color: "Green"
FileDialog {}
}
If I push-pop TestQml few times, I got QCoreApplication::postEvent: Unexpected null receiver during push (really during component.createObject() ) and app crashes. It seems that reason is that js garbage collector destroy previous instances of component , but something in C++ still have pointer to it (I suppose so because I have seen some methods with name like QV4::MemoryManager::runGC in call stack when I tried to debug this crash, but it happens rarely with active debugger and doesn't happen if I make push-pop sequence from code). I figure out that if I remove FileDialog, the app does not crash.
I understand that my code can be incorrect for Controls 2, but I haven't had any system notification about it, this code is result of migration from Controls 1 and it is work in general (when I don't use FileDialog), so I think this situation is should be at least described because figure out what causes this crash was not easy
My environment is Qt Creator 4.0.2, Qt 5.7.0, MinGW 32 bit, OS Win 8.1 64 bit, if you need some other information, please, I ready to answer, but maybe not very fast - I use qt only in my pet project now.
