Weird ComboBox behavior

Smatcher

Hello everyone,

I just stumbled on some weird behavior from the QML ComboBox. As soon as a ComboBox is located inside an asynchronous loaded component (It doesn't even have to be the Component top Item) the order of the ComboBox content is incorrect.
The style of the popup menu when opening the ComboBox also differs from a synchronously loaded ComboBox
The workaround I found is to to wrap the ComboBox inside a synchronous Loader.

Is this the intended behavior ?

Here is some sample code to illustrate this behavior

import QtQuick 2.4
import QtQuick.Controls 1.3
import QtQuick.Window 2.2
import QtQuick.Dialogs 1.2

Window {
    id: win
    title: qsTr("Hello World")
    width: 640
    height: 480
    visible: true

    property var model: ["item 1", "item 2", "item 3", "item 4", "item 5", "item 6", "item 7", "item 8"]

    Component {
        id: comboCompo
        Column {
            ComboBox {
                id: combo
                model: win.model
            }
        }
    }

    Component {
        id: wrappedCompo
        Loader {
            sourceComponent: comboCompo
            asynchronous: false
        }
    }

    Grid {
        columns: 3
        anchors.fill: parent
        GroupBox {
            // [1]
            title: "Synchronous"
            Loader {
                sourceComponent: comboCompo
                asynchronous: false
            }
        }

        GroupBox {
            // [2]
            title: "Asynchronous"
            Loader {
                sourceComponent: comboCompo
                asynchronous: true
            }
        }

        GroupBox {
            // [3]
            title: "Wrapped Asynchronous"
            Loader {
                sourceComponent: wrappedCompo
                asynchronous: true
            }
        }
    }
}

bnogal

i already reported this bug.

The problem is with the instantiator element.
When it runs async, it doesnt respect the order.
search for the bug and vote up...
by the moment, just dont use async, and care, because if a parent is loading a component async, and that component contains an instantiator (or a Combobox) your will get the same problem

Smatcher

Thank you for your reply.

I searched for the bug reports and only found reports about a crash when using Instantiator in an asynchronous Loader.
I will upvote your bug report if I can find it.

As for your suggestion to avoid async loader entirely it seems you are right. The workaround I talked about works in the simple example I gave but fails in more elaborate situations.

bnogal

https://bugreports.qt.io/browse/QTBUG-48053