Error when opens FileDialog

[summerfang]

I have a very simple example code,and when I clicked the button to open the filedialog, the dialog pops but the following errors appear and the program crashes. It's Qt 5.7 under Debian.

Error:

(NewOptisort:2246): GLib-GObject-WARNING **: cannot register existing type 'GdkWindow'
(NewOptisort:2246): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed
(NewOptisort:2246): GLib-GObject-CRITICAL **: g_type_register_static: assertion 'parent_type > 0' failed
(NewOptisort:2246): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

code:

import QtQuick 2.7
import QtQuick.Controls 2.0
import QtQuick.Layouts 1.0
import QtQuick.Dialogs 1.2


ApplicationWindow {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")

    FileDialog
    {
        id:file
    }


    Button {
        id: button
        x: 93
        y: 86
        text: qsTr("Button")
        onClicked: {file.open()}
    }

}

I found the reason may have something to do with openCV. In my .pro, I have LIBS += pkg-config opencv --libs ,
if I comment this line and rebuild the project, the error disappear. But the popped dialog has another layout, different from the look from the test with openCV. I don't know why this happens and I must use openCV and FileDialog together.

I spent already one day to delete the fragment installation packages I don't need in my system, doesn't help.
Thanks in advance for answering.

[Eddy]

@summerfang

I know you are using Qt5.7
But in the docs of Qt5.9 about FileDialog you can read :

Availability
A native platform file dialog is currently available on the following platforms:

• iOS
• Linux (when running with the GTK+ platform theme)
• macOS
• Windows
• Win RT
  So I think you will have to take another approach if the newer Qt version says it only supports GTK+.

Also you could ask on the mailing lists if there is a workaround. Qt developers are more likely to hang out there. This is more a user oriented forum.

hope it helps.

Eddy

[summerfang]

@Eddy Thanks a lot but I do have GTK+ and if I don't link to opencv the code works perfectly. I am kind of new and I don't know about the mailing list, I'll check it, thanks!