Control qml ListView from C++

sirnoname

Hi there,

I have two qml files from a designer (not me, I am not firm with qml). The loaded qml file is called main.qml the other mylistview.qml.

@import QtQuick 1.1

Item {
id: root
anchors.fill: parent

Item {
    id: mainViewArea
    anchors.fill: parent

    Background {
        id: background
    }

    ListView {
        id: listView@

As you can think, the main.cpp loads the main.qml which includes the mylistview.qml that finally shows a ListView vertical. No Problem here.
I use the following C++ code to load the QML. I cannot use QtQuick2 because no OpenGL on my embedded system:

@QDeclarativeView view;
view.setSource(QUrl::fromLocalFile(QCoreApplication::applicationDirPath() + QLatin1String("/main.qml")));@

I want to call the "incrementCurrentIndex" funktion of my listbox, but how?
Can I search subfunktions with this:

@// get root object
QObject *rootObject = dynamic_cast<QObject *>(view.rootObject());
//Invoke
QMetaObject::invokeMethod(
rootObject->findChild<QObject *>("listView"), // QML item
"incrementCurrentIndex" // name of the method to call
// without parameters??
);@

How do I call this in C++ after Invoke? Will the invoke find the mylistview.qml file? Do it find the increment function of a qml object?

leonardo.ramosantos

Hi,

First, to use findChild you need set your component's property "componentName" and use this name to find, like this:

QML File:
@ import QtQuick 1.1

Item {
    id: root
    anchors.fill: parent
 
    Item {
        id: mainViewArea
        anchors.fill: parent
 
        Background {
            id: background
        }
 
        ListView {
            objectName: "listView"
            id: listView

@

CPP file:
@ // get root object
QObject *rootObject = dynamic_cast<QObject *>(view.rootObject());
//Invoke
QObject *listViewObject = rootObject->findChild<QObject *>("listView");
@

Second, to call the function, if it needs parameter you need send it, because if you dont send it will raise a error telling no function was found. However, "incrementCurrentIndex" function doesn't need any parameter, so you don't need send parameters. Therefore you can call the way you were doing.

@QMetaObject::invokeMethod(
listViewObject, // QML item
"incrementCurrentIndex" // name of the method to call
);
@

Also you can set the currentIndex property like this:

@listViewObject.setProperty("currentIndex", 1);@

[]'s

sirnoname

Ahhh, object name was the missing part ;)
ID, model name etc. was tested, but object name is new to me.
Is it possible to search for ID instead of object name?

Connections are also possible, but I do not want to change the qml code so much.