ListView, PositionViewAtBeginning()

[JF002]

Hi!

I have a listview. When I click on an item, I clear the model and add new items in the model (from c++).
This works fine, and the listview is updated properly.

The only problem is that the position of the listview is not changed when the model is updated. For example, if I scroll down to the end of the list, click on the last item, then, the list would be updated with new items, but I would still see the last item.
I would like to set the position to the beginning of the list when an item is clicked, but I don't know how to do that...

I tried to call positionViewAtBeginning() and to set currentIndex to 0 with no luck. Any help?

Thanks!

[p3c0]

Hi,

As per the docs
bq. Note: methods should only be called after the Component has completed. To position the view at startup, this method should be called by Component.onCompleted, viz :
@
Component.onCompleted: positionViewAtBeginning()
@

So are you calling it in the above mentioned way ?

[JF002]

Yes, I tried to add this line, but it seems that Component.onCompleted is called only once, when the component is created at launch time.

But when I remove/add data from the model, the list is updated accordingly, but onComleted is not called.

So, how to change the position of the list after the component has been created?

[p3c0]

Hi,

Depending upon your use case i created a small code, it positions the item to the top after clearing the list.
May be this would be useful

@

import QtQuick 2.0

Rectangle {
width: 320; height: 240

ListModel {
    id: model
    ListElement {
        name: "PrePopulated"
        number: "32423434"
    }
    ListElement {
        name: "PrePopulated"
        number: "23423232"
    }
    ListElement {
        name: "PrePopulated"
        number: "23323234"
    }
}

Component {
    id: delegate
    Item {
        width: 320; height: 40
        Column {
            Text { text: '<b>Name:</b> ' + name }
            Text { text: '<b>Number:</b> ' + number }
        }

        MouseArea {
            anchors.fill: parent
            onClicked: {
                //If clicked on last item in list, clear the list and populate the new items
                if(index===view.count-1)
                {
                    console.log(index);
                    addItem();
                }
            }
        }
    }
}

ListView {
    id: view
    anchors.fill: parent
    model: model
    delegate: delegate
    highlight: Rectangle { color: "lightsteelblue"; radius: 5 }
    focus: true
}

//Click to add Items to listview
Text {
    id: add
    text: "Add Item"
    anchors.bottom: parent.bottom
    MouseArea {
        anchors.fill: parent
        onClicked: {
            model.append({name: "ButtonClick", number: Math.floor((Math.random()*10000)+1).toString()} );
            view.positionViewAtEnd();
        }
    }
}

function addItem()
{
    model.clear();
    for(var i=0; i<10; i++)
    {
        var data = {'name': "ItemClicked " + i.toString(), 'number': Math.floor((Math.random()*10000)+1).toString() };
        model.append(data);
        view.positionViewAtBeginning();
    }
}

}

@