[Interest] ListView not start at index 0 when is Horizontal

[Federico Buti]

Hi Gianluca,
it's hard to say if it is a bug or not. The problem is anyway related to
the sizing of the list, i.e. if you set listHistory.width to

width: parent.width

the problem disappears. If you set a similar constraint for the height and
set the ListView to the vertical layout the same, odd, behaviour occurs.

Instead of using such constraints, what about using a layout to size your
three elements? Something involving a RowLayout, for instance, works
perfectly. See the modified code below:

import QtQuick 2.4

import QtQuick.Window 2.2

import QtQuick.Layouts 1.1


Window {

    visible: true

    width: 400

    height: 400

        RowLayout {

        anchors.fill: parent

                Item {

            id: previous

            Layout.preferredWidth: parent.width / 3

            Layout.fillHeight: true

        }

                ListView {

            id: listHistory

            Layout.preferredWidth: parent.width / 3

            Layout.fillHeight: true

            clip: true

            orientation: ListView.Horizontal

            snapMode: ListView.SnapToItem

            highlightRangeMode: ListView.StrictlyEnforceRange

            onCurrentIndexChanged: console.log( "Current Index: "+currentIndex )

            model: modelHistory

            delegate: Item {

                width: listHistory.width

                height: listHistory.height

                Text {

                    width: parent.width

                    anchors.bottom: parent.verticalCenter

                                        font.pixelSize: 20 //* mm

                    minimumPixelSize: 10 //* mm

                    fontSizeMode: Text.Fit

                    horizontalAlignment: Text.AlignHCenter

                    text: year

                }

                Text {

                                        width: parent.width

                    height: parent.height/2-1.5 //* mm

                    anchors.bottom: parent.bottom

                    font.pixelSize: 20 //* mm

                    minimumPixelSize: 10 //* mm

                    fontSizeMode: Text.Fit

                    horizontalAlignment: Text.AlignHCenter

                    wrapMode: Text.Wrap

                    text: what

                }

            }

        }

                Item {

            id: next

            Layout.preferredWidth: parent.width / 3

            Layout.fillHeight: true

        }

    }

}


Cheers,

F.


---
Federico Buti

On 6 April 2015 at 11:15, Gianluca <gmaxera at gmail.com> wrote:

> Dear all,
> I’m experiencing a unexpected behavior:
> I have a ListView in QML that display data from a ListModel.
> The dimension of ListView is set in such a way that only one element
> delegate is display at time.
> When I configure the ListView to be Vertical, then the first item
> displayed is the first item on the ListModel.
> But when I configure the ListView to be Horizontal, then the first item
> displayed is not the first item on the ListModel … but one in the middle.
> Why ??
> Forcing the property currentIndex to 0 do not solve the problem.
> Calling positionViewAtBeginning do not solve the problem :-(
>
> What else I can do ?
>
> // Code of ListView:
>                 ListView {
>                         id: listHistory
>                         anchors.centerIn: parent
>                         height: parent.height
>                         width: parent.width-previous.width-next.width
>                         clip: true
>                         orientation: ListView.Horizontal
>                         snapMode: ListView.SnapToItem
>                         highlightRangeMode: ListView.StrictlyEnforceRange
>                         onCurrentIndexChanged: console.log( "Current
> Index: "+currentIndex )
>                         model: modelHistory
>                         delegate: Item {
>                                 width: listHistory.width
>                                 height: listHistory.height
>                                 Text {
>                                         width: parent.width
>                                         anchors.bottom:
> parent.verticalCenter
>                                         color: "white"
>                                         font.pixelSize: 8.5*mm
>                                         minimumPixelSize: 4*mm
>                                         fontSizeMode: Text.Fit
>                                         horizontalAlignment:
> Text.AlignHCenter
>                                         text: year
>                                 }
>                                 Text {
>                                         color: "white"
>                                         width: parent.width
>                                         height: parent.height/2-1.5*mm
>                                         anchors.bottom: parent.bottom
>                                         font.pixelSize: 2.4*mm
>                                         minimumPixelSize: 1*mm
>                                         fontSizeMode: Text.Fit
>                                         horizontalAlignment:
> Text.AlignHCenter
>                                         wrapMode: Text.Wrap
>                                         text: what
>                                 }
>                         }
>                 }
>
> // On the console I get the following message:
> qml: Current Index: 0
> qml: Current Index: 19
>
> But Who change the current index to 19 ??
>
> Thanks,
> Gianluca.
>
>
> _______________________________________________
> Interest mailing list
> Interest at qt-project.org
> http://lists.qt-project.org/mailman/listinfo/interest
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.qt-project.org/pipermail/interest/attachments/20150406/6ab69902/attachment.html>