QScrollArea wrong behavior on the Symbian platform

[sq_vasya]

Hello all.

I have an issue with scrolling.

This code works fine on the windows platform but it does not scroll on the Symbian one.

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    {
    QScrollArea* scrollArea = new QScrollArea( this );
    scrollArea->setHorizontalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
    scrollArea->setFrameStyle( QFrame::NoFrame );
 
    QWidget* scrollWidget = new QWidget(scrollArea);
    QVBoxLayout* verticalLayout = new QVBoxLayout(scrollWidget);
    scrollWidget->setLayout(verticalLayout);
 
    QLabel* label = new QLabel( "After university in 1977, she joined the Radio Times as a sub-editor before moving in 1978 to the Times Higher Education Supplement as the deputy literary editor. She began freelance writing at the same time. Truss was Literary Editor of The Listener (1986–90) and was an arts and books reviewer for The Independent on Sunday before joining The Times in 1991, where first she spent six years writing television criticism, illustrated by John Minnion, followed by four years as a sports columnist. She won Columnist of the Year for her work for Woman's Journal. She now reviews books for The Sunday Times. Her book Eats, Shoots & Leaves (November 2003), about the misuse of punctuation, became a bestseller in both Britain and the United States. The book's declaration for a Zero Tolerance Approach to Punctuation is considered a rallying call for punctuation sticklers of the world. In 2005 she released a book on rudeness titled Talk to the Hand: the utter bloody rudeness of the world today (or six good reasons to stay home and bolt the door)." );
    label->setWordWrap( true );
    verticalLayout->addWidget(label);
 
    scrollArea->setWidget(scrollWidget);
    QHBoxLayout* horizontalLayout = new QHBoxLayout();
    horizontalLayout->addWidget( scrollArea );
    setLayout( horizontalLayout );
    }

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    {
    QScrollArea* scrollArea = new QScrollArea( this );
    scrollArea->setHorizontalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
    scrollArea->setFrameStyle( QFrame::NoFrame );

    QWidget* scrollWidget = new QWidget(scrollArea);
    QVBoxLayout* verticalLayout = new QVBoxLayout(scrollWidget);
    scrollWidget->setLayout(verticalLayout);

    QLabel* label = new QLabel( "After university in 1977, she joined the Radio Times as a sub-editor before moving in 1978 to the Times Higher Education Supplement as the deputy literary editor. She began freelance writing at the same time. Truss was Literary Editor of The Listener (1986–90) and was an arts and books reviewer for The Independent on Sunday before joining The Times in 1991, where first she spent six years writing television criticism, illustrated by John Minnion, followed by four years as a sports columnist. She won Columnist of the Year for her work for Woman's Journal. She now reviews books for The Sunday Times. Her book Eats, Shoots & Leaves (November 2003), about the misuse of punctuation, became a bestseller in both Britain and the United States. The book's declaration for a Zero Tolerance Approach to Punctuation is considered a rallying call for punctuation sticklers of the world. In 2005 she released a book on rudeness titled Talk to the Hand: the utter bloody rudeness of the world today (or six good reasons to stay home and bolt the door)." );
    label->setWordWrap( true );
    verticalLayout->addWidget(label);

    scrollArea->setWidget(scrollWidget);
    QHBoxLayout* horizontalLayout = new QHBoxLayout();
    horizontalLayout->addWidget( scrollArea );
    setLayout( horizontalLayout );
    }

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Seems like wrong widget has focus.

Does anybody know how to fix it. I've tried a lot of variants how to do it, google a lot but without any success.
Could you help me please?

[wysota]

Do you have the scroll bar visible?

[sq_vasya]

Do you have the scroll bar visible?

Yes, I have. And it works on touch devices correctly. On the non-touch devices it does not work.

[wysota]

How are you trying to scroll the area then?

[sq_vasya]

How are you trying to scroll the area then?

Just with cursor.

[wysota]

Does it work on Windows if you try to scroll using the cursor keys without first making the scroll area have focus? I doubt that. If you want to send key events to some widget, this widget needs to have focus. If you want to avoid that, install an event filter on your other widgets and forward cursor key events to the scroll area. You can install an event filter on the application object to intercept all events in your application. Just prevent falling into an infinite loop when forwarding the events to the scroll area - your filter will catch those as well. Note that you shouldn't need to do that if you don't have any widgets accepting focus outside or inside the scroll area.

[sq_vasya]

Does it work on Windows if you try to scroll using the cursor keys without first making the scroll area have focus? I doubt that. If you want to send key events to some widget, this widget needs to have focus. If you want to avoid that, install an event filter on your other widgets and forward cursor key events to the scroll area. You can install an event filter on the application object to intercept all events in your application. Just prevent falling into an infinite loop when forwarding the events to the scroll area - your filter will catch those as well. Note that you shouldn't need to do that if you don't have any widgets accepting focus outside or inside the scroll area.

- Yes it work on Windows if I try to scroll using the cursor keys without first making the scroll area have focus.
- I try to set focus on the scroll area

void Widget::keyPressEvent(QKeyEvent* aEvent)
    {
    iScrollArea->setFocus();
    qDebug( "Widget::keyPressEvent." );
    }

void Widget::keyPressEvent(QKeyEvent* aEvent)
    {
    iScrollArea->setFocus();
    qDebug( "Widget::keyPressEvent." );
    }

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but it does not work.
- how to forward events to specified widget?

[wysota]

- Yes it work on Windows if I try to scroll using the cursor keys without first making the scroll area have focus.

Hail Bill Gates then! It doesn't work on Linux.

- I try to set focus on the scroll area

If you execute some code in a method that never gets called then it will never execute. Key events are delivered to widgets that have focus. So if your "Widget" instance doesn't have focus, it won't receive the key press event.

- how to forward events to specified widget?

Send/post the widget an event you wish it to receive.

[sq_vasya]

Hail Bill Gates then! It doesn't work on Linux.

If you execute some code in a method that never gets called then it will never execute. Key events are delivered to widgets that have focus. So if your "Widget" instance doesn't have focus, it won't receive the key press event.

It calls. I have logged.