How to calculate line while wrapping text in QLIstview

prankur.sarbhai

Hi,

I am working on messaging application. I have a delegate which arrange text in different rect to draw text. I have to show - Name, date and time, Subject, Message , message status Icon. It doesnt work well (ie it create extra lines) in case if word is long . There is some problem in calculating in sizeHint but i tried different scenarios and couldnt make it working . for long text there are always extra lines coming in QLIstView .
Please check the link below :
!http://tinypic.com/r/34dt1de/5(Message shown in QListView)!

Here's the code for this:
@
QSize ConversationViewItemDelegate::sizeHint(const QStyleOptionViewItem& , const QModelIndex& index) const
{
QString str = index.data().toString();

QListView *view = (QListView*)parent();
QFontMetrics fontMetrics(view->font());

QStringList words = str.split(QChar(' '));
words.removeAll("\n");
QStringList lines = str.split(QChar('\n'));
int noOfLines = lines.size();

QRectF boundingRect = fontMetrics.boundingRect(str);
int width = view->viewport()->width() -35;
int height = boundingRect.height();
int times = 0;
while (words.size() > 0)
{
    times++;
    qreal lineWidth = 0;
    bool enoughSpace = true;
    do
    {
        QString word = words.first();
        qreal wordWidth = fontMetrics.width(word);
        wordWidth = wordWidth + lineWidth;
        lineWidth = 0;
        if(wordWidth > width)
        {
            times++;
            while(wordWidth > width )
            {
                times++;
                wordWidth -= width;
            }
            lineWidth += wordWidth;
            lineWidth += fontMetrics.width(QChar(' '));
            words.removeFirst();
        }
        else if (wordWidth < width)
        {
            lineWidth += wordWidth;
            lineWidth += fontMetrics.width(QChar(' '));
            words.removeFirst();
        }
        else
            enoughSpace = false;
    }
    while (enoughSpace && words.size() > 0);
}

height = height * times  + (noOfLines + 3)* boundingRect.height() - times;
QSize sizeOfSubjectField = QSize();
if (!index.model()->data(index, ConversationViewMsgSubjectRole).toString().isEmpty())
{
 QString subject = "Subject: " +  index.model()->data(index, ConversationViewMsgSubjectRole).toString();
 sizeHintforSubject(subject);
}
else
{
    height = height - boundingRect.height();
}

height += sizeOfSubjectField.height();
return QSize(width,  height);

}

QSize ConversationViewItemDelegate::sizeHintforSubject(QString str) const
{
QListView p = (QListView)parent();
QString text = str;
QFontMetrics fm(p->font());

float rw = float(p->viewport()->size().width());
float tw = fm.width(text);
float ratio = tw/rw;
int lines = int(ratio) + 1;
return QSize(rw,lines*fm.height());

}

@

prankur.sarbhai

the paint function code is as follows:
@void ConversationViewItemDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex & index) const
{

QString displayName = index.model()->data(index, ConversationViewDisplayNameRole).toString();
QString dateTime = index.model()->data(index, ConversationViewDateTimeRole).toString();
bool messageStatus = index.model()->data(index, ConversationViewMsgReadRole).toBool();
QString textMessage = index.model()->data(index, ConversationViewMessageRole).toString();

QString subject = QString();

if (!index.model()->data(index, ConversationViewMsgSubjectRole).toString().isEmpty())
{
 subject = "Subject: " +  index.model()->data(index, ConversationViewMsgSubjectRole).toString();
}

QIcon messageStatusIcon =  index.model()->data(index, ConversationViewMsgStatusIcon).value<QIcon>();
QPixmap pMessageStatusPixmap = messageStatusIcon.pixmap(option.decorationSize);

QRect messageRect = option.rect;
QRect dateTimeRect = option.rect;
QRect boundaryRect = option.rect;
QRect displayNameRect = option.rect;
QRect sendMessageIconRect = option.rect;
QRect subjectRect = option.rect;

dateTimeRect.setTop(dateTimeRect.top()+5);
dateTimeRect.setBottom(dateTimeRect.top()+15);
dateTimeRect.setLeft(dateTimeRect.right()- 110);
dateTimeRect.setRight(dateTimeRect.right()-5);

displayNameRect.setTop(displayNameRect.top()+5);
displayNameRect.setBottom(displayNameRect.top()+15);
displayNameRect.setLeft(displayNameRect.left()+5);
displayNameRect.setRight(displayNameRect.right()-120);

boundaryRect.setRight(boundaryRect.right() - 2);
boundaryRect.setLeft(boundaryRect.left() + 2);

if(!index.model()->data(index, ConversationViewMsgSubjectRole).toString().isEmpty())
{
    QSize a  = sizeHintforSubject(subject);
    subjectRect.setTop(dateTimeRect.bottom() + 2);
    subjectRect.setLeft(subjectRect.left() + 10);
    subjectRect.setRight(subjectRect.right() - 35);
    subjectRect.setBottom(subjectRect.top() + a.height());

    messageRect.setTop(subjectRect.bottom()+ 5);
    messageRect.setRight(messageRect.right() - 5);
}
else
{
    messageRect.setTop(dateTimeRect.bottom()+10);
    messageRect.setRight(messageRect.right() - 25);
}
messageRect.setLeft(messageRect.left() + 10);
messageRect.setBottom(messageRect.bottom() - 5);

sendMessageIconRect.setTop(dateTimeRect.bottom()+2 );
sendMessageIconRect.setRight(sendMessageIconRect.right()-5);
sendMessageIconRect.setLeft(sendMessageIconRect.right()- 20);
sendMessageIconRect.setBottom(dateTimeRect.bottom()+20);

QFont boldFont = QApplication::font();
boldFont.setBold(true);
QFont normalFont = QApplication::font();
QFont italicFont = QApplication::font();
italicFont.setItalic(true);

//Change color in message is UNREAD
if(!messageStatus)
{
   painter->fillRect(boundaryRect, "#C0C0C0");
}
//Set selected Message item color
if (option.state & QStyle::State_Selected)
     painter->fillRect(boundaryRect, "#C8E0FD");

painter->save();
painter->drawRoundedRect(boundaryRect, 3, 3);
painter->drawText(dateTimeRect, Qt::AlignLeft  , dateTime);
painter->drawPixmap(sendMessageIconRect, pMessageStatusPixmap);

QTextOption opt ;
opt.setWrapMode(QTextOption::WrapAtWordBoundaryOrAnywhere);
painter->drawText(messageRect,textMessage, opt );

painter->setFont(italicFont);
painter->drawText(subjectRect,subject, opt );
painter->setFont(boldFont);
painter->drawText(displayNameRect, Qt::AlignLeft  , displayName);


painter->restore();

}@

some how the pic didnt come . the link for it is http://tinypic.com/r/34dt1de/5

prankur.sarbhai

Any suggestions ????

raven-worx

what is exactly the problem?!
the image you've posted seems ok?

prankur.sarbhai

Hi Raven,

Thanks for the reply. Actually I am trying to make a chat view using QLIstview to show previous msges. The problem which i am facing is that where the text is very long there are extra space (extra number of lines from size hint) in list view item. i checked the previous post and wrote the size hint , it works only for small texts. If i show long text having long words then extra spaces comes in list view item. I am using WrapAtWordBoundaryOrAnywhere .

Regards,
Prankur

raven-worx

maybe your text contains "\n" which cause the extra line breaks?