QTreeWidget: change font size

[sitesv]

Hello!
Is it possible to change the font size while using QStyledItemDelegate?
In 'paint" section trying to do next:

QStyleOptionViewItemV4 viewOption = option;
initStyleOption(&viewOption, index);
viewOption.font.setPixelSize(8);

But it is still not working...

[SGaist]

Hi,

Please show the complete code of your custom item delegated.

Note that if it's just a question of font, you can set the Qt::FontRole of you model items.

[sitesv]

@SGaist

void TfDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    QStyleOptionViewItemV4 viewOption = option;
    initStyleOption(&viewOption, index);
    viewOption.font.setPixelSize(8);

    painter->save();

    QBrush brush = QBrush(Qt::red);
    QRect rect = viewOption.rect;

    //make some drawing
    painter->fillRect(rect, brush);

    //draw text and frame
    QPen pen;
    pen.setColor(Qt::black);
    pen.setWidth(2);
    painter->setPen(pen);
    painter->drawText(rect, Qt::AlignCenter, "Cell");
    painter->drawRect(rect); 
}

@SGaist said in QTreeWidget: change font size:

Note that if it's just a question of font, you can set the Qt::FontRole of you model items.

Could you please explain this?
Something like this?:

QFont fff;
fff.setPixelSize(8);
index.model()->data(index, Qt::FontRole).setValue(fff);

[eyllanesc]

Two options:

1. override initStyleOption and don't modify the paint method

void TfDelegate::initStyleOption(QStyleOptionViewItem *option, const QModelIndex &index){
    QStyledItemDelegate::initStyleOption(option, index);
    option->font.setPixelSize(8);
}

Or

2. Use the model

QFont fff;
fff.setPixelSize(8);
index.model()->setData(index, fff,  Qt::FontRole);

[sitesv]

@eyllanesc said in QTreeWidget: change font size:

index.model()->setData(index, fff, Qt::FontRole);

Hi!
Trying to do this in 'paint' event of my delegate.
There is an error:

form_board_delegate.cpp:40:5: error: 'this' argument to member function 'setData' has type 'const QAbstractItemModel', but function is not marked const
qabstractitemmodel.h:192:30: note: 'setData' declared here

I'm supposed that this is valid only for QTreView, not for QTreeWidget. Right?

[mrjj]

@sitesv
Hi
It also works with *Widget version.
Just set on the item and not model.

      auto item = new QTreeWidgetItem(ui->treeWidget);
      QFont font;
      font.setPixelSize(8);
      item->setData(0,Qt::FontRole,font);
      item->setText(0,"MUHA");
      ui->treeWidget->addTopLevelItem(item);

[sitesv]

@eyllanesc said in QTreeWidget: change font size:

> Two options:
> 
> 1. override initStyleOption and don't modify the paint method
> 
> void TfDelegate::initStyleOption(QStyleOptionViewItem *option, const QModelIndex &index){
>     QStyledItemDelegate::initStyleOption(option, index);
>     option->font.setPixelSize(8);
> }

Not working for me,

@mrjj said in QTreeWidget: change font size:

auto item = new QTreeWidgetItem(ui->treeWidget);
QFont font;
font.setPixelSize(8);
item->setData(0,Qt::FontRole,font);
item->setText(0,"MUHA");
ui->treeWidget->addTopLevelItem(item);

Sorry. My case is QTableWidget, not a QTreeWidget.

 newItem = new QTableWidgetItem("");
 newItem->setTextAlignment(Qt::AlignVCenter | Qt::AlignHCenter);

 QFont font;
 font.setPixelSize(8);
 newItem->setText("TEXT");
 newItem->setData(Qt::FontRole, font);

This is also not working in my case.

Maybe something with 'paint' method?

I have only one font size for all items... :(

[eyllanesc]

@sitesv

1. You cannot and should not execute the setData method inside the paint.

2. have you modified the delegate's paint method? If so then you must set the font directly to the QPainter: painter->setFont(fff).

My previous options assume that you are not doing a custom painting (by default the painting is done by QStyle using the attributes of "option").

[sitesv]

@eyllanesc Thank you! It works!