Configuring checkbox when using QTreeWidget

[MATTK]

Hello, I was trying to make something like this using PyQt 5.11.2 and Qt Designer.

So I marked the "UserCheckable" flag to expect a checkbox next to items "XXX", "YYY", and "ZZZ".

However, the checkboxes don't appear.
Is it not possible to configure the items to have checkboxes with Qt Designer?
Do I have to type the code "ItemIsUserCheckable" manually?

-Regards

[SGaist]

Hi,

After a quick test, it seems to you have to use setCheckState(Qt::Unchecked) or setCheckState(Qt::Checked) if you want to have the checkbox appearing in your GUI.

[MATTK]

Thanks for your reply, SGaist.

I wish to solve this using the Qt Designer.
I'm using Qt Designer 5.9.1.
Then, is this a bug or a known issue from Qt Designer?

-Regards

[VRonin]

@MATTK said in Configuring checkbox when using QTreeWidget:

is this a bug or a known issue from Qt Designer?

No, it's 100% intended behaviour. the condition is checked here

You have 2 options:

• set the Qt::CheckStateRole for the indexes you want to have a checkbox. In your widget constructor you'd call something like setUnchecked(ui->treeWidget->model());

void setUnchecked(QAbstractItemModel* model, const QModelIndex& parent = QModelIndex()){
    if(!model)
        return;
    for(int i=0, maxRow=model->rowCount(parent);i<maxRow;++i){
        for(int j=0, maxCol=model->columnCount(parent);j<maxCol;++j){
            const QModelIndex currIdx = model->index(i,j,parent);
            model->setData(currIdx,Qt::Unchecked,Qt::CheckStateRole);
            if(model->hasChildren(currIdx))
                setUnchecked(model,currIdx);
        }
    }
}

• subclass the delegate to check the flag instead of Qt::CheckStateRole and call something like ui->treeWidget->setItemDelegate(new CheckFlagDelegate(this)); in your widget constructor

class CheckFlagDelegate : public QStyledItemDelegate{
    Q_OBJECT
    Q_DISABLE_COPY(CheckFlagDelegate)
public:
    explicit CheckFlagDelegate(QObject* parent = Q_NULLPTR) : QStyledItemDelegate(parent){}
protected:
    void initStyleOption(QStyleOptionViewItem *option, const QModelIndex &index) const Q_DECL_OVERRIDE{
        QStyledItemDelegate::initStyleOption(option,index);
        if(index.model()->flags(index) & Qt::ItemIsUserCheckable)
            option->features |= QStyleOptionViewItem::HasCheckIndicator;
    }
};

Since the functionality is defined in a QObject (the delegate) and not in a QWidget this is not something designer can and probably ever will manage