Thanks, mrjj!
That's it!

Merry christmas

@JonB
This code is a small example to find solution.
In my real project i need to show tree with different items and nested trees.

@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

A late reply, but it looks like those elements are different in that they don't have children. Have you checked that you don't have a style with

QTreeView::item:!has-children { padding: ... }

defined anywhere which could be overriding the style when applied at the branch level?

treeWidget->model()->removeRows(0,treeWidget->model()->rowCount()); clears the widget of all items and deletes them freeing the memory (see the sources if you don't believe me). Be aware that it's difficult to assess memory usage live in debug mode as the OS might keep the memory allocated for a while after you call delete

You can use either QTreeWidget, QTableWidget, QTreeView+QStandardItemModel, QTableView+QStandardItemModel, QTreeView+QAbstactTableModel subclass, QTableView+QAbstactTableModel subclass for what you are trying to do.

I would go with a QT*View+QStandardItemModel (tree or table doesn't matter).

The functionalities you describe are:

only some columns will be editable

use QStandardItem::setFlag

Entering a value in the cents column (a logarithmic measure of frequency) will change the value in the hertz column, and vice versa

connect a slot to QStandardItemModel::dataChanged signal

There will be a button next to the table to add an additional note to the scale

connect a slot that calls QStandardItemModel::insertRows to the QPushButton::clicked signal

Hi,

You should share the code of your MyWidgetTree class. That way it will make things easier to analyse.

I was always searching at the wrong place.

The blue hue wasn't a problem of the style, it was a problem of the icon. Here is the solution:

for all icons

m_clientIcon.normal.addFile("plugins\\qtTsOverlay\\client.png");

add this

m_clientIcon.normal.addFile("plugins\\qtTsOverlay\\client.png", QSize(), QIcon::Selected);

Again, thanks a lot for your help :)

@mrjj Thank you for your time. I'll investigate further and report if I find any. If anyone else knows anything of this inconsistent behavior please do reply.

Depending on your needs you might be interested by DevMachines's QTitanRibbon which seems to be doing what you want. Note that it's a commercial product.

What exactly are you trying to achieve with putting the scroll bar to the left ?

There are already several applications written in QML for desktop. It really depends on what you want to do.

With my new installation Creator 3.6.0 (new version) and Qt 5.5.1 (same version as before) it works now.

You might be getting the value before it has been transferred to the model

Hi
You can try with eventfilter on the QTreeWidget.

After disabling a whole bunch of Windows policies suddenly I get the desired behaviour.... that is surprising. I still don't know the root cause, but I'll postpone looking further until the problem reappears

It turns out the style was overwritten by a style appearing at the end of the stylesheet...... bummer

That worked. I knew it had to be something simple. Thanks.

As it turned out, one must explicitly say QTreeView::indicator:unchecked in order to set the general settings like background color for this checkbox. That was a bit surprising, as this is not needed for instance for QCheckbox::indicator or QGroupBox::indicator, but the solution is now here for posterity

I figured it out, that information is the header of the QTreeWidget. So, the code to extract this value from within a QTreeWidgetItem is:

self.treeWidget().header().sortIndicatorOrder()

and this you can check for being equal to Qt.DescendingOrder (or Qt.AscendingOrder if you prefer).

Hi,

You are looking for QTreeWidget::setCurrentItem

@SGaist Thank you once again!
Now, I can manage to display the folder list inside the stacked widget page using QTreeView + QFileSystemModel combo!

@Bart
Hi,
please
put

QHash<QString, QTreeWidgetItem * > Parents;

outside the for loop.
Also,
you say

if(blades.contains(ArraySet1[i][0]))

Should that not be Parents?
Anyway, when Contains is true, you do not create a new QTreeWidgetItem but instead use the one you store in the
hash list. that way you will connect to the same Parent (the first one) when you see the same name again.
We use the list to keep track of ParentName, and the QTreeWidgetItem that we created with that name.
so

if(blades.contains(ArraySet1[i][0])) { QTreeWidgetItem *y = new QTreeWidgetItem(); y>setText(0,ArraySet1[i][1]); x->addChild(y); <----------------- x here should be the parent you stored in the hash list }

becomes

if(Parents.contains(ArraySet1[i][0])) { QTreeWidgetItem *NewChild = new QTreeWidgetItem(); NewChild>setText(0,ArraySet1[i][1]); QTreeWidgetItem *StoredParent =Parents.value(ArraySet1[i][0]); StoredParent ->addChild(NewChild) } else { // create the new parent and store in list QTreeWidgetItem *x = new QTreeWidgetItem(ui->treeWidget); x->setText(0,ArraySet1[i][0]); ui->treeWidget->addTopLevelItem(x); Parents->Insert( ArraySet1[i][0], x ); // store our parent under that name QTreeWidgetItem *y = new QTreeWidgetItem(); y->setText(0,ArraySet1[i][1]); x->addChild(y); QTreeWidgetItem *z = new QTreeWidgetItem(); z->setText(0,ArraySet1[i][2]); y->addChild(z); l }

something like that. Hope it makes sense.
ps. did not try to compile so might be syntax errors.

Looping is not slow, what takes time is string comparison, cause you basically do brute force string searching.
As Chris mentioned in normal circumstances this can't lag your GUI.

But if you fill your tree with huge number of data there might be a few performance problems.
Possible solutions:

a) QTreeView with custom model may be faster for multiple reasons including no need for frequent memory allocation and reduced data duplication.

b) Consider using additional data structure ( temporary or permanent) to speed up large modifications. Example will be usage of hash table which will speed up your search. But keep in mind that maintenance of such data structure may actually make it even slower depending on your usage case.

@SGaist Oh, OK... Then I'll implement that too and see how it goes. Thanks.