QTreeWidget QCheckBox signal itemChanged for root

Lior

Hi,
I'm want to implement tree of checkbox.
I used tree widget.

when some root is change, I want to update all the childes,
but when I update some child check state, the signal fire again.

when one child is changed , it work partly ok, when i need to change to root (let say if all is selected and i uncheck one child so i need to uncheck the root and i got the same problem)

is there is a good example or explain a good way to implement it??

Axel Spoerl

Updating the check state will always fire the signal, unless you block signals before programmatic update and restore the original state afterwards. You can do that manually or with a signal blocker, see here.

Lior

@Axel-Spoerl said in QTreeWidget QCheckBox signal itemChanged for root:

u can do that m

can you offer a solution to this fetcher? (tree of checkboxes)
when you check/uncheck root - update all the children as the root
if a child is checked and it's the last that not checked - set the root as checked (and the same logic for unchecking).

Axel Spoerl

@Lior
What do you mean by „this fetcher“?
Post your code and the community will look what can be improved.

Lior

Hi,
Here is the example code. it is quick and dirty only for learning this, I will rewrite it,
the main objective is to hold a tree of checkboxes,

when a checkbox is checked or unchecked - do something
if a root is checked or unchecked - update all the children
if all the children are checked, update the root to be checked
if at least one of the children is not checked, the root is not checked

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QPushButton>

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    ui->treeWidget->setColumnCount(1);

    // set headers
    QStringList label ;
    label << "FileName";//<< "FilePath"<< "Widget";
    ui->treeWidget->setHeaderLabels(label);

    QTreeWidgetItem *root = new QTreeWidgetItem(ui->treeWidget);
    root->setText(0,"RootFile");
    root->setCheckState(0, Qt::Unchecked);
    ui->treeWidget->addTopLevelItem(root);

    addItem(0, "c" + QString::number(1), Qt::Unchecked, root);
    addItem(0, "c" + QString::number(2), Qt::Unchecked, root);
    addItem(0, "c" + QString::number(3), Qt::Unchecked, root);
    addItem(0, "c" + QString::number(4), Qt::Unchecked, root);

}

void MainWindow::addItem(int col, QString name, Qt::CheckState checkedState, QTreeWidgetItem *root)
{
    CPloyPropertiesTreeWidgetItem *child = new CPloyPropertiesTreeWidgetItem();
    child->setText(col,name);
    child->setCheckState(col, checkedState);
    root->addChild(child);
}

MainWindow::~MainWindow()
{
    delete ui;
}


void MainWindow::on_treeWidget_itemChanged(QTreeWidgetItem *item, int column)
{
    bool isRootChanged = item->parent() == nullptr;

    if(!isRootChanged)
    {
        Qt::CheckState cs = item->checkState(column);
        QTreeWidgetItemIterator it(item->parent());
        bool isAll = true;
        ++it; // skip the root
        while (*it)
        {
            // if at least one is different, uncheck the root, otherwise set the root as the child
            if ((*it)->checkState(column) != cs)
            {
                isAll = false;
                break;
            }
            ++it;
        }

        if(isAll)
        {
            item->parent()->setCheckState(column,cs);
        }
        else
        {
            item->parent()->setCheckState(column,Qt::CheckState::Unchecked);
        }
    }

    if(isRootChanged)
    {
        QTreeWidgetItemIterator it(item);
        Qt::CheckState rootCs = item->checkState(column);
        ++it;
        while (*it)
        {
            if ((*it)->checkState(column) != rootCs)
            {
                (*it)->setCheckState(column, rootCs);

            }
            ++it;
        }
    }
    else // child changed
    {
       enableDisableVisablity();
    }
}

void MainWindow::enableDisableVisablity()
{

}