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QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once

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  • jsulmJ jsulm

    @Taz742 said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

    then I close tab

    I guess if you close the tab then the tab and its content (tree view) are deleted?

    Taz742T Offline
    Taz742T Offline
    Taz742
    wrote on last edited by
    #10

    @jsulm
    First click on my button
    alt text

    Result is good, i have 2 treeitem:
    alt text

    now close this tab and click again my button and insert tab, result is:
    alt text

    Do what you want.

    jsulmJ 1 Reply Last reply
    0
    • Taz742T Taz742

      @jsulm
      First click on my button
      alt text

      Result is good, i have 2 treeitem:
      alt text

      now close this tab and click again my button and insert tab, result is:
      alt text

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #11

      @Taz742 You should debug your app to see what happens.

      https://forum.qt.io/topic/113070/qt-code-of-conduct

      Taz742T 1 Reply Last reply
      0
      • jsulmJ jsulm

        @Taz742 You should debug your app to see what happens.

        Taz742T Offline
        Taz742T Offline
        Taz742
        wrote on last edited by
        #12

        @jsulm
        Of course i tryed...

            for (auto it = items.begin(); it != items.end(); it++) {
                ui->treeWidget->addTopLevelItem(it.value());
                it.value()->setExpanded(true);
            }
        

        Its entered in my loop, everything is done without a problem but i can't see my treeitems.
        Also i tryed

        qDebug() << ui->treeWidget->topLevelItemsCount();
        

        after end loop, and result is 0.

        Do what you want.

        1 Reply Last reply
        0
        • GeekOwLG Offline
          GeekOwLG Offline
          GeekOwL
          wrote on last edited by
          #13

          Here are you sure your wdgTemplate is nullptr after closing it ? or when close is activated are you sure you handled to not delete the closed tab and its data ?

           if (wdgTemplate) {
                  ui->tabWidget->setCurrentWidget(wdgTemplate);
                  return;
              }
          
          Taz742T 1 Reply Last reply
          0
          • GeekOwLG GeekOwL

            Here are you sure your wdgTemplate is nullptr after closing it ? or when close is activated are you sure you handled to not delete the closed tab and its data ?

             if (wdgTemplate) {
                    ui->tabWidget->setCurrentWidget(wdgTemplate);
                    return;
                }
            
            Taz742T Offline
            Taz742T Offline
            Taz742
            wrote on last edited by Taz742
            #14

            @GeekOwL said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

            Here are you sure your wdgTemplate is nullptr after closing it ?

            Yes.

                QObject::connect(this->ui->tabWidget, &QTabWidget::tabCloseRequested, this, [=](int index) {
                    if (index != ui->tabWidget->indexOf(dlg)) {
                        if(ui->tabWidget->widget(index) == dlgRep) {
                            ui->tabWidget->removeTab(index);
                            dlgRep = NULL;
                        } else if (ui->tabWidget->widget(index) == wdgTemplate) {
                            ui->tabWidget->removeTab(index);
                            wdgTemplate = NULL;
                        }
                    }
                });
            

            @GeekOwL said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

            or when close is activated are you sure you handled to not delete the closed tab and its data

            I dont know... I have no answer to this question.

            Do what you want.

            Taz742T 1 Reply Last reply
            0
            • Taz742T Taz742

              @GeekOwL said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

              Here are you sure your wdgTemplate is nullptr after closing it ?

              Yes.

                  QObject::connect(this->ui->tabWidget, &QTabWidget::tabCloseRequested, this, [=](int index) {
                      if (index != ui->tabWidget->indexOf(dlg)) {
                          if(ui->tabWidget->widget(index) == dlgRep) {
                              ui->tabWidget->removeTab(index);
                              dlgRep = NULL;
                          } else if (ui->tabWidget->widget(index) == wdgTemplate) {
                              ui->tabWidget->removeTab(index);
                              wdgTemplate = NULL;
                          }
                      }
                  });
              

              @GeekOwL said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

              or when close is activated are you sure you handled to not delete the closed tab and its data

              I dont know... I have no answer to this question.

              Taz742T Offline
              Taz742T Offline
              Taz742
              wrote on last edited by
              #15

              I replace my code, i create QtreeWidgetItem only constructor, i have a following code and its work fine:

              QMap<int, ForTree> &items = globalall->tree;
              auto it = items.begin();
              auto &&topItem = new MyTree(it.value().Name, it.value().UID, it.value().Pause);
              topItem->setExpanded(true);
              ui->treeWidget->addTopLevelItem(topItem);
              this->mpTree[it.key()] = topItem;
              
              it++;
              for (; it != items.end(); it++) {
                  MyTree *m_item = new MyTree(it.value().Name, it.value().UID, it.value().Pause);
                  m_item->setExpanded(true);
                  this->mpTree[it.value().ParentUID]->addChild(m_item);
                  this->mpTree[it.key()] = m_item;
              }
              

              MyTree is a my class, sub class of QTreeWidgetItem:

              MyTree::MyTree(QVariant value, int UID, bool checked, QTreeWidgetItem *parent) : QTreeWidgetItem(parent)
              {
                  this->m_value = value;
                  this->m_parent = static_cast<MyTree*>(parent);
                  this->m_UID = UID;
                  this->m_checked = checked;
              
                  this->setData(0, Qt::EditRole, value);
                  this->setIcon(0, QIcon(":/SMSicons/folder.png"));
                  this->setCheckState(0, (checked ^ 1) ? Qt::Checked : Qt::Unchecked);
              }
              
              • But I still wonder what was the problem?

              • If my treeItems were destroyed with the tree, why i have items in my QMap<> ?

              Do what you want.

              jsulmJ 1 Reply Last reply
              0
              • Taz742T Taz742

                I replace my code, i create QtreeWidgetItem only constructor, i have a following code and its work fine:

                QMap<int, ForTree> &items = globalall->tree;
                auto it = items.begin();
                auto &&topItem = new MyTree(it.value().Name, it.value().UID, it.value().Pause);
                topItem->setExpanded(true);
                ui->treeWidget->addTopLevelItem(topItem);
                this->mpTree[it.key()] = topItem;
                
                it++;
                for (; it != items.end(); it++) {
                    MyTree *m_item = new MyTree(it.value().Name, it.value().UID, it.value().Pause);
                    m_item->setExpanded(true);
                    this->mpTree[it.value().ParentUID]->addChild(m_item);
                    this->mpTree[it.key()] = m_item;
                }
                

                MyTree is a my class, sub class of QTreeWidgetItem:

                MyTree::MyTree(QVariant value, int UID, bool checked, QTreeWidgetItem *parent) : QTreeWidgetItem(parent)
                {
                    this->m_value = value;
                    this->m_parent = static_cast<MyTree*>(parent);
                    this->m_UID = UID;
                    this->m_checked = checked;
                
                    this->setData(0, Qt::EditRole, value);
                    this->setIcon(0, QIcon(":/SMSicons/folder.png"));
                    this->setCheckState(0, (checked ^ 1) ? Qt::Checked : Qt::Unchecked);
                }
                
                • But I still wonder what was the problem?

                • If my treeItems were destroyed with the tree, why i have items in my QMap<> ?

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #16

                @Taz742 said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

                MyTree *m_item = new MyTree(it.value().Name, it.value().UID, it.value().Pause);

                You don't provide a parent and I'm not sure the QTreeWidget takes the ownership of the children if you add them. If not then it would explain why they are still there.

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                Taz742T 1 Reply Last reply
                0
                • jsulmJ jsulm

                  @Taz742 said in QTreeWidget from my QMap<int, QTreeWidgetItem*> populate only once:

                  MyTree *m_item = new MyTree(it.value().Name, it.value().UID, it.value().Pause);

                  You don't provide a parent and I'm not sure the QTreeWidget takes the ownership of the children if you add them. If not then it would explain why they are still there.

                  Taz742T Offline
                  Taz742T Offline
                  Taz742
                  wrote on last edited by
                  #17

                  @jsulm
                  Please leave it for a while.
                  Think about the problem only, because if i use QTreeWidgetItem and not MyTree i have the same problem..

                  Do what you want.

                  1 Reply Last reply
                  0
                  • mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by
                    #18

                    Hi
                    I was thinking:

                    If the TreeWidget didnt not take ownership of the items, then any normal use case would leak.
                    So if the treewidget is deleted, it will delete its items too.

                    If you have a QMap with pointers to the items.
                    You map will still have the items * pointer but now they point to deleted QtreeWidgetItem (child)
                    if used once/given to a TreeWidget and this TreeWidget gets deleted.

                    Taz742T 1 Reply Last reply
                    1
                    • mrjjM mrjj

                      Hi
                      I was thinking:

                      If the TreeWidget didnt not take ownership of the items, then any normal use case would leak.
                      So if the treewidget is deleted, it will delete its items too.

                      If you have a QMap with pointers to the items.
                      You map will still have the items * pointer but now they point to deleted QtreeWidgetItem (child)
                      if used once/given to a TreeWidget and this TreeWidget gets deleted.

                      Taz742T Offline
                      Taz742T Offline
                      Taz742
                      wrote on last edited by
                      #19

                      @mrjj
                      Yes supposedly.

                      Do what you want.

                      1 Reply Last reply
                      0

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