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  4. [SOLVED]How to delete an item from the treeview by droping an item to pushbutton or to an group box

[SOLVED]How to delete an item from the treeview by droping an item to pushbutton or to an group box

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drag and droptreeview
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  • SGaistS SGaist

    Out of curiosity… Why are you creating so many widgets that should allow to delete items from your view using dnd ? It doesn't feel very intuitive nor following the guidelines of major OSs

    RatzzR Offline
    RatzzR Offline
    Ratzz
    wrote on last edited by
    #27

    @SGaist
    Yes , My treeview is in between listview and groupbox . even if the listview items are dragged to the pushbutton_delete its getting deleted. which in my case should not. what is the best way to do ??

    --Alles ist gut.

    1 Reply Last reply
    0
    • SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #28

      Implement it in one of the usual ways:

      • React to the delete or backspace key
      • Have a delete button that will delete the currently selected row/column etc.
      • Have a dedicated column with e.g. a QPushButton to delete the row completely.

      Interested in AI ? www.idiap.ch
      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

      RatzzR 1 Reply Last reply
      0
      • SGaistS SGaist

        Implement it in one of the usual ways:

        • React to the delete or backspace key
        • Have a delete button that will delete the currently selected row/column etc.
        • Have a dedicated column with e.g. a QPushButton to delete the row completely.
        RatzzR Offline
        RatzzR Offline
        Ratzz
        wrote on last edited by
        #29

        @SGaist
        I already have a delete button which deletes entire row.

        --Alles ist gut.

        RatzzR 1 Reply Last reply
        0
        • RatzzR Ratzz

          @SGaist
          I already have a delete button which deletes entire row.

          RatzzR Offline
          RatzzR Offline
          Ratzz
          wrote on last edited by
          #30

          @mrjj
          The code you shared is working (group box).

          --Alles ist gut.

          mrjjM 1 Reply Last reply
          0
          • RatzzR Ratzz

            @mrjj
            The code you shared is working (group box).

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #31

            @Ratzz
            Ok. super.

            RatzzR 1 Reply Last reply
            0
            • mrjjM mrjj

              @Ratzz
              Ok. super.

              RatzzR Offline
              RatzzR Offline
              Ratzz
              wrote on last edited by
              #32

              @mrjj
              But now i can drag items from treeview as well as listview to pushbutton and groupbox. But i do not want the user to allow listview items to dragged to pushbutton/groupbox

              --Alles ist gut.

              mrjjM 1 Reply Last reply
              0
              • RatzzR Ratzz

                @mrjj
                But now i can drag items from treeview as well as listview to pushbutton and groupbox. But i do not want the user to allow listview items to dragged to pushbutton/groupbox

                mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by
                #33

                @Ratzz
                Hmm maybe you can check with
                sender();
                in dragEnterEvent
                and if its the not a Treeview then reject the drop

                like

                QTreeView* theone= dynamic_cast<QTreeView*>(sender());
                   if( theone!= NULL ) 
                   { 
                      event->acceptProposedAction();
                   }
                
                RatzzR 1 Reply Last reply
                0
                • mrjjM mrjj

                  @Ratzz
                  Hmm maybe you can check with
                  sender();
                  in dragEnterEvent
                  and if its the not a Treeview then reject the drop

                  like

                  QTreeView* theone= dynamic_cast<QTreeView*>(sender());
                     if( theone!= NULL ) 
                     { 
                        event->acceptProposedAction();
                     }
                  
                  RatzzR Offline
                  RatzzR Offline
                  Ratzz
                  wrote on last edited by
                  #34

                  @mrjj
                  I do not have dragEnterEvent event yet! . we have a custom event using dropMimeData .

                  --Alles ist gut.

                  mrjjM 1 Reply Last reply
                  0
                  • RatzzR Ratzz

                    @mrjj
                    I do not have dragEnterEvent event yet! . we have a custom event using dropMimeData .

                    mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by mrjj
                    #35

                    @Ratzz
                    how does this custom event look like ?

                    and its not an options just to disable Drag from listview?

                    RatzzR 1 Reply Last reply
                    0
                    • mrjjM mrjj

                      @Ratzz
                      how does this custom event look like ?

                      and its not an options just to disable Drag from listview?

                      RatzzR Offline
                      RatzzR Offline
                      Ratzz
                      wrote on last edited by Ratzz
                      #36

                      @mrjj
                      All drag drop events are handled in this. I am not aware how Bec, previous programmer has done it.

                      bool MessageModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent)
                      {
                          if(action == Qt::CopyAction)
                          {
                      //        QStringList format = data->formats();
                              QByteArray encodedData = data->data("application/x-qabstractitemmodeldatalist");
                              QDataStream stream(&encodedData, QIODevice::ReadOnly);
                              QMap<int,  QVariant> roleDataMap;
                      //        roleDataMap.setInsertInOrder(true);
                              QMap<int, QString> sortMsgs;
                      
                              while (!stream.atEnd())
                              {
                                  int row, col;
                                  stream >> row >> col >> roleDataMap;
                                  QString tmp = roleDataMap.value(0).toString();
                                  //MsgId1.append(tmp);
                                  sortMsgs.insert(row,tmp);
                              }
                              QList < QString > MsgId1 = sortMsgs.values();
                      
                              if(parent.parent().isValid() && !parent.parent().parent().isValid())
                              {
                                  QStandardItemModel::dropMimeData(data,action,row,column,parent);
                                  emit addFrameMessageIds(parent.row(), -1, MsgId1);
                                  return true;
                              }
                              if(parent.parent().parent().isValid() && column == -1)
                              {
                                  QStandardItemModel::dropMimeData(data,action,parent.row() +1,column,parent.parent());
                                  emit addFrameMessageIds(parent.parent().row(),parent.row() +1, MsgId1);
                                  return true;
                              }
                              if(parent.parent().parent().isValid() && column == 0)
                              {
                                  QStandardItemModel::dropMimeData(data,action,row,column,parent);
                                  emit addFrameMessageIds(parent.row(), row, MsgId1);
                                  return true;
                              }
                          }
                          else if(action == Qt::MoveAction)
                          {
                              if(!parent.isValid())
                              {
                                  return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                              }
                              if(indexesLocal.parent().parent().isValid() && !parent.parent().isValid() && column == -1)
                              {
                                  //Msg is dropped on major frame
                                  return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                              }
                              if(indexesLocal.parent().parent().isValid() && !parent.parent().parent().isValid() && column == -1)
                              {
                                  //Msg is dropped on minor frame
                                  if(indexesLocal.parent().row() != parent.row())
                                  {
                                      QStandardItemModel::dropMimeData(data,action,row,column,parent);
                                      emit moveFrameMessageIds(indexesLocal.parent().row(),parent.row(),indexesLocal.row(),-1);
                                      return true;
                                  }
                                  else
                                  {
                                      QStandardItemModel::dropMimeData(data,action, 0 ,column,parent);
                                      emit moveFrameMessageIds(indexesLocal.parent().row(),parent.row(),indexesLocal.row(),0);
                                      return true;
                                  }
                              }
                              if(indexesLocal.parent().parent().isValid() && parent.parent().parent().isValid() && column == -1)
                              {
                                  //      Msg is dropped on another msg
                                  QStandardItemModel::dropMimeData(data,action,parent.row()+1,column,parent.parent());
                                  emit moveFrameMessageIds(indexesLocal.parent().row(),parent.parent().row(),indexesLocal.row(),parent.row()+1);
                                  return true;
                              }
                              if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && !parent.parent().isValid() && column == -1)
                              {
                                  //      Minor frame is dropped on Major frame
                                  QStandardItemModel::dropMimeData(data,action,0,indexesLocal.column(),indexesLocal.parent());
                                  emit moveFrame(indexesLocal.row(),0);
                                  return true;
                              }
                              if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && parent.parent().isValid() && !(parent.parent().parent().isValid()) && column == -1)
                              {
                                  // Minor frame is dropped on another minor frame
                                  int pre = indexesLocal.row();
                                  int cur = parent.row();
                                  QStandardItemModel::dropMimeData(data,action,parent.row()+1,column,parent.parent());
                                  emit moveFrame(indexesLocal.row(),parent.row());
                                  return true;
                              }
                              if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && parent.parent().parent().isValid() && column == -1)
                              {
                                  return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                  //      Minor frame is dropped on msg
                              }
                              if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && !parent.parent().isValid() && column == 0)
                              {
                                  QStandardItemModel::dropMimeData(data,action,row,indexesLocal.column(),indexesLocal.parent());
                                  emit moveFrame(indexesLocal.row(),row);
                                  return true;
                                  //      Minor frame is dropped after minor
                              }
                              if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && !parent.parent().parent().isValid() && column == 0)
                              {
                                  return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                  //      Minor frame is dropped after msg
                              }
                              if(indexesLocal.parent().parent().isValid() && parent.isValid() && !parent.parent().isValid() && column == 0)
                              {
                                  return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                  //      Msg is dropped after minor
                              }
                              if(indexesLocal.parent().parent().isValid() && parent.parent().isValid() && !parent.parent().parent().isValid() && column == 0)
                              {
                                  QStandardItemModel::dropMimeData(data,action,row,parent.column(),parent);
                                  emit moveFrameMessageIds(indexesLocal.parent().row(),parent.row(),indexesLocal.row(),row);
                                  return true;
                                  //      Msg is dropped after msg
                              }
                      }
                      }
                      

                      And one more thing. If i drag items to pushbutton/group box the listview count is not getting updated.. ex:if i have 5 items and drag 1 item to pushbutton_delete then the count will be 5 . if i manually press delete button now then the list is getting updated to 3.

                      --Alles ist gut.

                      mrjjM 1 Reply Last reply
                      0
                      • RatzzR Ratzz

                        @mrjj
                        All drag drop events are handled in this. I am not aware how Bec, previous programmer has done it.

                        bool MessageModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent)
                        {
                            if(action == Qt::CopyAction)
                            {
                        //        QStringList format = data->formats();
                                QByteArray encodedData = data->data("application/x-qabstractitemmodeldatalist");
                                QDataStream stream(&encodedData, QIODevice::ReadOnly);
                                QMap<int,  QVariant> roleDataMap;
                        //        roleDataMap.setInsertInOrder(true);
                                QMap<int, QString> sortMsgs;
                        
                                while (!stream.atEnd())
                                {
                                    int row, col;
                                    stream >> row >> col >> roleDataMap;
                                    QString tmp = roleDataMap.value(0).toString();
                                    //MsgId1.append(tmp);
                                    sortMsgs.insert(row,tmp);
                                }
                                QList < QString > MsgId1 = sortMsgs.values();
                        
                                if(parent.parent().isValid() && !parent.parent().parent().isValid())
                                {
                                    QStandardItemModel::dropMimeData(data,action,row,column,parent);
                                    emit addFrameMessageIds(parent.row(), -1, MsgId1);
                                    return true;
                                }
                                if(parent.parent().parent().isValid() && column == -1)
                                {
                                    QStandardItemModel::dropMimeData(data,action,parent.row() +1,column,parent.parent());
                                    emit addFrameMessageIds(parent.parent().row(),parent.row() +1, MsgId1);
                                    return true;
                                }
                                if(parent.parent().parent().isValid() && column == 0)
                                {
                                    QStandardItemModel::dropMimeData(data,action,row,column,parent);
                                    emit addFrameMessageIds(parent.row(), row, MsgId1);
                                    return true;
                                }
                            }
                            else if(action == Qt::MoveAction)
                            {
                                if(!parent.isValid())
                                {
                                    return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                }
                                if(indexesLocal.parent().parent().isValid() && !parent.parent().isValid() && column == -1)
                                {
                                    //Msg is dropped on major frame
                                    return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                }
                                if(indexesLocal.parent().parent().isValid() && !parent.parent().parent().isValid() && column == -1)
                                {
                                    //Msg is dropped on minor frame
                                    if(indexesLocal.parent().row() != parent.row())
                                    {
                                        QStandardItemModel::dropMimeData(data,action,row,column,parent);
                                        emit moveFrameMessageIds(indexesLocal.parent().row(),parent.row(),indexesLocal.row(),-1);
                                        return true;
                                    }
                                    else
                                    {
                                        QStandardItemModel::dropMimeData(data,action, 0 ,column,parent);
                                        emit moveFrameMessageIds(indexesLocal.parent().row(),parent.row(),indexesLocal.row(),0);
                                        return true;
                                    }
                                }
                                if(indexesLocal.parent().parent().isValid() && parent.parent().parent().isValid() && column == -1)
                                {
                                    //      Msg is dropped on another msg
                                    QStandardItemModel::dropMimeData(data,action,parent.row()+1,column,parent.parent());
                                    emit moveFrameMessageIds(indexesLocal.parent().row(),parent.parent().row(),indexesLocal.row(),parent.row()+1);
                                    return true;
                                }
                                if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && !parent.parent().isValid() && column == -1)
                                {
                                    //      Minor frame is dropped on Major frame
                                    QStandardItemModel::dropMimeData(data,action,0,indexesLocal.column(),indexesLocal.parent());
                                    emit moveFrame(indexesLocal.row(),0);
                                    return true;
                                }
                                if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && parent.parent().isValid() && !(parent.parent().parent().isValid()) && column == -1)
                                {
                                    // Minor frame is dropped on another minor frame
                                    int pre = indexesLocal.row();
                                    int cur = parent.row();
                                    QStandardItemModel::dropMimeData(data,action,parent.row()+1,column,parent.parent());
                                    emit moveFrame(indexesLocal.row(),parent.row());
                                    return true;
                                }
                                if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && parent.parent().parent().isValid() && column == -1)
                                {
                                    return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                    //      Minor frame is dropped on msg
                                }
                                if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && !parent.parent().isValid() && column == 0)
                                {
                                    QStandardItemModel::dropMimeData(data,action,row,indexesLocal.column(),indexesLocal.parent());
                                    emit moveFrame(indexesLocal.row(),row);
                                    return true;
                                    //      Minor frame is dropped after minor
                                }
                                if(indexesLocal.parent().isValid() && !(indexesLocal.parent().parent().isValid()) && !parent.parent().parent().isValid() && column == 0)
                                {
                                    return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                    //      Minor frame is dropped after msg
                                }
                                if(indexesLocal.parent().parent().isValid() && parent.isValid() && !parent.parent().isValid() && column == 0)
                                {
                                    return QStandardItemModel::dropMimeData(data,action,indexesLocal.row(),indexesLocal.column(),indexesLocal.parent());
                                    //      Msg is dropped after minor
                                }
                                if(indexesLocal.parent().parent().isValid() && parent.parent().isValid() && !parent.parent().parent().isValid() && column == 0)
                                {
                                    QStandardItemModel::dropMimeData(data,action,row,parent.column(),parent);
                                    emit moveFrameMessageIds(indexesLocal.parent().row(),parent.row(),indexesLocal.row(),row);
                                    return true;
                                    //      Msg is dropped after msg
                                }
                        }
                        }
                        

                        And one more thing. If i drag items to pushbutton/group box the listview count is not getting updated.. ex:if i have 5 items and drag 1 item to pushbutton_delete then the count will be 5 . if i manually press delete button now then the list is getting updated to 3.

                        mrjjM Offline
                        mrjjM Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on last edited by
                        #37

                        @Ratzz said:

                        But i do not want the user to allow listview items to dragged to pushbutton/groupbox

                        So why can you not check there ?

                        also
                        http://doc.qt.io/qt-5/qtreewidget.html#dropMimeData
                        Seems to be when something is dropped on Tree and im confused what it has to do with the
                        Groupbox ?

                        RatzzR 1 Reply Last reply
                        0
                        • mrjjM mrjj

                          @Ratzz said:

                          But i do not want the user to allow listview items to dragged to pushbutton/groupbox

                          So why can you not check there ?

                          also
                          http://doc.qt.io/qt-5/qtreewidget.html#dropMimeData
                          Seems to be when something is dropped on Tree and im confused what it has to do with the
                          Groupbox ?

                          RatzzR Offline
                          RatzzR Offline
                          Ratzz
                          wrote on last edited by
                          #38

                          @mrjj
                          Since the groupbox is deletes item as you suggested it also deletes listview items when dragged.

                          --Alles ist gut.

                          mrjjM 1 Reply Last reply
                          0
                          • RatzzR Ratzz

                            @mrjj
                            Since the groupbox is deletes item as you suggested it also deletes listview items when dragged.

                            mrjjM Offline
                            mrjjM Offline
                            mrjj
                            Lifetime Qt Champion
                            wrote on last edited by
                            #39

                            @Ratzz
                            And the DragGBox do have
                            void dragEnterEvent(QDragEnterEvent* event) {
                            event->acceptProposedAction();
                            }

                            So why cant you just check that sender if the accepted one and then acccept or if not then
                            reject the drop?

                            RatzzR 1 Reply Last reply
                            0
                            • mrjjM mrjj

                              @Ratzz
                              And the DragGBox do have
                              void dragEnterEvent(QDragEnterEvent* event) {
                              event->acceptProposedAction();
                              }

                              So why cant you just check that sender if the accepted one and then acccept or if not then
                              reject the drop?

                              RatzzR Offline
                              RatzzR Offline
                              Ratzz
                              wrote on last edited by
                              #40

                              @mrjj
                              dragEnterEvent shoud be used for main class?

                              --Alles ist gut.

                              mrjjM 1 Reply Last reply
                              0
                              • RatzzR Ratzz

                                @mrjj
                                dragEnterEvent shoud be used for main class?

                                mrjjM Offline
                                mrjjM Offline
                                mrjj
                                Lifetime Qt Champion
                                wrote on last edited by
                                #41

                                @mrjj said:
                                For the DropGroupBox class.
                                I assume you use that one?

                                RatzzR 1 Reply Last reply
                                0
                                • mrjjM mrjj

                                  @mrjj said:
                                  For the DropGroupBox class.
                                  I assume you use that one?

                                  RatzzR Offline
                                  RatzzR Offline
                                  Ratzz
                                  wrote on last edited by Ratzz
                                  #42

                                  @mrjj
                                  yes i have used this one.
                                  Since its different class how to pull the sender to it?
                                  can you just drop me some piece of code.

                                  --Alles ist gut.

                                  1 Reply Last reply
                                  0
                                  • ? Guest
                                    RatzzR Offline
                                    RatzzR Offline
                                    Ratzz
                                    wrote on last edited by
                                    #43

                                    @mrjj
                                    Not it does not allow even the treeview items to drop

                                    --Alles ist gut.

                                    1 Reply Last reply
                                    0
                                    • ? Guest
                                      mrjjM Offline
                                      mrjjM Offline
                                      mrjj
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #44

                                      STOP
                                      sender() not working for events it seems.
                                      So cannot work.
                                      So its a no go.

                                      RatzzR 1 Reply Last reply
                                      0
                                      • mrjjM mrjj

                                        STOP
                                        sender() not working for events it seems.
                                        So cannot work.
                                        So its a no go.

                                        RatzzR Offline
                                        RatzzR Offline
                                        Ratzz
                                        wrote on last edited by
                                        #45

                                        @mrjj
                                        ok fine.. what next?!

                                        --Alles ist gut.

                                        mrjjM 1 Reply Last reply
                                        0
                                        • RatzzR Ratzz

                                          @mrjj
                                          ok fine.. what next?!

                                          mrjjM Offline
                                          mrjjM Offline
                                          mrjj
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #46

                                          @Ratzz
                                          you can use
                                          QWidget * QDropEvent::source() const

                                          read here
                                          http://doc.qt.io/qt-5.5/qdropevent.html#source

                                          RatzzR 1 Reply Last reply
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