Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. How to reposition cursor to the end of the document without autoscroll
Forum Updated to NodeBB v4.3 + New Features

How to reposition cursor to the end of the document without autoscroll

Scheduled Pinned Locked Moved Unsolved General and Desktop
49 Posts 5 Posters 8.3k Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • jsulmJ jsulm

    @lukutis222 What you are doing does not make sence. If you want to override mousePressEvent in QTextEdit you need to subclass QTextEdit and do it there. Just like you did with QWidget. And then you use your subclass instead of QTextEdit.

    L Offline
    L Offline
    lukutis222
    wrote on last edited by lukutis222
    #24

    @jsulm Yes I understand that but I was wondering if I need to create a seperate class just for QTextEdit so I can override one function? Can I make widget class inherit from QTextEdit and then override it in my widget class if that makes sense?

    jsulmJ 1 Reply Last reply
    0
    • L lukutis222

      @jsulm Yes I understand that but I was wondering if I need to create a seperate class just for QTextEdit so I can override one function? Can I make widget class inherit from QTextEdit and then override it in my widget class if that makes sense?

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #25

      @lukutis222 said in How to reposition cursor to the end of the document without autoscroll:

      I was wondering if I need to create a seperate class just for QTextEdit so I can override one function?

      Yes, this is how subclassing and overriding works.

      "Can I make widget class inherit from QTextEdit and then override it in my widget class if that makes sense?" - not sure what you mean. As I sais: subclass QTextEdit and override in your subclass...

      And please also read what @JonB suggested.

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

      1 Reply Last reply
      1
      • JonBJ JonB

        @lukutis222
        Indeed, because the mouse event goes to the lower-level widget you click on.

        Look at installing an application event filter, or on your Widget, for a convenient way of intercepting all mouse events, regardless of targeted widget: https://doc.qt.io/qt-6/eventsandfilters.html, https://doc.qt.io/qt-6/qobject.html#eventFilter. Otherwsie you will have to subclass and override mousePressEvent for every one of your widgets.

        JonBJ Online
        JonBJ Online
        JonB
        wrote on last edited by JonB
        #26

        @lukutis222

        @JonB said in How to reposition cursor to the end of the document without autoscroll:

        Look at installing an application event filter, or on your Widget, for a convenient way of intercepting all mouse events, regardless of targeted widget: https://doc.qt.io/qt-6/eventsandfilters.html, https://doc.qt.io/qt-6/qobject.html#eventFilter. Otherwsie you will have to subclass and override mousePressEvent for every one of your widgets.

        Should be pretty clear. Or you can ignore it.

        L 1 Reply Last reply
        0
        • JonBJ JonB

          @lukutis222

          @JonB said in How to reposition cursor to the end of the document without autoscroll:

          Look at installing an application event filter, or on your Widget, for a convenient way of intercepting all mouse events, regardless of targeted widget: https://doc.qt.io/qt-6/eventsandfilters.html, https://doc.qt.io/qt-6/qobject.html#eventFilter. Otherwsie you will have to subclass and override mousePressEvent for every one of your widgets.

          Should be pretty clear. Or you can ignore it.

          L Offline
          L Offline
          lukutis222
          wrote on last edited by lukutis222
          #27

          @jsulm @JonB
          JonB I do not ignore and I will definately look into this (eventfilters). I just want to learn first how to correctly override subclass methods because this is very interesting topic for me and very useful to learn. I am still learning C++ and I feel like this is very important to understand (which I struggle to do yet)

          Just for the sake of testing, I have created a class with a QTextEdit base class:

          custom_text_edit.cpp

          #include "custom_text_edit.h"
          
          custom_text_Edit::custom_text_Edit()
          {
          
          }
          
          void custom_text_Edit::mousePressEvent(QMouseEvent *event)
          {
              qDebug("pressed inside qtextedit \n");
          }
          
          

          custom_text_edit.h

          #ifndef CUSTOM_TEXT_EDIT_H
          #define CUSTOM_TEXT_EDIT_H
          
          #include <QTextEdit>
          
          class custom_text_Edit : public QTextEdit
          {
          public:
              custom_text_Edit();
          
          protected:
              void mousePressEvent(QMouseEvent *event) override;
          };
          
          #endif // CUSTOM_TEXT_EDIT_H
          
          

          I create class instance in my main.cpp:

          custom_text_Edit cte;
          

          Is there anything else I am missing? When I click on the QTextEdit widget ( my console), I still cannot trigger the mouseclick event that I just overriden

          jsulmJ JonBJ 2 Replies Last reply
          0
          • L lukutis222

            @jsulm @JonB
            JonB I do not ignore and I will definately look into this (eventfilters). I just want to learn first how to correctly override subclass methods because this is very interesting topic for me and very useful to learn. I am still learning C++ and I feel like this is very important to understand (which I struggle to do yet)

            Just for the sake of testing, I have created a class with a QTextEdit base class:

            custom_text_edit.cpp

            #include "custom_text_edit.h"
            
            custom_text_Edit::custom_text_Edit()
            {
            
            }
            
            void custom_text_Edit::mousePressEvent(QMouseEvent *event)
            {
                qDebug("pressed inside qtextedit \n");
            }
            
            

            custom_text_edit.h

            #ifndef CUSTOM_TEXT_EDIT_H
            #define CUSTOM_TEXT_EDIT_H
            
            #include <QTextEdit>
            
            class custom_text_Edit : public QTextEdit
            {
            public:
                custom_text_Edit();
            
            protected:
                void mousePressEvent(QMouseEvent *event) override;
            };
            
            #endif // CUSTOM_TEXT_EDIT_H
            
            

            I create class instance in my main.cpp:

            custom_text_Edit cte;
            

            Is there anything else I am missing? When I click on the QTextEdit widget ( my console), I still cannot trigger the mouseclick event that I just overriden

            jsulmJ Offline
            jsulmJ Offline
            jsulm
            Lifetime Qt Champion
            wrote on last edited by
            #28

            @lukutis222 said in How to reposition cursor to the end of the document without autoscroll:

            Is there anything else I am missing?

            Yes, you are still using QTextEdit in your UI. You need to replace it with your custom_text_Edit.

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

            1 Reply Last reply
            1
            • L lukutis222

              @jsulm @JonB
              JonB I do not ignore and I will definately look into this (eventfilters). I just want to learn first how to correctly override subclass methods because this is very interesting topic for me and very useful to learn. I am still learning C++ and I feel like this is very important to understand (which I struggle to do yet)

              Just for the sake of testing, I have created a class with a QTextEdit base class:

              custom_text_edit.cpp

              #include "custom_text_edit.h"
              
              custom_text_Edit::custom_text_Edit()
              {
              
              }
              
              void custom_text_Edit::mousePressEvent(QMouseEvent *event)
              {
                  qDebug("pressed inside qtextedit \n");
              }
              
              

              custom_text_edit.h

              #ifndef CUSTOM_TEXT_EDIT_H
              #define CUSTOM_TEXT_EDIT_H
              
              #include <QTextEdit>
              
              class custom_text_Edit : public QTextEdit
              {
              public:
                  custom_text_Edit();
              
              protected:
                  void mousePressEvent(QMouseEvent *event) override;
              };
              
              #endif // CUSTOM_TEXT_EDIT_H
              
              

              I create class instance in my main.cpp:

              custom_text_Edit cte;
              

              Is there anything else I am missing? When I click on the QTextEdit widget ( my console), I still cannot trigger the mouseclick event that I just overriden

              JonBJ Online
              JonBJ Online
              JonB
              wrote on last edited by JonB
              #29

              @lukutis222
              Are you 100% sure you have changed your QTextEdit, designed in Qt Designer, over to this new custom_text_Edit? How did you manage that (without promoting)?

              Which is one reason this subclassing instead of eventFilter() is going to be a pain for you.... Event filter allows you to intercept events without having to subclass, which I believe is what you requested/would like.

              1 Reply Last reply
              2
              • L Offline
                L Offline
                lukutis222
                wrote on last edited by
                #30

                @JonB @jsulm

                Ok so that is what promoting is used for! Thank you both very much I have managed to do it by promoting my console to my new custom_text_Edit class and when I click on the console I get the event triggered. I revert my console back to QTextEdit class and will now look into eventfilters

                JonBJ 1 Reply Last reply
                1
                • L lukutis222

                  @JonB @jsulm

                  Ok so that is what promoting is used for! Thank you both very much I have managed to do it by promoting my console to my new custom_text_Edit class and when I click on the console I get the event triggered. I revert my console back to QTextEdit class and will now look into eventfilters

                  JonBJ Online
                  JonBJ Online
                  JonB
                  wrote on last edited by JonB
                  #31

                  @lukutis222
                  Note that Qt has two means of "notifying" that something has happened. Events are just protected methods and require subclassing if you need to know about them . Signals on the other hand are public methods and you can attach slots to be notified of their occurrence without needing to subclass. (Note also that in an event you can alter the behaviour of the handling of the event, if you wish to, but in a signal you cannot, the action has already happened and you can only add your own behaviour not alter the action's existing behaviour.) For example, mouse up/down are events, but "click" is a signal; same for key presses as opposed to, say, the textChanged() signal after a down/up. Nobody knows the official definition/determination of when an action is exposed as a signal rather than an event, but basically the lowest level activities are events and higher level ones are signals.

                  eventFilter() is neither an event nor a signal. It is a method you can install as a "hook" for any low level event which may arise, allowing you either to just monitor it (as in your case) or alter what happens to it before further Qt processing. It conveniently allows any event to any widget to be intercepted without needing to subclass.

                  D 1 Reply Last reply
                  3
                  • JonBJ JonB

                    @lukutis222
                    Note that Qt has two means of "notifying" that something has happened. Events are just protected methods and require subclassing if you need to know about them . Signals on the other hand are public methods and you can attach slots to be notified of their occurrence without needing to subclass. (Note also that in an event you can alter the behaviour of the handling of the event, if you wish to, but in a signal you cannot, the action has already happened and you can only add your own behaviour not alter the action's existing behaviour.) For example, mouse up/down are events, but "click" is a signal; same for key presses as opposed to, say, the textChanged() signal after a down/up. Nobody knows the official definition/determination of when an action is exposed as a signal rather than an event, but basically the lowest level activities are events and higher level ones are signals.

                    eventFilter() is neither an event nor a signal. It is a method you can install as a "hook" for any low level event which may arise, allowing you either to just monitor it (as in your case) or alter what happens to it before further Qt processing. It conveniently allows any event to any widget to be intercepted without needing to subclass.

                    D Offline
                    D Offline
                    dan1973
                    wrote on last edited by
                    #32

                    @JonB Wow!!

                    1 Reply Last reply
                    0
                    • L Offline
                      L Offline
                      lukutis222
                      wrote on last edited by lukutis222
                      #33

                      @JonB Thank you very much for all this useful information. After reading a little about bit about the eventfilters and looking at some examples (https://forum.qt.io/topic/110350/how-to-make-an-eventfilter/2), I have changed my implemented eventfilter in my widget component.

                      In my widget.cpp, I have added:

                      bool Widget::eventFilter(QObject *object, QEvent *event)
                      {
                          //qDebug("event filter \n");
                      
                          if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                              qDebug("mouse clicked \n");
                          }
                          if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                              qDebug("mouse double click \n");
                          }
                      
                      
                      
                          return false;
                      }
                      

                      And in the widget constructor:

                      ui->Console_read->installEventFilter(this); // console read is the QTextEdit window that I would like to detect mouse clicks on
                      

                      in my widget.h
                      I have added function prototype under the private section:

                      private:
                          Ui::Widget *ui;
                          bool eventFilter(QObject *object, QEvent *event);
                      
                      

                      However, it does not seem to work as I expected. I was expecting the below to be triggered when I click anywhere on the console

                          if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                              qDebug("mouse clicked \n");
                          }
                      

                      and below to be triggered when I double click anywhere on the console.

                          if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                              qDebug("mouse double click \n");
                          }
                      

                      However, the event filter does not react to the left mouse button click and double left mouse button click.

                      When I right click mouse button, the event filter triggers MouseButtonPress. Why would it react to right click for MouseButtonPress Is that default? Do I need to override the MouseButtonPress?

                      jsulmJ JonBJ 2 Replies Last reply
                      0
                      • L lukutis222

                        @JonB Thank you very much for all this useful information. After reading a little about bit about the eventfilters and looking at some examples (https://forum.qt.io/topic/110350/how-to-make-an-eventfilter/2), I have changed my implemented eventfilter in my widget component.

                        In my widget.cpp, I have added:

                        bool Widget::eventFilter(QObject *object, QEvent *event)
                        {
                            //qDebug("event filter \n");
                        
                            if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                                qDebug("mouse clicked \n");
                            }
                            if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                                qDebug("mouse double click \n");
                            }
                        
                        
                        
                            return false;
                        }
                        

                        And in the widget constructor:

                        ui->Console_read->installEventFilter(this); // console read is the QTextEdit window that I would like to detect mouse clicks on
                        

                        in my widget.h
                        I have added function prototype under the private section:

                        private:
                            Ui::Widget *ui;
                            bool eventFilter(QObject *object, QEvent *event);
                        
                        

                        However, it does not seem to work as I expected. I was expecting the below to be triggered when I click anywhere on the console

                            if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                                qDebug("mouse clicked \n");
                            }
                        

                        and below to be triggered when I double click anywhere on the console.

                            if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                                qDebug("mouse double click \n");
                            }
                        

                        However, the event filter does not react to the left mouse button click and double left mouse button click.

                        When I right click mouse button, the event filter triggers MouseButtonPress. Why would it react to right click for MouseButtonPress Is that default? Do I need to override the MouseButtonPress?

                        jsulmJ Offline
                        jsulmJ Offline
                        jsulm
                        Lifetime Qt Champion
                        wrote on last edited by
                        #34

                        @lukutis222 Print out what event->type() returns in your eventFilter and see what you get when you press left mouse button. For left mouse button click you should get two events: QEvent::MouseButtonPress and QEvent::MouseButtonRelease.

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

                        L 1 Reply Last reply
                        0
                        • L lukutis222

                          @JonB Thank you very much for all this useful information. After reading a little about bit about the eventfilters and looking at some examples (https://forum.qt.io/topic/110350/how-to-make-an-eventfilter/2), I have changed my implemented eventfilter in my widget component.

                          In my widget.cpp, I have added:

                          bool Widget::eventFilter(QObject *object, QEvent *event)
                          {
                              //qDebug("event filter \n");
                          
                              if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                                  qDebug("mouse clicked \n");
                              }
                              if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                                  qDebug("mouse double click \n");
                              }
                          
                          
                          
                              return false;
                          }
                          

                          And in the widget constructor:

                          ui->Console_read->installEventFilter(this); // console read is the QTextEdit window that I would like to detect mouse clicks on
                          

                          in my widget.h
                          I have added function prototype under the private section:

                          private:
                              Ui::Widget *ui;
                              bool eventFilter(QObject *object, QEvent *event);
                          
                          

                          However, it does not seem to work as I expected. I was expecting the below to be triggered when I click anywhere on the console

                              if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                                  qDebug("mouse clicked \n");
                              }
                          

                          and below to be triggered when I double click anywhere on the console.

                              if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                                  qDebug("mouse double click \n");
                              }
                          

                          However, the event filter does not react to the left mouse button click and double left mouse button click.

                          When I right click mouse button, the event filter triggers MouseButtonPress. Why would it react to right click for MouseButtonPress Is that default? Do I need to override the MouseButtonPress?

                          JonBJ Online
                          JonBJ Online
                          JonB
                          wrote on last edited by JonB
                          #35

                          @lukutis222
                          I don't know why you are not getting the left mouse button, especially as you say you do for the right button. Like @jsulm I would expect a mouse press and a mouse release. Start by removing your object == ui->Console_read &&, let's see whether you get these anywhere regardless of object? Also do as @jsulm says: log every event arriving in your eventFilter(), see if there is anything else there of interest.

                          1 Reply Last reply
                          0
                          • jsulmJ jsulm

                            @lukutis222 Print out what event->type() returns in your eventFilter and see what you get when you press left mouse button. For left mouse button click you should get two events: QEvent::MouseButtonPress and QEvent::MouseButtonRelease.

                            L Offline
                            L Offline
                            lukutis222
                            wrote on last edited by lukutis222
                            #36

                            @jsulm said in How to reposition cursor to the end of the document without autoscroll:

                            Print out what event->type(

                            When I hover my mouse over console, events 10 and 110 are generated

                            When cursor leaves the console area, event 11 is generated

                            When I left click on my console, event = 207 is generated.

                            When I click left mouse button multiple times(double click), multiple 207 events are generated:

                            event->type() = 207 
                            event->type() = 207 
                            event->type() = 207 
                            event->type() = 207 
                            

                            Right mouse button click generates 4 events:

                            event->type() = 2 
                            mouse clicked 
                            event->type() = 9 
                            event->type() = 12 
                            event->type() = 11 
                            
                            bool Widget::eventFilter(QObject *object, QEvent *event)
                            {
                            
                                qDebug("event->type() = %u \n",event->type());
                                if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                                    qDebug("mouse clicked \n");
                                }
                            
                            
                                if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                                    qDebug("mouse double click \n");
                                }
                            
                                return false;
                            }
                            

                            069a7e14-c50b-432f-80a9-abd570774a99-image.png

                            Additionally, I tried to remove object == ui->Console_read but does not have any different affect

                            JonBJ 1 Reply Last reply
                            0
                            • L lukutis222

                              @jsulm said in How to reposition cursor to the end of the document without autoscroll:

                              Print out what event->type(

                              When I hover my mouse over console, events 10 and 110 are generated

                              When cursor leaves the console area, event 11 is generated

                              When I left click on my console, event = 207 is generated.

                              When I click left mouse button multiple times(double click), multiple 207 events are generated:

                              event->type() = 207 
                              event->type() = 207 
                              event->type() = 207 
                              event->type() = 207 
                              

                              Right mouse button click generates 4 events:

                              event->type() = 2 
                              mouse clicked 
                              event->type() = 9 
                              event->type() = 12 
                              event->type() = 11 
                              
                              bool Widget::eventFilter(QObject *object, QEvent *event)
                              {
                              
                                  qDebug("event->type() = %u \n",event->type());
                                  if ((object == ui->Console_read) && (event->type() == QEvent::MouseButtonPress) )   {
                                      qDebug("mouse clicked \n");
                                  }
                              
                              
                                  if ( object == ui->Console_read &&  ( event->type() == QEvent::MouseButtonDblClick )  ) {
                                      qDebug("mouse double click \n");
                                  }
                              
                                  return false;
                              }
                              

                              069a7e14-c50b-432f-80a9-abd570774a99-image.png

                              Additionally, I tried to remove object == ui->Console_read but does not have any different affect

                              JonBJ Online
                              JonBJ Online
                              JonB
                              wrote on last edited by
                              #37

                              @lukutis222
                              If you wait a few minutes I will knock up a tiny sample (I am Linux and Qt5,15, you never seem to have said what you are) with a QTextEdit and see whether I get the left mouse button press/release.... Come back and look in a while :)

                              L 1 Reply Last reply
                              0
                              • JonBJ JonB

                                @lukutis222
                                If you wait a few minutes I will knock up a tiny sample (I am Linux and Qt5,15, you never seem to have said what you are) with a QTextEdit and see whether I get the left mouse button press/release.... Come back and look in a while :)

                                L Offline
                                L Offline
                                lukutis222
                                wrote on last edited by
                                #38

                                @JonB Of course I will be around, I appreciate a lot.

                                I use:
                                ac7a2854-74c9-4721-a586-526fb897d5f6-image.png

                                on my windows 10 machine

                                JonBJ 1 Reply Last reply
                                0
                                • L lukutis222

                                  @JonB Of course I will be around, I appreciate a lot.

                                  I use:
                                  ac7a2854-74c9-4721-a586-526fb897d5f6-image.png

                                  on my windows 10 machine

                                  JonBJ Online
                                  JonBJ Online
                                  JonB
                                  wrote on last edited by JonB
                                  #39

                                  @lukutis222
                                  Please note that tells you your Creator was built with Qt 6.3.1, but not what version of Qt you downloaded and use for you application. Anyway at a guess it's some Qt 6. Whatever, my test will be Linux + Qt 5.15, you will have to see how that behaves for you.

                                  L 1 Reply Last reply
                                  0
                                  • JonBJ JonB

                                    @lukutis222
                                    Please note that tells you your Creator was built with Qt 6.3.1, but not what version of Qt you downloaded and use for you application. Anyway at a guess it's some Qt 6. Whatever, my test will be Linux + Qt 5.15, you will have to see how that behaves for you.

                                    L Offline
                                    L Offline
                                    lukutis222
                                    wrote on last edited by lukutis222
                                    #40

                                    @JonB
                                    Based on my directory folders I assume the project is also 6_3_1:
                                    b94c4bd9-7e15-4fa0-808d-21e275ee806b-image.png

                                    Anyways, in my application, apart from the Console I have a write box where user can write commands to the serial device:

                                    92d37dd9-187d-424d-81bd-7d44d2b877f5-image.png

                                    Just for testing purpose, I have created eventfilter2 for QLineEdit events and I can see that it behaves differently than QTextEdit:
                                    When I left click mouse button on the small rectangular text box at the bottom of my application, many events are generated(Just from one left mouse button click):

                                    event->type() = 213 
                                    event->type() = 71 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 110 
                                    event->type() = 207 
                                    event->type() = 8 
                                    event->type() = 207 
                                    event->type() = 207 
                                    event->type() = 207 
                                    event->type() = 2 
                                    mouse clicked 
                                    event->type() = 207 
                                    event->type() = 207 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 3 
                                    event->type() = 207 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    event->type() = 12 
                                    event->type() = 170 
                                    event->type() = 170 
                                    
                                    

                                    As you can see from above, one of the events were triggered mouse clicked so that seem to work (Im not sure why it is creating so many 12 170 170 events over and over again )

                                    JonBJ 1 Reply Last reply
                                    0
                                    • L lukutis222

                                      @JonB
                                      Based on my directory folders I assume the project is also 6_3_1:
                                      b94c4bd9-7e15-4fa0-808d-21e275ee806b-image.png

                                      Anyways, in my application, apart from the Console I have a write box where user can write commands to the serial device:

                                      92d37dd9-187d-424d-81bd-7d44d2b877f5-image.png

                                      Just for testing purpose, I have created eventfilter2 for QLineEdit events and I can see that it behaves differently than QTextEdit:
                                      When I left click mouse button on the small rectangular text box at the bottom of my application, many events are generated(Just from one left mouse button click):

                                      event->type() = 213 
                                      event->type() = 71 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 110 
                                      event->type() = 207 
                                      event->type() = 8 
                                      event->type() = 207 
                                      event->type() = 207 
                                      event->type() = 207 
                                      event->type() = 2 
                                      mouse clicked 
                                      event->type() = 207 
                                      event->type() = 207 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 3 
                                      event->type() = 207 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      event->type() = 12 
                                      event->type() = 170 
                                      event->type() = 170 
                                      
                                      

                                      As you can see from above, one of the events were triggered mouse clicked so that seem to work (Im not sure why it is creating so many 12 170 170 events over and over again )

                                      JonBJ Online
                                      JonBJ Online
                                      JonB
                                      wrote on last edited by JonB
                                      #41

                                      @lukutis222
                                      OK, it gets complicated. Full story probably in https://stackoverflow.com/questions/41631011/my-qt-eventfilter-doesnt-stop-events-as-it-should. I agree QTextEdit behaves differently from QLineEdit. I said you may need

                                      Look at installing an application event filter

                                      and you do.

                                      Here is my sample application:

                                      #include <QCoreApplication>
                                      #include <QDebug>
                                      #include <QLineEdit>
                                      #include <QTextEdit>
                                      #include <QVBoxLayout>
                                      
                                      #include "widget.h"
                                      
                                      Widget::Widget(QWidget *parent)
                                          : QWidget(parent)
                                      {
                                          QVBoxLayout *vlayout = new QVBoxLayout;
                                          QLineEdit *lineEdit = new QLineEdit;
                                          lineEdit->setObjectName("lineEdit");
                                          vlayout->addWidget(lineEdit);
                                          QTextEdit *textEdit = new QTextEdit;
                                          textEdit->setObjectName("textEdit");
                                          vlayout->addWidget(textEdit);
                                          setLayout(vlayout);
                                      
                                         QCoreApplication::instance()->installEventFilter(this);
                                         lineEdit->installEventFilter(this);
                                         textEdit->installEventFilter(this);
                                      }
                                      
                                      Widget::~Widget()
                                      {
                                      }
                                      
                                      bool Widget::eventFilter(QObject *obj, QEvent *event)
                                      {
                                      //    qDebug() << event->type();
                                          if (event->type() == QEvent::MouseButtonPress || event->type() == QEvent::MouseButtonRelease)
                                              qDebug() << "Mouse button event" << obj->objectName() << event->type();
                                          // pass the event on to the parent class
                                          return QWidget::eventFilter(obj, event);
                                      }
                                      

                                      Note how I use QCoreApplication::instance()->installEventFilter(this);.

                                      Output (from left-clicking in each of the line edit and text edit) is:

                                      11:17:36: Debugging starts
                                      Mouse button event "WidgetClassWindow" QEvent::MouseButtonPress
                                      Mouse button event "lineEdit" QEvent::MouseButtonPress
                                      Mouse button event "lineEdit" QEvent::MouseButtonPress
                                      Mouse button event "WidgetClassWindow" QEvent::MouseButtonRelease
                                      Mouse button event "lineEdit" QEvent::MouseButtonRelease
                                      Mouse button event "lineEdit" QEvent::MouseButtonRelease
                                      Mouse button event "WidgetClassWindow" QEvent::MouseButtonPress
                                      Mouse button event "qt_scrollarea_viewport" QEvent::MouseButtonPress
                                      Mouse button event "WidgetClassWindow" QEvent::MouseButtonRelease
                                      Mouse button event "qt_scrollarea_viewport" QEvent::MouseButtonRelease
                                      11:17:41: Debugging has finished
                                      

                                      See how for the QTextEdit the mouse events actually go to qt_scrollarea_viewport.

                                      I leave you to play with this/adapt to your needs.

                                      L 1 Reply Last reply
                                      1
                                      • D Offline
                                        D Offline
                                        dan1973
                                        wrote on last edited by
                                        #42

                                        @lukutis222
                                        "Yes I figured that but its not fully clear how to do it since I do not have a seperate class for QTextEdit. Can I do that in my Widget component?"

                                        slot function:

                                        QObject* objTE1 = QObject::sender();
                                        if (objTE1 == textEdit) { // you can catch the click or press event here. you should declare textEdit public to access.
                                               <do action on mouse press or click event here>
                                        }
                                        

                                        you can use to catch the click or mouse press event here by connecting the signal (click or press) of the textEdit obj to any defined slot above. this way you can always catch the specific child Widget

                                        1 Reply Last reply
                                        0
                                        • JonBJ JonB

                                          @lukutis222
                                          OK, it gets complicated. Full story probably in https://stackoverflow.com/questions/41631011/my-qt-eventfilter-doesnt-stop-events-as-it-should. I agree QTextEdit behaves differently from QLineEdit. I said you may need

                                          Look at installing an application event filter

                                          and you do.

                                          Here is my sample application:

                                          #include <QCoreApplication>
                                          #include <QDebug>
                                          #include <QLineEdit>
                                          #include <QTextEdit>
                                          #include <QVBoxLayout>
                                          
                                          #include "widget.h"
                                          
                                          Widget::Widget(QWidget *parent)
                                              : QWidget(parent)
                                          {
                                              QVBoxLayout *vlayout = new QVBoxLayout;
                                              QLineEdit *lineEdit = new QLineEdit;
                                              lineEdit->setObjectName("lineEdit");
                                              vlayout->addWidget(lineEdit);
                                              QTextEdit *textEdit = new QTextEdit;
                                              textEdit->setObjectName("textEdit");
                                              vlayout->addWidget(textEdit);
                                              setLayout(vlayout);
                                          
                                             QCoreApplication::instance()->installEventFilter(this);
                                             lineEdit->installEventFilter(this);
                                             textEdit->installEventFilter(this);
                                          }
                                          
                                          Widget::~Widget()
                                          {
                                          }
                                          
                                          bool Widget::eventFilter(QObject *obj, QEvent *event)
                                          {
                                          //    qDebug() << event->type();
                                              if (event->type() == QEvent::MouseButtonPress || event->type() == QEvent::MouseButtonRelease)
                                                  qDebug() << "Mouse button event" << obj->objectName() << event->type();
                                              // pass the event on to the parent class
                                              return QWidget::eventFilter(obj, event);
                                          }
                                          

                                          Note how I use QCoreApplication::instance()->installEventFilter(this);.

                                          Output (from left-clicking in each of the line edit and text edit) is:

                                          11:17:36: Debugging starts
                                          Mouse button event "WidgetClassWindow" QEvent::MouseButtonPress
                                          Mouse button event "lineEdit" QEvent::MouseButtonPress
                                          Mouse button event "lineEdit" QEvent::MouseButtonPress
                                          Mouse button event "WidgetClassWindow" QEvent::MouseButtonRelease
                                          Mouse button event "lineEdit" QEvent::MouseButtonRelease
                                          Mouse button event "lineEdit" QEvent::MouseButtonRelease
                                          Mouse button event "WidgetClassWindow" QEvent::MouseButtonPress
                                          Mouse button event "qt_scrollarea_viewport" QEvent::MouseButtonPress
                                          Mouse button event "WidgetClassWindow" QEvent::MouseButtonRelease
                                          Mouse button event "qt_scrollarea_viewport" QEvent::MouseButtonRelease
                                          11:17:41: Debugging has finished
                                          

                                          See how for the QTextEdit the mouse events actually go to qt_scrollarea_viewport.

                                          I leave you to play with this/adapt to your needs.

                                          L Offline
                                          L Offline
                                          lukutis222
                                          wrote on last edited by
                                          #43

                                          @JonB Thanks a lot. That fixed to issue and now I am able to trigger mouse click events :)

                                          1 Reply Last reply
                                          0

                                          • Login

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved