Insert fill circle into cell of QTableWidget



  • @mrjj
    Do you show me how to make??


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    Please read about userRoles and setData

    http://doc.qt.io/qt-5/model-view-programming.html
    section Item roles

    you can simply put the color / size in user role, or you can have
    it directly as an item in your model.
    Both ways are fine.
    Then delegate read the user role and use the data.



  • I read it and I have tried it but my problem is that size circle depends that value of class and colour of background another value of class. I don't know how do it...


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    Well the delegate cannot go read into other external classes.
    So you have to at some point take the values from the classes and
    put into the model.
    How often does those values change in the classes ?



  • @mrjj

    The parameters will change very often. There will be hundreds of instances of the class and the values ​​will change.


  • Lifetime Qt Champion

    The problem is not in the number of instances but rather how you access them.

    How are you currently handling these differed classes ?



  • @mrjj @SGaist Hi!!

    The program will be a simulation of the habitat of fungus and fungivores. I have a world class, which contains a matrix (world), and an array of fungivores. The matrix is composed of cell. The cell class contains an array of fungivores (fungivores that are in that cell) and an int that represents the amount of fungus there is. In the course of the execution the value of fungus and the number of fungivores that there will be in each cell will change. That's what I have to represent in the UI. The amount of fungus will represent it by painting the green cells, with an intensity between 0 and 255, depending on the value, and the amount of fungivors will represent it with a circle, the size of the circle will depend on the value. Once I have this sequential version, I will have to make a parallel version.



  • @juaniyoalm
    So can you keep those fungus-intensity-ints in (a column in) your model? Then your view can access it.


  • Lifetime Qt Champion

    Is the matrix a two dimensional table ?



  • @SGaist
    Yes, in each cell there is fungus (int value) and fungivores (array of fungivores).

    I've tried pass QPair or Qlist to QStandarItemModel but is not posible cast to qvariant


  • Lifetime Qt Champion

    What are you currently using to store that "matrix" ?



  • Vector<Vector<Cell>>



  • Some answer please???


  • Lifetime Qt Champion

    Please show some patience and allow 24 hours to run before bumping your own thread. This is a community forum where people answer on their own time. They might not even live in the same timezone as you.

    As for your current trouble. You can build a QAbstractTableModel that will give access to your matrix. For the specific members of your Cell class, you can use custom roles.



  • @SGaist

    I'm sorry, it was my vacation day and I wanted to move forward with the project. I'm sorry.

    To assign the matrix to the model simply the model creates a variable of the same type as the matrix and initialize the model I assign it in some way, is it correct? I do not understand the roles very well ...


  • Lifetime Qt Champion

    You should also provide APIs that will allow you ton modify that matrix.

    As for the roles, they are there to retrieve specific information from the model's elements.



  • @SGaist said in Insert fill circle into cell of QTableWidget:

    You should also provide APIs that will allow you ton modify that matrix.
    As for the roles, they are there to retrieve specific information from the model's elements.

    I'm sorry but I still do not understand well the models and roles in QT.
    Can anyone give me an example of how the model class should be?

    I have a matrix (vector <vector <Cell >>) and when modifying some attributes of the Cell class, have to change what is painted in the graphic representation (Only the one in the cell corresponding to the coordinates of the matrix).


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    Its something like this
    https://meetingcpp.com/blog/items/an-introduction-into-qt-part-3.html
    However he uses a
    std::vector<PersonalData> mydata;
    where you have
    vector <vector <Cell >>
    so you need to use both index.row and index.col
    to address your matrix. ( the data)



  • @mrjj Thanks so much.

    I was doing it that way, but how did I assign the matrix to the model variable? At this moment, I am creating the matrix in mainwindow class ...


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    well the vector <vector <Cell >> matrix could be inside the model
    and you would use method like the Addperson in sample to fill it.
    Much like you do now. when maxtrix is outside of the model.
    You could also fill it in mainwindow and simply give whole matrix to model
    to copy it to internal variable.(matrix) but thats a bit waste full.

    Also i been wanting to ask you. You do use a TableView because you need scrolling correct?
    I mean there are far more rows with cells than can fit on on screen ?



  • @mrjj

    Yes, there is no row limit, it can be 20 rows, 100 or 1000 xD. I always have to think about what I do to behave well when I do the parallel implementation, using pthread and openmp.


  • Lifetime Qt Champion

    @juaniyoalm
    Ok so scrolling is needed:)
    Also make sure to check out QtConcurrent and QThread before jumping to pthread.



  • @mrjj

    ok, I will look it.

    I have a doubt, when I modify a value of the Cell class (this is done in a method of the Cell class ), it will be modified automatically in the model or I have to do model-> setData (model-> index (i, j) , matrix [i] [j] -> getModifiedValue ())? The Cell of matrix are pointer...


  • Lifetime Qt Champion

    @juaniyoalm
    Well if you go with QAbstractTableModel
    your matrix IS the data so if you modify it
    and call dataChanged (model call ) to let view know data has been altered.



  • @mrjj

    ok, this is my model implementation:

    /#include "cellmodel.h"
    
    CellModel::CellModel(QObject *parent) : QAbstractTableModel(parent){}
    CellModel::CellModel(int rows, int columns, int fungivores)
    {
        this->mundo = new World(rows, columns, fungivores);
    }
    
    int CellModel::rowCount(const QModelIndex &parent) const
    {
        return this->mundo->world.size();
    }
    int CellModel::columnCount(const QModelIndex &parent) const
    {
        return this->mundo->world[0].size();
    }
    
    QVariant CellModel::data(const QModelIndex &index, int role) const
    {
        if(!index.isValid())
            return QVariant();
    
        if(index.row() >= mundo->world.size() || index.row() < 0 ||
               index.column() >= mundo->world[0].size() || index.column() < 0)
            return QVariant();
    
        if(role == Qt::DisplayRole || role == Qt::EditRole)
        {
            return this->mundo->world[index.row()][index.column()]->getFood();
        }
        return QVariant();
    }
    
    bool CellModel::setData(const QModelIndex &index, const QVariant &value, int role)
    {
        if (index.isValid() && role == Qt::EditRole && !(index.row() >= this->mundo->world.size() || index.row() < 0 ||
                                                         index.column() >= this->mundo->world[0].size() || index.column() < 0))
        {
            int row = index.row();
            int col = index.column();
    
            this->mundo->world[row][col]->setFood(value.toInt());
    
            emit dataChanged(index, index);
            return true;
        }
        return false;
    }
    
    Qt::ItemFlags CellModel::flags(const QModelIndex &index) const
    {
        if (!index.isValid())
            return Qt::ItemIsEnabled;
        return QAbstractTableModel::flags(index) | Qt::ItemIsEditable;
    }
    
    
    

    if I modify the value in this way: model-> world-> world [0] [0] -> setFood (200);

    1- All row is changed instead of just the selected cell.

    2 - Repaint all matrix, although the data of the others have not changed.


  • Lifetime Qt Champion

    hi
    If you place break point and check
    CellModel::data
    return this->mundo->world[index.row()][index.column()]->getFood();
    is row and index what you expect and does getFood() return different values?

    it looks ok.
    very much like
    http://doc.qt.io/qt-5/qtwidgets-itemviews-addressbook-tablemodel-cpp.html



  • @mrjj Hi!!

    In the variable index I get the whole world object (contains the matrix). Attached image:

    0_1543964832588_Selección_001.png

    I think the problem is in the setData method because if I delete the content of this method (I only leave the return false) the behavior does not change, that is, it continues to paint all row instead of just the one that has been modified.

    EDIT:

    When I modify the value with the setValue method of the Cell class, it does not pass through the setData method.


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    is index.row / col always 0,0 ?
    you can use QDebug to easy see it
    while running.



  • @mrjj

    No, is 0,0 because I have done it this way to test.


  • Lifetime Qt Champion

    @juaniyoalm
    ok, so it returns same data from any index() / cell ?



  • @mrjj

    No, each cell returns a different value, but in the modification of the UI it modifies all row with the value sent.

    EDIT:

    Is it normal that every time I touch the main window, the debug enters the data method of the model?


  • Lifetime Qt Champion

    @juaniyoalm
    Ok. Im not sure whats up.
    Maybe something with indexes().
    Cannot guess it.

    • the debug enters the data method of the model?
      Im not sure what it means ?


  • @mrjj

    I'm sorry, I wanted to say that, in the execution, when I touch the ui, the execution goes through the Data method and reviews all the indexes.

    Was there any way to send you to the app? It's a small app and I need to be able to move forward but I can not find the problem ......


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    You can link to dropbox or google drive. just zip project folder.



  • @mrjj

    This is the project:
    Project

    A short summary:

    At this time only the most basic is implemented.

    Cell Class: Contains an array of fungivores and an integer that represents the fungus. When the number of fungivores increases, the circle of the UI should become larger. When the amount of fungus increases or decreases, the color of the cell of the UI should change.

    Fungivore Class: At this moment it is only created so that it can be instantiated.

    World Class: Contains an array of fungivores (all fungivores of the app that will then be shared between the cells). In addition, it contains a Vector <Vector <Cell >> (Matrix).


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    some function was missing in NewDialog but i just made them return a valid value.
    You model actually seems fine (\o/)
    but i found out you would fill the whole
    row with same Cell , it seems.
    Doing this instead
    alt text

    and little change to Cell ( to to be able to see difference)

    Cell::Cell(QObject *parent) : QObject(parent)
    {
        this->fungus = 10 + (rand() % 5);
    }
    
    

    It now seems to edit fine :)



  • @mrjj Thank you so much!!

    But if you modify a cell with the setfood method, does it modify it well?


  • Lifetime Qt Champion

    @juaniyoalm
    Hi
    You mean via

    void MainWindow::changeVal()
    {
        model->mundo->world[0][0]->setFood(200);
    }
    
    

    Yes it does, but you first see it if u click in cell as you secretly change it directly in list
    and the model dont know.

    so do like this
    model->setData(model->index(2,2),200,Qt::EditRole);
    and it refesh it self.

    alt text



  • @mrjj

    Thanks so much!!

    The problem was in World constructor , as you said.

    once solved this problem, as you will have noticed, I only change the color of the cell, and I also need to change the size of the circle, according to the number of fungivores that there are. How can I pass this data to the model, or to differentiate what data is happening to it?

    EDIT:

    Another problem is that if I modify the values in a loop, for example:

        int count = 0;
        while (count < 3000) {
            for(int i = 0; i < this->rows; i++) {
                for(int j = 0; j < this->col; j++) {
                    model->mundo->world[i][j]->setFood(rand() % 255);
                    //model->setData(model->index(i,j),200,Qt::EditRole);
                    qDebug("El ModelIndex[%i][%i] lleva los datos: %i", i, j, model->mundo->world[i][j]->getFood());
                }
            }
    
            count++;
        }
    

    The UI is not updated until the loop completes. It may be that the loop strangles the events ... that's a big problem for me.


  • Lifetime Qt Champion

    @juaniyoalm said in Insert fill circle into cell of QTableWidget:

    How can I pass this data to the model, or to differentiate what data is happening to it?

    But the model has already access to the Cell structure. ( via model)
    So delegate can read the information and calculate the size of circle with more.

    Regarding the loop.
    Yes, i think the loop will strangle the event loop as 3000 x row x col might take some time.
    One option is to use QCoreApplication::processEvents in the loop but thats not so pretty.
    It would be better to use a timer to change the food over time and keep the UI responsive.


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