Dynamically creating a vector of push buttons to a grid layout in Qt C++

talonxv

Complete beginner at Qt, so bear with me.
I am attempting to create a grid of push buttons similar to a tic tac toe board, but the size will be variable. I've used some tactics found here and on the web but am at a loss at creating it dynamically. I am not having issues outside of creating something dynamically. I'd appreciate any tips or suggestions.

Code was derived from https://github.com/aosama16/Qt-Tic-Tac-Toe in an attempt of understanding.

struct Cell 
{
    QPushButton *cellBtn = nullptr;
    int row = defaults::INVALID_CELL;
    int col = defaults::INVALID_CELL;
    Cell(QPushButton *cellBtn, int row, int col)
        : cellBtn(cellBtn), row(row), col(col) {}
};

void SOSGame::on_StartButton_clicked()
{
    int size = ui->BoardSizeSlider->value();
    buildCellButtons(size);
    /*QMessageBox msg;
    msg.setText();*/
}

std::vector<Cell> SOSGame::buildCellButtons(int boardSize) 
{
    std::vector<Cell> cells;
    cells.reserve(boardSize * boardSize);
    for (size_t row = 0; row < boardSize; ++row) {
        for (size_t col = 0; col < boardSize; ++col) {
            // Add buttons to gridLayout
            QPushButton *btn = new QPushButton();
            btn->setProperty("cell", true);
            ui->GameBoard->addWidget(btn,
                                     static_cast<int>(row),
                                     static_cast<int>(col),
                                     defaults::GUI_CELL_ROW_SPAN,
                                     defaults::GUI_CELL_COLUMN_SPAN);
            // Reference to cells
            cells.emplace_back(btn, row, col);
        }
    }
    // Adjusts window size to fit children widgets added dynamically
    adjustSize();

    // Return by value to allow for RVO (Copy Ellision)
    return cells;
}

Donald Duck

What's ui and adjustSize()?

SGaist

Hi and welcome to devnet,

If you want a two dimensional board, then you need a two dimensional container. For example a vector of vector. That way you have the dynamic in both dimensions.

SamiV123

@SGaist said in Dynamically creating a vector of push buttons to a grid layout in Qt C++:

Hi and welcome to devnet,

If you want a two dimensional board, then you need a two dimensional container. For example a vector of vector. That way you have the dynamic in both dimensions.

Or just a vector with rows*cols items. Then your row, col access becomes vector[row * cols + col]

Single contiguous memory chunk vs. multiple.

JonB

@SamiV123 And not so nice if rows are allowed to be inserted/removed dynamically :)

talonxv

@Donald-Duck

Hi, thanks for your reply. ui->GameBoard was the QGridLayout created in Qt designer.
It turns out that adjustsize() did absolutely nothing. lol.

I was able to get it working, however now I'm in the process of getting connections on click.

talonxv

@SGaist
Hi and thank you!

I originally started with a vector of vectors, and thought that it might have been the problem. I may go back to that thought, thank you. I was able to get it working, but now working on how to add connections/edit text on these buttons after the fact. I appreciate the advice. I'm thinking of trying to use a QTableWidget instead.

SGaist

You can simply iterate your vector and then do the connections you want on the current object in the iteration loop.