Resize window when replacing widget

[Smeeth]

I created a Minesweeper application that allows the user to start a game with different numbers of rows, columns, and bombs.

The first game looks great, and the window fits around game board properly.

However, when I make the board smaller, the columns get spaced out to fill the space of the window and the rows push to the bottom of the screen.

How can I make the window resize to the size it should be so the board is not stretched out? Is there anyway to fit to layout without setting the explicit pixel size of the window?

Here is my window code, and the method where the panel is replaced.

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent),
      clicksCountLbl(new QLabel),
      layout(new QGridLayout)
{
    QAction *gamesAction = menuBar()->addAction("Game");
    connect(gamesAction, &QAction::triggered, this, &MainWindow::openGame);

    QWidget *centralWidget = new QWidget;

    int rows = 10;
    int cols = 10;
    numBombs = 8;
    uncoveredSquares = rows*cols - numBombs;

    panel = new MinesweeperPanel(10, 10, 8, this);
    connect(panel, &MinesweeperPanel::bombClicked, this, [=](void){endGame(false);});
    connect(panel, &MinesweeperPanel::click, this, &MainWindow::click);
    connect(panel, &MinesweeperPanel::uncovered, this, &MainWindow::uncovered);

    layout->addWidget(clicksCountLbl, 0, 1);
    layout->addWidget(panel, 1, 0, 1, 2);

    centralWidget->setLayout(layout);

    this->setCentralWidget(centralWidget);
}

void MainWindow::openGame(){
    GameDialog dialog;

    dialog.exec();

    layout->removeWidget(panel);

    delete panel;

    panel = new MinesweeperPanel(dialog.height(), dialog.width(), dialog.mines());

    layout->addWidget(panel, 1, 0, 1, 2);
    
    this->update();
}

[SGaist]

Hi,

You should also show the implementation of your MinesweeperPanel class.

From the looks of it, you should make its size fixed based on its content.

[Smeeth]

Panel class is rather long. I'll post it below.

I figured there may not be a way to fit to contents. I guess I will just have to do a bit of math to figure it out.

#include "minesweeperpanel.h"
#include <QGridLayout>
#include <QRandomGenerator>
#include <QDebug>
#include <QMessageBox>
#include <QApplication>

int MinesweeperPanel::boxDimensions = 30;

MinesweeperPanel::MinesweeperPanel(int rows, int cols, int numBombs, QWidget *parent) :
    QWidget(parent),
    rows(rows),
    cols(cols),
    numBombs(numBombs)
{

    setStyleSheet("QPushButton{min-width:" + QString::number(boxDimensions) + "px; \
                                max-width:" + QString::number(boxDimensions) + "px; \
                                min-height:" + QString::number(boxDimensions) + "px; \
                                max-height:" + QString::number(boxDimensions) + "px; \
                                background-color:rgb(185,185,185);}");
    QGridLayout *layout = new QGridLayout;
    layout->setSpacing(0);

    //allocate dynamic arrays of size rows
    board = new MinesweeperButton**[cols];
    bombs = new bool*[cols];
    flags = new bool*[cols];
    revealed = new bool*[cols];

    //set up board and initailize bombs
    for (int i = 0; i < rows; i++) {
        //allocate row
        board[i] = new MinesweeperButton*[cols];
        bombs[i] = new bool[cols];
        flags[i] = new bool[cols];
        revealed[i] = new bool[cols];
        for (int j = 0; j < cols; j++){
            //create button
            board[i][j] = new MinesweeperButton;
            board[i][j]->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
            board[i][j]->setIcon(QIcon("://images/facingDown.png"));
            board[i][j]->setIconSize(QSize(boxDimensions, boxDimensions));
            connect(board[i][j], &QPushButton::clicked, this, [=](void){buttonClicked(i,j);});
            connect(board[i][j], &MinesweeperButton::rightClicked, this, [=](void){buttonRightClicked(i,j);});
            layout->addWidget(board[i][j], i, j);
            //initialize all bomb spots to false
            bombs[i][j] = false;
            flags[i][j] = false;
            revealed[i][j] = false;
        }
        // each i-th pointer is now pointing to dynamic array (size rows) of actual int values
    }

    for (int i=0; i<numBombs; i++){
        int x = static_cast<int>(QRandomGenerator::global()->generateDouble() * (rows-1));
        int y = static_cast<int>(QRandomGenerator::global()->generateDouble() * (cols-1));
        bombs[x][y] = true;
    }

    this->setLayout(layout);
}

MinesweeperPanel::~MinesweeperPanel()
{
    for (int i=0; i<rows; i++){
        for (int j=0;j<cols; j++){
            delete board[i][j];
        }
    }
    delete this->layout();
}

/**
 * @brief MinesweeperPanel::buttonClicked
 * Checks for bomb, then starts flood fill from given coordinate
 * @param row
 * @param col
 */
void MinesweeperPanel::buttonClicked(int row, int col){

    if(revealed[row][col])
        return;

    emit click(row, col);

    if (bombs[row][col]){ //bomb clicked
        board[row][col]->setStyleSheet("background-color:red;");
        board[row][col]->setIcon(QIcon("://images/bomb.png"));
        emit bombClicked();
    }

    floodFill(row, col);
}

/**
 * @brief MinesweeperPanel::buttonRightClicked
 * Toggles flag on given coordinates
 * @param row
 * @param col
 */
void MinesweeperPanel::buttonRightClicked(int row, int col){

    if(revealed[row][col])
        return;

    flags[row][col] = !flags[row][col]; //flip flag

    emit flagged(row, col, flags[row][col]);

    if (flags[row][col]){
        board[row][col]->setIcon(QIcon("://images/flagged.png"));
    } else{
        board[row][col]->setIcon(QIcon("://images/facingDown.png"));
    }

}

/**
 * @brief MinesweeperPanel::isWithinBounds
 * @param x
 * @param y
 * @return square is within bounds of grid
 */
bool MinesweeperPanel::isWithinBounds(int x, int y){
    return x>=0 && x<rows && y>=0 && y<cols;
}

/**
 * @brief MinesweeperPanel::floodFill
 * Recursive method that reveals board starting from given coordinates,
 * then checks all neighbors if square has no neighboring bombs.
 * @param x
 * @param y
 */
void MinesweeperPanel::floodFill(int x, int y){

     if (!isWithinBounds(x,y) //if out of bounds
            || bombs[x][y] //or found bomb
            || revealed[x][y]) //or already visited this square
        return;

    revealed[x][y] = true;

    int neighbors = neighboringBombs(x, y);
    board[x][y]->setIcon(QIcon("://images/" + QString::number(neighbors) + ".png"));

    emit uncovered(x,y);

    if (neighbors == 0){
        //search neighbors
        floodFill(x-1, y); //left
        floodFill(x+1, y); //right
        floodFill(x-1, y-1); //left up
        floodFill(x-1, y+1); //left down
        floodFill(x+1, y-1); //right up
        floodFill(x+1, y+1); //right down
        floodFill(x, y+1); //up
        floodFill(x, y-1); //down
    }
}

/**
 * @brief MinesweeperPanel::isBomb
 * @param x
 * @param y
 * @return square contains bomb
 */
bool MinesweeperPanel::isBomb(int x, int y){
    return !isWithinBounds(x,y) //within bounds
            && bombs[x][y]; //is bomb
}

/**
 * @brief MinesweeperPanel::neighboringBombs
 * @param x
 * @param y
 * @return number of neighboring squares that are bombs
 */
int MinesweeperPanel::neighboringBombs(int x, int y){
    int bombNeighbors=0;
    for (int i=-1; i<=1; i++){
        for (int j=-1; j<=1; j++){
            if (isWithinBounds(x+i, y+j) && //is within bounds
                    !(i==0 && j==0) && //don't check current square
                    bombs[x+i][y+j]) //is bomb
              bombNeighbors++;
        }
    }

    return bombNeighbors;
}

/**
 * @brief MinesweeperPanel::revealBoard
 * Uncover all squares in the board
 */
void MinesweeperPanel::revealBoard(){
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++){
            if (!revealed[i][j]){
                if (bombs[i][j])
                    board[i][j]->setIcon(QIcon("://images/bomb.png")); //reveal bomb
                else
                    board[i][j]->setIcon(QIcon("://images/" + QString::number(neighboringBombs(i, j)) + ".png")); //reveal # neighbors
            }
        }
    }
}

[VRonin]

OMG that's a grid of buttons?! that should be implemented with QTableView/QTableWidget

[JonB]

@VRonin
... I can hear the hooves of QStyledItemDelegate thundering toward us... ;)

[JonB]

@Smeeth
If there isn't an automatic size policy you can apply to the main window to shrink to contents (I don't know), what about mainWindow->adjustSize() (or resize(minimumSizeHint()))? You may have to call it on a QTimer after the board's dimensions have been changed.