Qt绘制五子棋界面

Qt绘制五子棋界面

完成了五子棋的界面的绘制，写个博客总结一下收获。
其实也就四步。

1. 设置窗口大小
2. 画棋盘
3. 画棋子
4. 根据鼠标指向画出准心

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最后得到的效果图如下：

除了第四步里，获取鼠标位置有个坑，其他都没什么难度。
这个坑也就是获取鼠标位置时，发现mouseMoveEvent并没有响应

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原来MouseMoveEvent为了不太耗资源在默认状态下是要鼠标按下才能捕捉到。要想鼠标不按下时的移动也能捕捉到，需要setMouseTracking(true);

QWidget中直接setMouseTracking(true);即可。
但若是在QMainWindow，需再多加一句
ui->centralWidget->setMouseTracking(true);

    setMouseTracking(true);
    ui->centralWidget->setMouseTracking(true);

其他的代码里注释都解释清楚了，就不多说了。

---

MainWindow::MainWindow(QWidget *parent)
        : QMainWindow(parent),
        ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    setFixedSize(750,750);//设置窗口大小
    setWindowTitle("五子棋");
}

---

void MainWindow::paintEvent(QPaintEvent* event)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, true); //抗锯齿
    
    //画背景色
    QPalette palette ;
    palette.setColor(QPalette::Background,QColor("#B1723C"));
    this->setAutoFillBackground(true);
    this->setPalette(palette);
    
    //画棋盘线条
    painter.setPen(QPen(Qt::Black,1,Qt::SolidLine));
    for (int i = 0; i < BoardLength; i++)
    {
        painter.drawLine(BoardMargin+BoardOneSize*i, BoardMargin, BoardMargin+BoardOneSize*i, BoardMargin+(BoardLength-1)*BoardOneSize);
        painter.drawLine(BoardMargin, BoardMargin+BoardOneSize*i, BoardMargin+(BoardLength-1)*BoardOneSize, BoardMargin+BoardOneSize*i);
    }
   	//画棋盘里的五个小黑点
    painter.setBrush(QBrush(Qt::black,Qt::SolidPattern));
    painter.drawRect(BoardMargin+3*BoardOneSize-5,BoardMargin+3*BoardOneSize-5,10,10);
    painter.drawRect(BoardMargin+11*BoardOneSize-5,BoardMargin+3*BoardOneSize-5,10,10);
    painter.drawRect(BoardMargin+11*BoardOneSize-5,BoardMargin+11*BoardOneSize-5,10,10);
    painter.drawRect(BoardMargin+3*BoardOneSize-5,BoardMargin+11*BoardOneSize-5,10,10);
    painter.drawRect(BoardMargin+7*BoardOneSize-5,BoardMargin+7*BoardOneSize-5,10,10);

    
    //画棋子
    QBrush brush;  //设置画刷
    painter.setPen(Qt::NoPen);  //去掉pen，避免画出的棋子边缘带线条
    for (int i = 0; i < BoardLength; i++) {
        for (int j = 0; j < BoardLength; j++) {
            if (Board[i][j] != 0) {
                if (Board[i][j] == Black)
                    brush.setColor(Qt::black);
                else if (Board[i][j] == White)
                    brush.setColor(Qt::white);
                brush.setStyle(Qt::SolidPattern);
                painter.setBrush(brush);
                //x,y坐标都减去15是为了让棋子中心落在交点处
                painter.drawEllipse(i*BoardOneSize + BoardMargin - 15, j * BoardOneSize + BoardMargin - 15, 30, 30);
            }
        }
    }
    
    
	
	//根据鼠标移动画出红色小方框
	//presentRowx是鼠标当前所指向的行，presentcoly是鼠标当前指向的列
	//if判断鼠标是否在棋盘内
	if (presentRowx>=0&&presentcoly>=0&&presentRowx<=BoardLength&&presentcoly<=BoardLength)
    {
        painter.setPen(QPen(Qt::red,2,Qt::SolidLine));
        //根据行号列号计算出落子位置
        int centerx = BoardMargin+presentRowx*BoardOneSize;
        int centery = BoardMargin+presentcoly*BoardOneSize;
        painter.drawLine(centerx-20,centery-20,centerx-10,centery-20);
        painter.drawLine(centerx+10,centery-20,centerx+20,centery-20);
        painter.drawLine(centerx-20,centery-20,centerx-20,centery-10);
        painter.drawLine(centerx-20,centery+10,centerx-20,centery+20);
        painter.drawLine(centerx-20,centery+20,centerx-10,centery+20);
        painter.drawLine(centerx+20,centery+20,centerx+10,centery+20);
        painter.drawLine(centerx+20,centery+20,centerx+20,centery+10);
        painter.drawLine(centerx+20,centery-10,centerx+20,centery-20);
    }
}