【Qt笔记】键盘控制Qt按钮

标签：clicked Qt currentButton button 键盘 QString QPushButton 按钮

一、前言

Qt框架支持通过键盘输入来间接控制界面元素，如按钮，实现无需鼠标操作的交互方式。这通常涉及到键盘事件的监听与处理，比如监听特定的按键事件（如空格键、回车键等），并在这些事件发生时模拟鼠标点击行为，触发按钮的点击事件。本文通过重写键盘事件处理函数keyPressEvent来实现这一功能，从而为应用程序添加更丰富的交互体验和便捷性。

二、初始化

创建多个按钮并添加到网格布局中，并将按钮的点击信号与槽函数相连接，以方便后续验证键盘控制效果。

// 创建网格布局
QGridLayout *grid = new QGridLayout(this);

// 创建按钮
QPushButton *button1 = new QPushButton("按钮1");
QPushButton *button2 = new QPushButton("按钮2");
QPushButton *button3 = new QPushButton("按钮3");
QPushButton *button4 = new QPushButton("按钮4");

//链接按钮点击信号与槽函数
connect(button1, &QPushButton::clicked, this, &Widget::Button_clicked);
connect(button2, &QPushButton::clicked, this, &Widget::Button_clicked);
connect(button3, &QPushButton::clicked, this, &Widget::Button_clicked);
connect(button4, &QPushButton::clicked, this, &Widget::Button_clicked);

// 将按钮添加到网格布局
grid->addWidget(button1, 0, 0); // 将button1添加到第0行第0列
grid->addWidget(button2, 0, 1); // 将button2添加到第0行第1列
grid->addWidget(button3, 1, 0); // 将button3添加到第1行第0列
grid->addWidget(button4, 1, 1); // 将button3添加到第1行第1列

设置按钮的objectname，并将按钮保存到QList中去，方便后续键盘控制按钮时知道需要控制哪个按钮。

//设置button的objectname
button1->setObjectName(QString("button-0-0"));
button2->setObjectName(QString("button-0-1"));
button3->setObjectName(QString("button-1-0"));
button4->setObjectName(QString("button-1-1"));

//将按钮添加到QList中去
buttons << button1 << button2 << button3 << button4;

初始化的整体代码：

//键盘控制按钮的选中
void Widget::keyboardChoose()
{
    // 创建网格布局
    QGridLayout *grid = new QGridLayout(this);

    // 创建按钮
    QPushButton *button1 = new QPushButton("按钮1");
    QPushButton *button2 = new QPushButton("按钮2");
    QPushButton *button3 = new QPushButton("按钮3");
    QPushButton *button4 = new QPushButton("按钮4");

    //链接按钮点击信号与槽函数
    connect(button1, &QPushButton::clicked, this, &Widget::Button_clicked);
    connect(button2, &QPushButton::clicked, this, &Widget::Button_clicked);
    connect(button3, &QPushButton::clicked, this, &Widget::Button_clicked);
    connect(button4, &QPushButton::clicked, this, &Widget::Button_clicked);

    //设置button的objectname
    button1->setObjectName(QString("button-0-0"));
    button2->setObjectName(QString("button-0-1"));
    button3->setObjectName(QString("button-1-0"));
    button4->setObjectName(QString("button-1-1"));

    //将按钮添加到QList中去
    buttons << button1 << button2 << button3 << button4;

    // 将按钮添加到网格布局
    grid->addWidget(button1, 0, 0); // 将button1添加到第0行第0列
    grid->addWidget(button2, 0, 1); // 将button2添加到第0行第1列
    grid->addWidget(button3, 1, 0); // 将button3添加到第1行第0列
    grid->addWidget(button4, 1, 1); // 将button3添加到第1行第1列

    //设置按钮边界
    down = 1;
    right = 1;

    // 初始选中第一个按钮
    currentButton = buttons[0];
    currentButton->setStyleSheet("QPushButton:focus { background-color: yellow; }");
}

三、键盘移动后需要选中哪个按钮

通过遍历之前保存button的QList，比较每个button的objectname属性，找到需要选中的那个按钮

QPushButton* Widget::judgeMove(QString newButtonName)
{
    QPushButton *button = nullptr;
    for(auto it : buttons)
    {
        if(it->objectName() == newButtonName)
        {
            button = it;
        }
    }
    return button;
}

四、键盘按键处理函数

本文将W键设置为上，S键设置为下，A键设置为左，D键设置为右，Enter键设置为点击按钮

//键盘按键处理函数
void Widget::keyPressEvent(QKeyEvent *event)
{
    QStringList list = currentButton->objectName().split("-");
    switch (event->key()) {
    case Qt::Key_W:
        //up
        if (list.at(1).toInt() > 0) {
            currentButton->setStyleSheet("");
            QString newButtonName = QString("button-%1-%2").arg(list.at(1).toInt() - 1).arg(list.at(2));
            currentButton = judgeMove(newButtonName);
            if(currentButton)
            {
                currentButton->setStyleSheet("QPushButton:focus { background-color: yellow; }");
                currentButton->setFocus();
            }
        }
        break;
    case Qt::Key_S:
        //down
        if (list.at(1).toInt() < down) {
            currentButton->setStyleSheet("");
            QString newButtonName = QString("button-%1-%2").arg(list.at(1).toInt() + 1).arg(list.at(2));
            currentButton = judgeMove(newButtonName);
            if(currentButton)
            {
                currentButton->setStyleSheet("QPushButton:focus { background-color: yellow; }");
                currentButton->setFocus();
            }
        }
        break;
    case Qt::Key_A:
        //left
        if (list.at(2).toInt() > 0) {
            currentButton->setStyleSheet("");
            QString newButtonName = QString("button-%1-%2").arg(list.at(1)).arg(list.at(2).toInt() - 1);
            currentButton = judgeMove(newButtonName);
            if(currentButton)
            {
                currentButton->setStyleSheet("QPushButton:focus { background-color: yellow; }");
                currentButton->setFocus();
            }
        }
        break;
    case Qt::Key_D:
        //right
        if (list.at(2).toInt() < right) {
            currentButton->setStyleSheet("");
            QString newButtonName = QString("button-%1-%2").arg(list.at(1)).arg(list.at(2).toInt() + 1);
            currentButton = judgeMove(newButtonName);
            if(currentButton)
            {
                currentButton->setStyleSheet("QPushButton:focus { background-color: yellow; }");
                currentButton->setFocus();
            }
        }
        break;
    case 16777220:
        //Enter
        currentButton->click();
        break;
    default:
        QWidget::keyPressEvent(event);
    }
}

五、实现效果

标签：clicked,Qt,currentButton,button,键盘,QString,QPushButton,按钮
From： https://blog.csdn.net/qq_52924376/article/details/141225062