QtWidgets应用程序的虚拟键盘或屏幕键盘？

Question

我将部署这样的屏幕键盘（取自基于QML的Qt虚拟键盘）

我应该如何实现？

针对基于窗口小部件的应用程序是否有任何文档或解决方案？

Answer 1

您只需要在main.cpp中添加此行

qputenv("QT_IM_MODULE", QByteArray("qtvirtualkeyboard"));

，并且可以在Qtwidgets中使用虚拟键盘））

Answer 2

终于找到了解决方案！

您只需要调用QGuiApplication::inputMethod()来获取应用程序范围的Qt输入法，然后调用QInputMethod::keyboardRectangle()和QInputMethod::isVisible()来获取输入法属性，然后保持基于小部件位置的计算和键盘坐标，这是一个可以共享的完整示例：

lineedit.h：

class LineEdit :public QLineEdit {
    Q_OBJECT

public:
    LineEdit(QWidget *parent = nullptr);
    LineEdit(const QString&, QWidget *parent = nullptr);

protected:
    bool event(QEvent*) override;

private:
    bool _moved = false;
    int _lastDiff = 0;
};

lineedit.cpp：

LineEdit::LineEdit(QWidget *parent) :QLineEdit(parent) {
    setAttribute(Qt::WA_InputMethodEnabled, true);
    setInputMethodHints(inputMethodHints() | Qt::InputMethodHint::ImhDigitsOnly);
}

LineEdit::LineEdit(const QString& txt, QWidget *parent) : QLineEdit(txt, parent) {
    setAttribute(Qt::WA_InputMethodEnabled, true);
    setInputMethodHints(inputMethodHints() | Qt::InputMethodHint::ImhDigitsOnly);
}

bool LineEdit::event(QEvent* e) {
    const auto keyboard_rect = QGuiApplication::inputMethod()->keyboardRectangle();
    const auto keyboard_visible = QGuiApplication::inputMethod()->isVisible();
    const auto global_y = QWidget::mapToGlobal(rect().topLeft()).y() + height();
    const auto k_global_y = keyboard_rect.topLeft().y();
    const auto diff = k_global_y - global_y;
    const auto need_to_move = diff < 0;

    /* move main widget */
    if (keyboard_visible && !_moved && need_to_move) {
        _moved = true;
        _lastDiff = diff;
        const auto g = parentWidget()->frameGeometry();
        parentWidget()->move(g.x(), g.y() - qAbs(_lastDiff));
    }
    /* roll back */
    if (!keyboard_visible && _moved) {
        _moved = false;
        const auto g = parentWidget()->frameGeometry();
        parentWidget()->move(g.x(), g.y() + qAbs(_lastDiff));
    }
    return QLineEdit::event(e);
}

main.cpp：

#include <QtWidgets>

#define W 1024
#define H 768

int main(int argc, char *argv[]) {
    qputenv("QT_IM_MODULE", QByteArray("qtvirtualkeyboard"));
    QApplication app(argc, argv);

    QMainWindow window(nullptr, Qt::FramelessWindowHint);

    LineEdit lineedit1(&window);
    lineedit1.move(100, 450);

    LineEdit lineedit2(&window);
    lineedit2.move(100, 100);

    window.resize(W, H);
    window.show();
    return app.exec();
}

结果：