Qt状态机QStateMachine

QStateMachine

QState 提供了一种强大且灵活的方式来表示状态机中的状态，通过与状态机类(QStateMachine)和转换类(QSignalTransition， QEventTransition)结合，可以实现复杂的状态逻辑和用户交互。合理使用嵌套状态机、信号转换、动作与动画、历史状态和定时器事件等功能，可以增强应用的交互性和视觉效果。在实际应用中，通过优化状态逻辑和转换规则，可以实现丰富和动态的状态管理功能。注意设置转换条件、信信号槽连接和事件处理逻辑，确保状态转换的正确性和高效性。结合其他 Qt 类和方法，可以实现更多高级功能和应用场景，提高应用的灵活性和可维护性。

官方文档参考：https://doc.qt.io/archives/qt-6.6/qtstatemachine-cpp-guide.html

Qt Class Hierarchy 类继承关系图 https://doc.qt.io/qt-6/hierarchy.html

案例 Demo：上下班打卡

上下班打卡

#include <QStateMachine>
qmake: QT += statemachine
CMake: find_package(Qt6 REQUIRED COMPONENTS StateMachine)
target_link_libraries(mytarget PRIVATE Qt6::StateMachine)

// mainwindow.h
#include <QMainWindow>QT_BEGIN_NAMESPACE
namespace Ui{class MainWindow;}
QT_END_NAMESPACEclass QStateMachine;
class MainWindow : public QMainWindow {Q_OBJECT
public:MainWindow(QWidget *parent = nullptr);~MainWindow();
signals:void isWorkDay(bool);void inOfficeArea(bool);void shouldRemind(bool);void remindFinished();
private:void init();
private slots:void checkConditions();
private:Ui::MainWindow *ui;QStateMachine *machine;QTimer *checkTimer;
};#endif // MAINWINDOW_H

// mainwindow.cpp
#include <QStateMachine>      // QT += statemachine or Qt6::StateMachine
#include <QTimer>
MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow), machine(new QStateMachine(this))
{ui->setupUi(this);init();
}
void MainWindow::init()
{ // 1.创建状态: 空闲->工作日->在办公区域->提醒//若对状态进行分组:创建状态时指定正确的父状态QState *idleState = new QState(machine);QState *workdayState = new QState(machine);QState *locationState = new QState(machine);QState *remindState = new QState(machine);machine->setInitialState(idleState);//2. 设置状态转换idleState->addTransition(this, &MainWindow::isWorkDay, workdayState);workdayState->addTransition(this, &MainWindow::inOfficeArea, locationState);locationState->addTransition(this, &MainWindow::shouldRemind, remindState);remindState->addTransition(this, &MainWindow::remindFinished, idleState);// 比如remindState状态进入时的操作connect(remindState, &QState::entered, this,[=](){ui->label->setText("打卡提醒, 请及时打卡！");ui->pushButton->setEnabled(true);emit remindFinished();});machine->start();// 设置定时检查--纯模拟checkTimer = new QTimer(this);connect(checkTimer, &QTimer::timeout, this, &MainWindow::checkConditions);checkTimer->start(3000);//打卡按钮connect(ui->pushButton,&QPushButton::clicked,this,[=](){auto t=ui->timeEdit->time();QString text;if(t >= QTime(6,45) && t <= QTime(9,30)) text = "上班";else if(t > QTime(9,30) && t < QTime(12,0)) text = "上班迟到";else if(t > QTime(13,30) &&  t < QTime(18,0) )text = "提前下班";else if(t >= QTime(18,0)) text = "下班";ui->label->setText(t.toString() + text + " 打卡成功");});
}void MainWindow::checkConditions()
{QTime t = ui->timeEdit->time();ui->pushButton->setEnabled(false);// 1.判断工作日 QDate::currentDate().dayOfWeek() <= 5; // 周一到周五bool workday = ui->ckBankHoliday->isChecked() ? false :ui->ckWorkDay->isChecked() ? true : false;emit isWorkDay(workday);if(!workday){ui->label->setText(t.toString() + " 假期，无需打卡");return;}// 2.判断位置 (实际用QGeoPositionInfoSource)bool inOffice = ui->ckInOfficeArea->isChecked(); // 在办公区域emit inOfficeArea(inOffice);if(!inOffice){ui->label->setText(t.toString() + " 不在办公区域，无法打卡");return;}//3.上班前/下班后提醒打卡bool isWorkTime = (t >= QTime(6,45) && t <= QTime(23,59));if(!isWorkTime){ui->label->setText(t.toString() + " 无法打卡\n打卡时间 6:45-9:30  18:00-22:30");return;}emit shouldRemind(isWorkTime);
}