Qt 状态机编程，双层状态机，实现暂停恢复

流程设计状态图

cpp 复制代码

#ifndef WORKMACHINE_H
#define WORKMACHINE_H

#include <QObject>
#include <QStateMachine>
#include <QHistoryState>
#include <QFinalState>

#include "WorkThread.h"

class WorkMachine : public QObject
{
    Q_OBJECT
public:
    explicit WorkMachine(QObject *parent = nullptr);
    ~WorkMachine();

    void startMachine();
    void runMachineWorkFlow();
    void pauseMachine();
    void resumeMachine();

signals:
    void sigMachineLog(QString log);
    void sigNextState();
    void sigPauseMachine();
    void sigResumeMachine();
    void sigMachineState(int state);

private:
    void initMachine();
    void initStateTrans();
    void initWork();

private:
    // 待机-》 (开门-》关门-》清洗-》甩干-》)  结束
    QStateMachine   m_machine;
    QState          *m_idleState;
    QState          *m_stateOpen;
    QState          *m_stateClose;
    QState          *m_groupStateWork;
    QState          *m_stateWash;
    QState          *m_stateDry;
    QState          *m_statePause;
    QHistoryState   *m_stateHistoryWork;
    bool            m_isPause;
    WorkThread      *m_workThread;
};

#endif // WORKMACHINE_H

cpp 复制代码

#include "WorkMachine.h"
#include <QDebug>

WorkMachine::WorkMachine(QObject *parent)
    : QObject{parent}
{
    initMachine();
    initStateTrans();
    initWork();
    m_isPause = false;
}

WorkMachine::~WorkMachine()
{
    m_groupStateWork->deleteLater();
}

void WorkMachine::startMachine()
{
    if (m_machine.isRunning()) {
        qDebug() << " ********* stop **********";
        m_machine.stop();
        emit sigMachineState(0);
    }
    else {
        qDebug() << "******** machine start work ********";
        m_machine.start();
        emit sigMachineState(1);
        //emit sigMachineLog("******** machine start work ********")
    }
}

void WorkMachine::runMachineWorkFlow()
{
    emit sigNextState();
}

void WorkMachine::pauseMachine()
{
    emit sigPauseMachine();

    m_isPause = true;
}

void WorkMachine::resumeMachine()
{
    emit sigResumeMachine();
    m_isPause = false;
}

void WorkMachine::initMachine()
{
    m_workThread = new WorkThread();

    m_idleState = new QState(&m_machine);
    m_idleState->setObjectName("initialState");
    m_statePause = new QState(&m_machine);
    m_statePause->setObjectName("pauseState");

    m_groupStateWork = new QState(&m_machine);
    m_groupStateWork->setObjectName("stateWork");

    m_stateOpen = new QState(m_groupStateWork);
    m_stateOpen->setObjectName("openState");

    QState *open1 = new QState(m_stateOpen);
    open1->setObjectName("open1State");
    QState *open2 = new QState(m_stateOpen);
    QFinalState *openFinal  = new QFinalState(m_stateOpen);

    open2->setObjectName("open2State");
    m_stateOpen->setInitialState(open1);
    open1->addTransition(this, &WorkMachine::sigNextState, open2);
    open2->addTransition(this, &WorkMachine::sigNextState, openFinal);
    connect(open1, &QState::entered, this, [this](){
        m_workThread->startTask("step 1 open1", 500);
    });
    connect(open2, &QState::entered, this, [this](){
        m_workThread->startTask("step 1 open2", 500);
    });

    m_stateClose = new QState(m_groupStateWork);
    m_stateClose->setObjectName("closeState");

    m_stateWash = new QState(m_groupStateWork);
    m_stateWash->setObjectName("stateWash");

    m_stateDry = new QState(m_groupStateWork);
    m_stateDry->setObjectName("stateDry");

    m_stateHistoryWork = new QHistoryState(m_groupStateWork);
    m_stateHistoryWork->setObjectName("historyState");
    m_stateHistoryWork->setDefaultState(m_stateWash);
    m_stateHistoryWork->setHistoryType(QHistoryState::DeepHistory);

    m_groupStateWork->setChildMode(QState::ExclusiveStates);
    m_groupStateWork->setInitialState(m_stateHistoryWork);
    m_machine.setInitialState(m_idleState);
}

void WorkMachine::initStateTrans()
{
    m_groupStateWork->addTransition(this, &WorkMachine::sigPauseMachine, m_statePause);
    m_statePause->addTransition(this, &WorkMachine::sigResumeMachine, m_stateHistoryWork);

    connect(m_workThread, &WorkThread::finished, this, [this](){
        if (m_isPause) {

        }
        else {
            emit sigNextState();
        }
    });

    m_idleState->addTransition(this, &WorkMachine::sigNextState, m_stateOpen);
    //m_stateOpen->addTransition(this, &WorkMachine::sigNextState, m_stateClose);
    m_stateOpen->addTransition(m_stateOpen, &QState::finished, m_stateClose);
    m_stateClose->addTransition(this, &WorkMachine::sigNextState, m_stateWash);
    m_stateWash->addTransition(this, &WorkMachine::sigNextState, m_stateDry);
    m_stateDry->addTransition(this, &WorkMachine::sigNextState, m_idleState);
}

void WorkMachine::initWork()
{
    connect(m_idleState, &QState::entered, this, [this](){
        qDebug() << "init state";
    });

    connect(m_stateHistoryWork, &QState::entered, this, [this](){
        qDebug() << "m_stateHistoryWork state enter";
    });

    connect(m_stateOpen, &QState::entered, this, [this](){
        m_workThread->startTask("step 1 Open");
    });

    connect(m_stateClose, &QState::entered, this, [this](){
        m_workThread->startTask("step 2 Close");
    });

    connect(m_groupStateWork, &QState::entered, this, [this](){
        qDebug() << "Work state enter";
    });

    connect(m_stateWash, &QState::entered, this, [this](){
        m_workThread->startTask("step 3 Wash", 2000);
    });

    connect(m_stateDry, &QState::entered, this, [this](){
        m_workThread->startTask("step 4 Dry", 2000);
    });

    connect(m_statePause, &QState::entered, this, [this](){
        qDebug() << "pause";
    });
}

cpp 复制代码

#ifndef WORKTHREAD_H
#define WORKTHREAD_H

#include <QObject>
#include <QThread>

class WorkThread: public QThread
{
public:
    WorkThread();
    void startTask(QString log, int timems=500);
    void run() override;

private:
    QString   m_log;
    int       m_time;
};

#endif // WORKTHREAD_H

cpp 复制代码

#include "WorkThread.h"
#include <QDebug>

WorkThread::WorkThread() {

}

void WorkThread::startTask(QString log, int timems)
{
    m_log = log;
    m_time = timems;
    this->start();
}

void WorkThread::run()
{
    QThread::msleep(100);
    qDebug() << m_log  + " start running ...";

    QThread::msleep(m_time);
    qDebug() << m_log  + " end";
}

UI 控制类

cpp 复制代码

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include "WorkMachine.h"

QT_BEGIN_NAMESPACE
namespace Ui {
class Widget;
}
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget(QWidget *parent = nullptr);
    ~Widget();

private slots:
    void on_btnRun_clicked();

private:
    Ui::Widget *ui;
    WorkMachine  m_machine;
};
#endif // WIDGET_H

cpp 复制代码

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);

    connect(ui->btnStart, &QPushButton::clicked, this, [this](){
        m_machine.startMachine();
    });

    connect(ui->btnPause, &QPushButton::clicked, this, [this](){
        m_machine.pauseMachine();
    });

    connect(ui->btnResume, &QPushButton::clicked, this, [this](){
        m_machine.resumeMachine();
    });

    connect(&m_machine, &WorkMachine::sigMachineState, this, [this](bool isRun){
        ui->btnPause->setEnabled(isRun);
    });
}

Widget::~Widget()
{
    delete ui;
}

void Widget::on_btnRun_clicked()
{
    m_machine.runMachineWorkFlow();
}

设计思路：

1 .每个状态对应一个流程

每个状态进入后开始执行流程动作
状态进入流程开始执行，执行结束线程结束
线程结束信号控制转移到下一个状态，也就是下一个流程继续往下走
暂停时候主动触发 pause 信号状态机从 work 状态跳出到 pause 状态
恢复时候从 pause 状态回到 history 状态，根据需要设置历史状态深浅，是否记录子状态，还是只记录第一层状态
每个子状态流程末尾使用 final 状态标记，使用他的finished 信号进行状态转移
每个子状态设置初始状态，也就是子状态第一个状态