有關 QThread 多次執行程式

LeonSu

Hello

想請問一下，有關使用QThread 重覆執行同一個代碼。
簡單的程式如下：

//------------------------------------work.h-------------------------------------------

class work : public QObject
{
    Q_OBJECT
public:
    explicit work(QObject *parent = nullptr);
    void setinitialvalue(int value);

signals:
    void finish();
    void sentresult(int);
public slots:

    void dosomething();

private:
    int result;
};

//-----------------------work.cpp---------------------------------

work::work(QObject *parent) : QObject(parent)
{
    result = 0;
}


void work::dosomething()
{

    for(int k = 0; k < 10; k++)
        ++result;

    emit sentresult(result);
    emit finish();
}

void work::setinitialvalue(int value)
{
    result = value;
}

//-----------------------------------mainwindows.h-----------------------

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
    void getreault(int data);
    void GoStart();

private:
    Ui::MainWindow *ui;
    QThread *thread;
    work *dowork;
    int initialvalue;
};

//------------------------------------mainwindows.cpp---------------------

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

    initialvalue = 0;

    thread = new QThread();
    dowork = new work();

    dowork->moveToThread(thread);
    connect(thread, SIGNAL(started()), dowork, SLOT(dosomething()));
    connect(dowork, SIGNAL(finish()), thread, SLOT(deleteLater()));
    connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
    connect(dowork, SIGNAL(sentresult(int)), this, SLOT(getreault(int)));

    connect(ui->go_pb, SIGNAL(clicked(bool)), this, SLOT(GoStart()));
}

MainWindow::~MainWindow()
{
    delete thread;
    delete dowork;
    delete ui;
}


void MainWindow::getreault(int data)
{
    qDebug() << data;
}

void MainWindow::GoStart()
{
    ++initialvalue;
    dowork->setinitialvalue(initialvalue);
    thread->start();
}

我按了第一次按鈕，程式會執行，但是無法再進行第二次的執行。
請問有什麼方法以QThread多次執行，但不是同時。

謝謝！

ytexas

@LeonSu said in 有關 QThread 多次執行程式:

connect(dowork, SIGNAL(finish()), thread, SLOT(deleteLater()));

Hi~
其实本可以多次点击start,多次执行,但是问题在于dosomething()中的发出的finish信号触发了thread.deleteLater(),导致thread销毁. 即
connect(dowork, SIGNAL(finish()), thread, SLOT(deleteLater()));
建议在MainWindow关闭时,再释放thread.

另一种方法则是在点击开始时,再创建一个thread,并重新链接信号与槽.

以上,希望能帮助到您 :D