subclassing - qthread 中的睡眠调用会阻塞 UI 线程

Question

您好我正在 QT 4.6.2 中实现一个简单的线程 GUI 应用程序。我正在使用 QThread 而不对其进行子类化。我在 start() 函数中调用了 usleep() 函数，但这会导致 GUI 冻结。我该如何解决这个问题。下面是代码

#ifndef ECGREADER_H
#define ECGREADER_H
#include<QObject>
class ecgreader : public QObject
{
    Q_OBJECT

public:
    ecgreader(QObject *parent=0);
    ~ecgreader();
public Q_SLOTS:
    void start();
Q_SIGNALS:
    void finished();
};
#endif // ECGREADER_H

下面是 start() 函数

void ecgreader::start()
{
   int i= system("ls>output.txt");
   SLEEP(10000);
   if(i==0)
   {
       emit finished();
   }
}

终于在这里发出了开始的电话

void Application::onbtnclicked()
{
    QThread* thread=new QThread;
    ecgreader* reader=new ecgreader;
    reader->moveToThread(thread);
    connect(thread,SIGNAL(started()),reader,SLOT(start()));
    connect(reader,SIGNAL(finished()),thread,SLOT(quit()));
    connect(reader,SIGNAL(finished()),reader,SLOT(deleteLater()));
    connect(reader,SIGNAL(finished()),thread,SLOT(deleteLater()));
    reader->start();
}

请帮忙

Answer 1

您有两个问题：首先您创建了线程，但您从未启动它。其次，您直接在阅读器上调用 start() 而不是发出信号。

我认为您的意思是调用 thread->start() 而不是 reader->start()：

void Application::onbtnclicked()
{
    QThread* thread=new QThread;
    ecgreader* reader=new ecgreader;
    reader->moveToThread(thread);
    connect(thread,SIGNAL(started()),reader,SLOT(start()));
    connect(reader,SIGNAL(finished()),thread,SLOT(quit()));
    connect(reader,SIGNAL(finished()),reader,SLOT(deleteLater()));
    connect(reader,SIGNAL(finished()),thread,SLOT(deleteLater()));
    thread->start();
}