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使用该程序我按下“运行”按钮和用于循环周期100次（具有100毫秒的延迟） 并打印在一个txt字段做的QThread-ING“正确”的方式
我循环计数已经成功完成了从QThread派生的MyThread对象。有用。我可以 用'停止'按钮中断循环。
但是，严正警告说从QThread派生一个对象非常糟糕。所以我做了 他们建议的另一种方式，即“正确”的方式。
它不起作用。我可以在控制台上获取循环周期编号，但不能在文本框中输入
“运行”按钮关闭，直到完成100次循环后再次出现。 而文本字段显示99.
这是代码，我做错了什么？
// MyWidget.h SF022
#ifndef MYWIDGET_H_
#define MYWIDGET_H_
#include <QtWidgets/QWidget>
#include <QtWidgets/QLineEdit>
#include <QtWidgets/QPushButton>
#include "../MyThread.h"
#include "../MyObject.h"
#include <QThread>
class MyWidget : public QWidget {
Q_OBJECT
public:
MyWidget(QWidget* parent = 0);
~MyWidget();
QPushButton* pbRun;
QPushButton* pbStop;
QPushButton* pbExit;
QLineEdit* txtCount;
QThread* cThread;
MyObject* myObject;
public slots:
void onNumberChanged(int);
private slots:
void pbRun_Slot();
void pbStop_Slot();
void pbExit_Slot();
};
#endif /* MYWIDGET_H_ */
------------------------------------------------
// MyWidget.cpp
#include "MyWidget.h"
#include "../K.h"
#include <iostream>
MyWidget::MyWidget(QWidget* parent) : QWidget(parent) {
pbRun = new QPushButton(this);
pbRun->setObjectName(QStringLiteral("pbRun"));
pbRun->setGeometry(QRect(20, 20, 80, 40));
pbRun->setText("Run");
connect(pbRun, SIGNAL(clicked()), this, SLOT(pbRun_Slot()));
pbStop = new QPushButton(this);
pbStop->setObjectName(QStringLiteral("pbStop"));
pbStop->setGeometry(QRect(20, 80, 80, 40));
pbStop->setText("Stop");
connect(pbStop, SIGNAL(clicked()), this, SLOT(pbStop_Slot()));
pbExit = new QPushButton(this);
pbExit->setObjectName(QStringLiteral("pbExit"));
pbExit->setGeometry(QRect(20, 140, 80, 40));
pbExit->setText("Exit");
connect(pbExit, SIGNAL(clicked()), this, SLOT(pbExit_Slot()));
txtCount = new QLineEdit(this);
txtCount->setGeometry(QRect(20, 200, 80, 40));
txtCount->setStyleSheet("QLineEdit{background: white;}");
// myObject holds the cycling mechanism
myObject = new MyObject(this);
// the myObject sends each new cycle number out here
connect(myObject, SIGNAL(numberChanged(int)), this, SLOT(onNumberChanged(int)));
}
MyWidget::~MyWidget() {
}
void MyWidget::pbRun_Slot() {
// start thread
cThread = new QThread(this);
myObject->doSetup(*cThread);
myObject->moveToThread(cThread);
cThread->start();
}
void MyWidget::pbStop_Slot() {
// stop the thread
myObject->Stop = true;
}
void MyWidget::pbExit_Slot() {
// a static pointer to the main window
(K::SfMainWin)->close();
}
// a slot
void MyWidget::onNumberChanged(int j) {
// output the cycle count to a text field
txtCount->setText(QString::number(j));
}
----------------------------------------------------------
// MyObject.h
#ifndef MYOBJECT_H_
#define MYOBJECT_H_
#include <QObject>
#include <QThread>
class MyObject : public QObject {
Q_OBJECT
public:
explicit MyObject(QObject* parent = 0);
~MyObject();
void doSetup(QThread&);
bool Stop;
signals:
void numberChanged(int);
public slots:
void doWork();
};
#endif /* MYOBJECT_H_ */
----------------------------------------------------------
// MyObject.cpp
#include "MyObject.h"
#include <QMutex>
#include <iostream>
#include "string.h"
MyObject::MyObject(QObject* parent) : QObject(parent) {
Stop = false;
}
MyObject::~MyObject() {
}
void MyObject::doSetup(QThread& cThread) {
Stop = false;
connect(&cThread, SIGNAL(started()), this, SLOT(doWork()));
}
void MyObject::doWork() {
for (int i = 0; i < 100; i++) {
QMutex mutex;
mutex.lock();
if (this->Stop) {
break;
}
// output into a text field
emit numberChanged(i);
// output on the console
std::cout << "running " << (QString::number(i)).toStdString() << std::endl;
mutex.unlock();
QThread::msleep(100);
}
}
看一看以下链接一些见解：https://mayaposch.wordpress.com/2011/11/01/how-to-really-truly-use-qthreads-the-full-explanation/ – 2015-01-26 20:23:27
如果这只是一个练习，那么确定，但通常你会用'QTimer'来做这样的事情，而不需要工作线程。阅读[this]（http://qt-project.org/wiki/Threads_Events_QObjects#c2e33c61ced29e1eb1bee9a1671f202e）了解更多信息。 – thuga 2015-01-27 08:39:34