Question

例如，当您按“Esc”时，应用程序结束。

Answer 1

这是针对linux的解决方法。使用这些帖子

Capture characters from standard input without waiting for enter to be pressed https://stackoverflow.com/a/912796/2699984

我是这样做的：

<强> ConsoleReader.h

#ifndef CONSOLEREADER_H
#define CONSOLEREADER_H

#include <QThread>

class ConsoleReader : public QThread
{
    Q_OBJECT
signals:
    void KeyPressed(char ch);
public:
   ConsoleReader();
   ~ConsoleReader();
   void run();
};

#endif  /* CONSOLEREADER_H */

<强> ConsoleReader.cpp

#include "ConsoleReader.h"
#include <stdio.h>
#include <unistd.h>
#include <termios.h>

static struct termios oldSettings;
static struct termios newSettings;

/* Initialize new terminal i/o settings */
void initTermios(int echo) 
{
  tcgetattr(0, &oldSettings); /* grab old terminal i/o settings */
  newSettings = oldSettings; /* make new settings same as old settings */
  newSettings.c_lflag &= ~ICANON; /* disable buffered i/o */
  newSettings.c_lflag &= echo ? ECHO : ~ECHO; /* set echo mode */
  tcsetattr(0, TCSANOW, &newSettings); /* use these new terminal i/o settings now */
}

/* Restore old terminal i/o settings */
void resetTermios(void) 
{
  tcsetattr(0, TCSANOW, &oldSettings);
}

/* Read 1 character without echo */
char getch(void) 
{
  return getchar();
}

ConsoleReader::ConsoleReader()
{
  initTermios(0);
}

ConsoleReader::~ConsoleReader()
{
  resetTermios();
}

void ConsoleReader::run()
{
    forever
    {
        char key = getch();        
        emit KeyPressed(key);
    }
}

然后只需启动新线程来读取密钥：

ConsoleReader *consoleReader = new ConsoleReader();
connect (consoleReader, SIGNAL (KeyPressed(char)), this, SLOT(OnConsoleKeyPressed(char)));
consoleReader->start();

*更新（在退出时添加了恢复终端设置）

Answer 2

Qt不处理控制台事件，只能从控制台读取\n - 终止的行。

您需要使用本机API或其他库（curses）。

Answer 3

如果您只需要退出＆＃39;也许下面的代码片段会有所帮助（需要c ++ 11和qt5）：

#include <iostream>
#include <future>

#include <QCoreApplication>
#include <QTimer>

int main(int argc, char *argv[])
{
    QCoreApplication application(argc, argv);
    bool exitFlag = false;

    auto f = std::async(std::launch::async, [&exitFlag]{
        std::getchar();
        exitFlag = true;
    });

    QTimer exitTimer;
    exitTimer.setInterval(500);
    exitTimer.setSingleShot(false);

    QObject::connect(&exitTimer,
                     &QTimer::timeout,
                     [&application,&exitFlag] {
        if (exitFlag)
            application.quit();
    });

    exitTimer.start();

    std::cout << "Started! Press Enter to quit...";
    int ret =  application.exec();
    f.wait();
    return ret;
}

如何处理Qt控制台应用程序中的按键事件？

3 个答案: