将std :: cout重定向到QTextEdit

问题描述

我是Qt应用程序开发的新手，我非常感谢您的帮助。这是
的重新发布

I'm new to Qt application development, I would appreciate your help. This is a re-post ofredirect std::cout to QTextEdit

我试图将 std :: cout 重定向到 QTextEdit ，我看到并试图测试下面的链接提供的示例。

I'm trying to redirect std::cout to a QTextEdit and I've seen and tried to test the example provided in the following link.

参考链接1：

使用Qt Creator 2.4 .1从参考链接1测试示例。

Using Qt Creator 2.4.1 to test the example from Reference Link 1.

untiled1.pro

untiled1.pro

SOURCES += \
main.cpp
HEADERS += \
qdebugstream.h

qdebugstream.h

qdebugstream.h

    #ifndef QDEBUGSTREAM_H
#define QDEBUGSTREAM_H

#include <iostream>
#include <streambuf>
#include <string>

#include "qtextedit.h"

class QDebugStream : public std::basic_streambuf<char>
{
public:
 QDebugStream(std::ostream &stream, QTextEdit* text_edit) : m_stream(stream)
 {
  log_window = text_edit;
  m_old_buf = stream.rdbuf();
  stream.rdbuf(this);
 }
 ~QDebugStream()
 {
  // output anything that is left
  if (!m_string.empty())
   log_window->append(m_string.c_str());

  m_stream.rdbuf(m_old_buf);
 }

protected:
 virtual int_type overflow(int_type v)
 {
  if (v == '\n')
  {
   log_window->append(m_string.c_str());
   m_string.erase(m_string.begin(), m_string.end());
  }
  else
   m_string += v;

  return v;
 }

 virtual std::streamsize xsputn(const char *p, std::streamsize n)
 {
  m_string.append(p, p + n);

  int pos = 0;
  while (pos != std::string::npos)
  {
   pos = m_string.find('\n');
   if (pos != std::string::npos)
   {
    std::string tmp(m_string.begin(), m_string.begin() + pos);
    log_window->append(tmp.c_str());
    m_string.erase(m_string.begin(), m_string.begin() + pos + 1);
   }
  }

  return n;
 }

private:
 std::ostream &m_stream;
 std::streambuf *m_old_buf;
 std::string m_string;


  QTextEdit* log_window;
    };

#endif

main.cpp

#include "qdebugstream.h"
#include "qtextedit.h"
#include <QtGui>

int main(int argc, char **argv)
{
    QApplication application(argc, argv);
       application.connect(&application, SIGNAL(lastWindowClosed()),
    &application, SLOT(quit()));

       QMainWindow* mainWindow = new QMainWindow();

       QTextEdit* myTextEdit = new QTextEdit(mainWindow, "myTextEdit");
       myTextEdit->setTextFormat(Qt::LogText);
       QDebugStream qout(std::cout, myTextEdit);

       mainWindow->show();
       std::cout << "Send this to the Text Edit!" << std::endl;

       return application.exec();
}

我收到以下错误消息：

C：\Documents和
Settings\Administrator\untitled1-build-desktop-Qt_4_8_1_for_Desktop _- MSVC2010 _Qt_SDK__Debug..\untitled1\main.cpp：14：错误：C2039：'setTextFormat'：不是'QTextEdit'的成员

C:\Documents and Settings\Administrator\untitled1-build-desktop-Qt_4_8_1_for_Desktop_-MSVC2010_Qt_SDK__Debug..\untitled1\main.cpp:14: error: C2039: 'setTextFormat' : is not a member of 'QTextEdit'

c：\qtsdk\desktop\qt\4.8.1\ msvc2010 \include\qtgui\qtextedit.h：70：see
'QTextEdit'的声明

c:\qtsdk\desktop\qt\4.8.1\msvc2010\include\qtgui\qtextedit.h:70: see declaration of 'QTextEdit'

推荐答案

查看， QTextEdit 有两个构造函数，

Looking at the documentation, QTextEdit has two constructors,

QTextEdit::QTextEdit ( QWidget * parent = 0 )

和

QTextEdit::QTextEdit ( const QString & text, QWidget * parent = 0 )

尝试更改

QTextEdit* myTextEdit = new QTextEdit(mainWindow, "myTextEdit");

到

QTextEdit* myTextEdit = new QTextEdit(mainWindow);

这不会解决所有的问题，因为仍然有地方使用旧的Qt3 API。您需要根据需要进行更改。

This won't fix all the problems, since there are still places that use the old Qt3 API. You'll need to make changes as necessary.

这篇关于将std :: cout重定向到QTextEdit的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！