api/2.18/qgscontexthelp_8cpp_source.html

 /***************************************************************************
                           qgscontexthelp.cpp
                     Display context help for a dialog
                              -------------------
     begin                : 2005-06-19
     copyright            : (C) 2005 by Gary E.Sherman
     email                : sherman at mrcc.com
  ***************************************************************************/

 /***************************************************************************
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
  *   it under the terms of the GNU General Public License as published by  *
  *   the Free Software Foundation; either version 2 of the License, or     *
  *   (at your option) any later version.                                   *
  *                                                                         *
  ***************************************************************************/

 #include <QString>
 #include <QProcess>
 #include <QTextStream>

 #include "qgscontexthelp.h"
 #include "qgsmessagelog.h"
 #include "qgsapplication.h"
 #include "qgslogger.h"


 QgsContextHelp *QgsContextHelp::gContextHelp = nullptr;  // Singleton instance

 void QgsContextHelp::run( const QString& context )
 {
   if ( !gContextHelp )
   {
     // Create singleton instance if it does not exist
     gContextHelp = new QgsContextHelp();
   }

   gContextHelp->showContext( context );
 }

 QgsContextHelp::QgsContextHelp()
 {
   mProcess = start();
 }

 QgsContextHelp::~QgsContextHelp()
 {
   delete mProcess;
 }

 QProcess *QgsContextHelp::start()
 {
   // Get the path to the help viewer
   QString helpPath = QgsApplication::helpAppPath();
   QgsDebugMsg( QString( "Help path is %1" ).arg( helpPath ) );

   QProcess *process = new QProcess;

   // Delete this object if the process terminates
   connect( process, SIGNAL( finished( int, QProcess::ExitStatus ) ), SLOT( processExited() ) );

   connect( process, SIGNAL( error( QProcess::ProcessError ) ), this, SLOT( error( QProcess::ProcessError ) ) );

 #ifdef Q_OS_WIN
   if ( QgsApplication::isRunningFromBuildDir() )
   {
     process->setEnvironment( QStringList() << QString( "PATH=%1;%2" ).arg( getenv( "PATH" ) ).arg( QApplication::applicationDirPath() ) );
   }
 #endif

   process->start( helpPath, QStringList() );

   return process;
 }

 void QgsContextHelp::error( QProcess::ProcessError error )
 {
   QgsMessageLog::logMessage( tr( "Error starting help viewer [%1]" ).arg( error ), tr( "Context help" ) );
 }

 void QgsContextHelp::showContext( const QString& context )
 {
   init();

   QString helpContents = gContextHelpTexts.value( context,
                          tr( "<h3>Oops! QGIS can't find help for this form.</h3>"
                              "The help file for %1 was not found for your language<br>"
                              "If you would like to create it, contact the QGIS development team"
                            ).arg( context ) );

   QString myStyle = QgsApplication::reportStyleSheet();
   helpContents = "<head><style>" + myStyle + "</style></head><body>" + helpContents + "</body>\nEOH\n";

   mProcess->write( helpContents.toUtf8() );
 }

 void QgsContextHelp::processExited()
 {
   // Delete this object if the process terminates
   delete gContextHelp;
   gContextHelp = nullptr;
 }
qgscontexthelp.h

QgsDebugMsg
#define QgsDebugMsg(str)
Definition: qgslogger.h:33

QgsApplication::isRunningFromBuildDir
static bool isRunningFromBuildDir()
Indicates whether running from build directory (not installed)
Definition: qgsapplication.h:317

QgsApplication::reportStyleSheet
static QString reportStyleSheet()
get a standard css style sheet for reports.
Definition: qgsapplication.cpp:936

QObject::tr
QString tr(const char *sourceText, const char *disambiguation, int n)

QgsContextHelp::run
static void run(const QString &context)
Definition: qgscontexthelp.cpp:31

QgsContextHelp
Provides a context based help browser for a dialog.
Definition: qgscontexthelp.h:35

QProcess

QgsApplication::helpAppPath
static QString helpAppPath()
Returns the path to the help application.
Definition: qgsapplication.cpp:602

qgsmessagelog.h

qgsapplication.h

QgsMessageLog::logMessage
static void logMessage(const QString &message, const QString &tag=QString::null, MessageLevel level=WARNING)
add a message to the instance (and create it if necessary)
Definition: qgsmessagelog.cpp:43

QProcess::setEnvironment
void setEnvironment(const QStringList &environment)

QString

QStringList

QHash::value
const T value(const Key &key) const

QIODevice::write
qint64 write(const char *data, qint64 maxSize)

QObject::connect
bool connect(const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type)

QCoreApplication::applicationDirPath
QString applicationDirPath()

QProcess::start
void start(const QString &program, const QStringList &arguments, QFlags< QIODevice::OpenModeFlag > mode)

qgslogger.h