qgsdelimitedtextplugingui.cpp

一个非常好的GIS开源新版本

/***************************************************************************
 *   Copyright (C) 2004 by Gary Sherman                                    *
 *   sherman at mrcc.com                                                   *
 *                                                                         *
 *   GUI for loading a delimited text file as a layer in QGIS              *
 *   This plugin works in conjuction with the delimited text data          *
 *   provider plugin                                                       *
 *                                                                         *
 *   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.                                   *
 ***************************************************************************/
/* $Id: qgsdelimitedtextplugingui.cpp 8221 2008-03-14 13:30:14Z mhugent $ */
#include <iostream>
#include "qgsdelimitedtextplugingui.h"
#include "qgscontexthelp.h"

#include "qgisinterface.h"

#include <QFileDialog>
#include <QFile>
#include <QComboBox>
#include <QSettings>
#include <QFileInfo>
#include <QRegExp>
#include <QMessageBox>
#include <QTextStream>

QgsDelimitedTextPluginGui::QgsDelimitedTextPluginGui(QgisInterface * _qI, QWidget * parent, Qt::WFlags fl) 
: QDialog(parent, fl), qI(_qI)
{
  setupUi(this);
  pbnOK = buttonBox->button(QDialogButtonBox::Ok);
  pbnParse = buttonBox->addButton(tr("Parse"), QDialogButtonBox::ActionRole);
  connect(pbnParse, SIGNAL(clicked()), this, SLOT(pbnParse_clicked()));
  connect(txtFilePath, SIGNAL(textChanged(const QString&)), this, SLOT(pbnParse_clicked()));
  enableButtons();
  // at startup, fetch the last used delimiter and directory from
  // settings
  QSettings settings;
  QString key = "/Plugin-DelimitedText";
  txtDelimiter->setText(settings.readEntry(key + "/delimiter"));

  // and how to use the delimiter
  QString delimiterType = settings.value(key + "/delimiterType",
                                         "plain").toString();
  if (delimiterType == "plain")
  {
    delimiterPlain->setChecked(true);
    delimiterRegexp->setChecked(false);
  }
  else
  {
    delimiterPlain->setChecked(false);
    delimiterRegexp->setChecked(true);
  }

  QString format = QString("<h2>%1</h2><p>%2</p><p>%3</p>");
  QString header = tr("Description");
  QString paragraph1 = tr("Select a delimited text file containing a header row"
			  " and one or more rows of x and y coordinates that you"
			  " would like to use as a point layer and this plugin will do the job for you!");
  QString paragraph2 = tr("Use the layer name box to specify the legend name for the new layer."
			  " Use the delimiter box to specify what delimeter is used in your file (e.g. space,"
			  " comma, tab or a regular expression in Perl style). After choosing a delimiter,"
			  " press the parse button and select the columns containing the x and y values for the layer.");
  teInstructions->setHtml(format.arg(header)
			  .arg(paragraph1)
			  .arg(paragraph2));

  txtSample->setFixedHeight(120);
}  
QgsDelimitedTextPluginGui::~QgsDelimitedTextPluginGui()
{
}
/** Autoconnected slots **/
void QgsDelimitedTextPluginGui::on_buttonBox_helpRequested()
{
  QgsContextHelp::run(context_id);
}
void QgsDelimitedTextPluginGui::on_btnBrowseForFile_clicked()
{
  getOpenFileName();
}
void QgsDelimitedTextPluginGui::pbnParse_clicked()
{
  updateFieldLists();
}
void QgsDelimitedTextPluginGui::on_buttonBox_accepted()
{
  if(txtLayerName->text().length() > 0)
  {
    //Build the delimited text URI from the user provided information
      QString delimiterType = "plain";
      if (delimiterRegexp->isChecked())
        delimiterType = "regexp";

    QString uri = QString("%1?delimiter=%2&delimiterType=%3&xField=%4&yField=%5")
      .arg(txtFilePath->text())
      .arg(txtDelimiter->text())
      .arg(delimiterType)
      .arg(cmbXField->currentText())
      .arg(cmbYField->currentText());

    // add the layer to the map
    emit drawVectorLayer(uri,txtLayerName->text(),"delimitedtext");
    // store the settings

    QSettings settings;
    QString key = "/Plugin-DelimitedText";
    settings.writeEntry(key + "/delimiter", txtDelimiter->text());
    QFileInfo fi(txtFilePath->text());
    settings.writeEntry(key + "/text_path", fi.dirPath());

    if (delimiterPlain->isChecked())
      settings.setValue(key + "/delimiterType", "plain");
    else
      settings.setValue(key + "/delimiterType", "regexp");

    accept();
  }
  else
  {
    QMessageBox::warning(this, tr("No layer name"), tr("Please enter a layer name before adding the layer to the map"));
  }
} 

void QgsDelimitedTextPluginGui::on_buttonBox_rejected()
{
  reject();
}

void QgsDelimitedTextPluginGui::updateFieldLists()
{
  // Update the x and y field dropdown boxes
#ifdef QGISDEBUG  
  std::cerr << "Updating field lists" << std::endl;
#endif
  // open the file

  if(QFile::exists(txtFilePath->text())){
    QFile *file = new QFile(txtFilePath->text());
    if ( file->open( QIODevice::ReadOnly ) ) {
      // clear the field lists
      cmbXField->clear();
      cmbYField->clear();
      QTextStream stream( file );
      QString line;
      line = stream.readLine(); // line of text excluding '\n'
      if(txtDelimiter->text().length() > 0)
      {
#ifdef QGISDEBUG
        std::cerr << "Attempting to split the input line: " << line.toLocal8Bit().data() <<
          " using delimiter " << txtDelimiter->text().toLocal8Bit().data() << std::endl;
#endif
        QString delimiter = txtDelimiter->text();
        
        QStringList fieldList;

        if (delimiterPlain->isChecked())
        {
          // convert \t to tabulator
          delimiter.replace("\\t", "\t");
          fieldList = line.split(delimiter);
        }
        else
        {
          QRegExp del(delimiter);
          fieldList = line.split(QRegExp(delimiter));
        }

#ifdef QGISDEBUG
        std::cerr << "Split line into " << fieldList.size() << " parts" << std::endl; 
#endif
        //
        // We don't know anything about a text based field other
        // than its name. All fields are assumed to be text
        for ( QStringList::Iterator it = fieldList.begin(); it != fieldList.end(); ++it ) {
          // add item to both drop-downs (X field and Y field)
          if((*it).length() > 0)
          {
            cmbXField->insertItem(*it);
            cmbYField->insertItem(*it);
          }
        }  
        // Have a go at setting the selected items in the X and Y
        // combo boxes to something sensible.
        int indexX = cmbXField->findText("lon", Qt::MatchContains);
        int indexY = cmbXField->findText("lat", Qt::MatchContains);
        if (indexX != -1 && indexY != -1)
        {
          cmbXField->setCurrentIndex(indexX);
          cmbYField->setCurrentIndex(indexY);
        }
        else
        {
          indexX = cmbXField->findText("x", Qt::MatchContains);
          indexY = cmbXField->findText("y", Qt::MatchContains);
          if (indexX != -1 && indexY != -1)
          {
            cmbXField->setCurrentIndex(indexX);
            cmbYField->setCurrentIndex(indexY);
          }
        }
        // enable the buttons
        enableButtons();
      }
      else
      {
        QMessageBox::warning(this, tr("No delimiter"),tr("Please specify a delimiter prior to parsing the file"));
      }
      // clear the sample text box
      txtSample->clear();
      // put the header row in the sample box
      txtSample->insert(line + "\n"); 
      // put a few more lines into the sample box
      int counter = 0;
      while (
              (!(line=stream.readLine()).isEmpty()) && 
              (counter < 20)
            )
      {
        txtSample->insert(line + "\n");
        counter++;
      }
      // close the file
      file->close();
      // put a default layer name in the text entry
      QFileInfo finfo(txtFilePath->text());
      txtLayerName->setText(finfo.completeBaseName());
    }

  }

}
void QgsDelimitedTextPluginGui::getOpenFileName()
{
  // Get a file to process, starting at the current directory
  // Set inital dir to last used
  QSettings settings;

  QString s = QFileDialog::getOpenFileName(
      this,
      tr("Choose a delimited text file to open"),
      settings.readEntry("/Plugin-DelimitedText/text_path","./"),
      "Text files (*.txt *.csv);; All files (* *.*)");

  // set path
  txtFilePath->setText(s);
  // update the field drop-down boxes by parsing and splitting
  // the header row
  updateFieldLists();
}
void QgsDelimitedTextPluginGui::enableButtons()
{
  pbnParse->setEnabled(txtDelimiter->text().length() > 0 && txtFilePath->text().length() > 0);
  pbnOK->setEnabled(txtDelimiter->text().length() > 0 && txtFilePath->text().length() > 0);
}
void QgsDelimitedTextPluginGui::help()
{
  qI->openURL("plugins/delimited_text/index.html",true);
}

void QgsDelimitedTextPluginGui::on_txtDelimiter_textChanged(const QString & text)
{
  if(!text.isEmpty())
    {
      pbnParse->setEnabled(true);
    }
}