How to generate TOC using DOM traversal

kalma

Qt 5.3.0, win7

Hi
Am trying to generate an hierarchical TOC of my html docs embedded in my application's resource tree and later to view the contents using QTreeView; the DOM traversal example does that for the whole html document structure; I want this done only for <h1><h2><h3>, it sounds tricky "recursive" as I could only extract one level for now using the following code:

@
QStandardItemMode *TOCModel = new QStandardItemMode(this);
QStandardItem *parentItem = TOCModel->invisibleRootItem();
QWebFrame *frame = ui->webView->page()->mainFrame();
QWebElementCollection subtitles = frame->findAllElements("h4");
foreach (QWebElement element, subtitles) {
QStandardItem *item = new QStandardItem(element.toPlainText());
parentItem->appendRow(item);
}
ui->treeView->setModel(TOCModel );
@

Is there any hints or perhaps sample of how to do that in less painful way?

jazzycamel

You do need to do DOM traversal. The full working example below does what you want (naively) using the QtXml framework:

HTML_TOC.pro
@
QT += core gui xml

TARGET = HTML_TOC
TEMPLATE = app

SOURCES += main.cpp
widget.cpp

HEADERS += widget.h
@

widget.h
@
#ifndef WIDGET_H
#define WIDGET_H

#include <QtGui/QWidget>

class QStandardItemModel;
class QTreeView;

class Widget : public QWidget
{
Q_OBJECT

public:
Widget(QWidget *parent = 0);
~Widget();

private:
QStandardItemModel *model;
QTreeView *treeView;
};

#endif // WIDGET_H
@

widget.cpp
@
#include "widget.h"

#include <QtGui>
#include <QtCore>
#include <QtXml>

Widget::Widget(QWidget *parent)
: QWidget(parent)
{
QString html=
"<!DOCTYPE html>\n"
"<html>"
" <head>"
" <title>Document</title>"
" </head>"
" <body>"
" <h1>Document</h1>"
" <p>Some text.</p>"
" <h2>Sub Heading Level 2</h2>"
" <p>Some more text.</p>"
" <h3>Sub Heading Level 3</h3>"
" <p>Yet more text.</p>"
" <h2>Another Sub Heading Level 2</h2>"
" <p>Some final text.</p>"
" </body>"
"</html>";

QDomDocument document;
QString errorMsg;
int errorLine, errorColumn;
bool ok=document.setContent(html, false, &errorMsg, &errorLine, &errorColumn);
if(!ok){
    qDebug() << "Parse Failure:" << errorMsg << errorLine << errorColumn;
    return;
}

model=new QStandardItemModel(this);
QStandardItem *parentItem=model->invisibleRootItem();

QDomNodeList bodyElements=document.elementsByTagName("body");
QDomNode body=bodyElements.at(0);
Q_ASSERT(body.nodeName()=="body");

int headingLevel=1;
QDomElement heading=body.firstChildElement("h1");

while(!heading.isNull()){
    QStandardItem *item=new QStandardItem(heading.firstChild().nodeValue());
    parentItem->appendRow(item);

    QDomElement next=heading.nextSiblingElement(QString("h%1").arg(headingLevel+1));
    if(!next.isNull()) {
        headingLevel+=1;
        parentItem=item;
    }
    else{
        next=heading.nextSiblingElement(QString("h%1").arg(headingLevel));
        if(next.isNull()&&headingLevel>1){
            headingLevel-=1;
            next=heading.nextSiblingElement(QString("h%1").arg(headingLevel));
            parentItem=parentItem->parent();
        }
    }
    heading=next;
}

treeView=new QTreeView(this);
treeView->setModel(model);

QVBoxLayout *l=new QVBoxLayout(this);
l->addWidget(treeView);

}

Widget::~Widget(){}
@

main.cpp
@
#include <QtGui/QApplication>
#include "widget.h"

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Widget w;
w.show();

return a.exec&#40;&#41;;

}
@

Hope this helps ;o)

kalma

Hi jazzycamel

This is generous!
Thank you very much.