Sphinx Integration in Qt - html

I would like to integrate Sphinx documentation functionality to help with my Qt project. However, when including the HTML files for Sphinx, the formatting appears differently and no file links work. For example:
QFile file("/home/user1/project/Sphinx/build/html/intro.html");
if (!file.open(QIODevice::Readonly))
qDebug() << "Didn't open file";
QTextStream in(&file);
ui->textBrowser->setText(in.readAll());
Error: QTextBrowser: No document for _sources/intro.txt
This will cause the textBrowser to open the correct file, but will not end up displaying the page with the correct HTML coding, and will not follow the links even though those HTML files are contained in the same path (as I have copied the entire Sphinx project into the Qt project).
Is there some way to package the entire Sphinx project so that inclusion of multiple files is unnecessary or is the multiple file inclusion the way to go and I'm just handling it incorrectly?

Instead of reading all text and setting it with setText() you must use the setSource() method and pass it to the QUrl using the QUr::fromLocalFile() method.
main.cpp
#include <QtWidgets>
class Widget: public QWidget
{
Q_OBJECT
public:
Widget(QWidget *parent=nullptr):
QWidget(parent),
m_text_browser(new QTextBrowser)
{
m_lineedit = new QLineEdit;
auto button = new QPushButton("Load");
auto lay = new QVBoxLayout{this};
auto hlay = new QHBoxLayout;
lay->addLayout(hlay);
hlay->addWidget(m_lineedit);
hlay->addWidget(button);
lay->addWidget(m_text_browser);
connect(button, &QPushButton::clicked, this, &Widget::on_clicked);
}
private slots:
void on_clicked(){
QString fileName = QFileDialog::getOpenFileName(this,
tr("Open Image"),
QDir::homePath(),
tr("HTML Files (*.html)"));
m_lineedit->setText(fileName);
m_text_browser->setSource(QUrl::fromLocalFile(fileName));
}
private:
QTextBrowser *m_text_browser;
QLineEdit *m_lineedit;
};
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Widget w;
w.showMaximized();
return a.exec();
}
#include "main.moc"

Related

How to pass a JSON object inside a QTextEdit

I have a small GUI that I use to load/save json configuration files, the most important parameters are in the gui below:
![conf]
The problem I have been trying to solve is that I am not able to create an object inside a QTextEdit and am not sure why despite I am following official documentation on how to do that.
Below a snippet of code both for the load and save button.
Also for the sake of brevity I only kept how I did the spinbox and, of course, the textedit:
void SettingsForm::on_loadBtn_clicked()
{
// Opening file dialog....
if(listDocksConfig.isEmpty())
{
QMessageBox::information(this, tr("Message"), tr("Please Open Configuration"));
}
else
{
QJsonDocument doc;
QJsonObject obj;
QByteArray data_json;
QFile input(listDocksConfig);
if(input.open(QIODevice::ReadOnly | QIODevice::Text))
{
data_json = input.readAll();
doc = doc.fromJson(data_json);
obj = doc.object();
const double xposValue = obj["X Pos"].toDouble();
QTextEdit textEdit = QTextEdit::setText(obj["comments"]); // <- Error Here
ui->doubleSpinBox_XPos->setValue(xposValue);
ui->textEdit->setText(textEdit); // <- Error Here
}
else
{
// do something
}
}
}
void SettingsForm::on_saveBtn_clicked()
{
// saving configuration with file dialog....
if(listDocksConfig.isEmpty())
{
// do something...
}
else
{
const double xposValue = ui->doubleSpinBox_XPos->value();
QTextEdit textEdit = ui->textEdit->setPlainText(); // <- Error Here
QJsonDocument doc;
QJsonObject obj;
obj["X Pos"] = xposValue;
obj["comments"] = textEdit.toString(); // <- Error Here
doc.setObject(obj);
QByteArray data_json = doc.toJson();
QFile output(listDocksConfig);
}
}
What I have done so far:
I consulted the official documentation on how to solve this problem, but could not figure out why that was not working. I also went ahead and try to use an alternative such as setText but still no luck.
I came across this source which I used as guidance for my example and solved almost all problems but the QTextEdit one.
This additional post was useful but still couldn't solve the problem.
Thanks for pointing to the right direction for solving this problem.
this line is wrong!!
QTextEdit textEdit = ui->textEdit->setPlainText();
setPlainText() needs const QString &text as parameter
you cant do that, read the official doc here
the method is void, ie. it returns nothing so you can not use void to init a QTextEdit object
update:
you already have a textEdit in the layout, so no reason to redefine one...
you can do:
ui->textEdit->setPlainText(obj["comments"].toString());

QWebEngineView - loading of > 2mb content

So, using PyQt5's QWebEngineView and the .setHTML and .setContent methods have a 2 MB size limitation. When googling for solutions around this, I found two methods:
Use SimpleHTTPServer to serve the file. This however gets nuked by a firewall employed in the company.
Use File Urls and point to local files. This however is a rather bad solution, as the HTML contains confidential data and I can't leave it on the harddrive, under any circumstance.
The best solution I currently see is to use file urls, and get rid of the file on program exit/when loadCompleted reports it is done, whichever comes first.
This is however not a great solution and I wanted to ask if there is a solution I'm overlooking that would be better?
Why don't you load/link most of the content through a custom url scheme handler?
webEngineView->page()->profile()->installUrlSchemeHandler("app", new UrlSchemeHandler(e));
class UrlSchemeHandler : public QWebEngineUrlSchemeHandler
{ Q_OBJECT
public:
void requestStarted(QWebEngineUrlRequestJob *request) {
QUrl url = request->requestUrl();
QString filePath = url.path().mid(1);
// get the data for this url
QByteArray data = ..
//
if (!data.isEmpty())
{
QMimeDatabase db;
QString contentType = db.mimeTypeForFileNameAndData(filePath,data).name();
QBuffer *buffer = new QBuffer();
buffer->open(QIODevice::WriteOnly);
buffer->write(data);
buffer->close();
connect(request, SIGNAL(destroyed()), buffer, SLOT(deleteLater()));
request->reply(contentType.toUtf8(), buffer);
} else {
request->fail(QWebEngineUrlRequestJob::UrlNotFound);
}
}
};
you can then load a website by webEngineView->load(new QUrl("app://start.html"));
All relative pathes from inside will also be forwarded to your UrlSchemeHandler..
And rember to add the respective includes
#include <QWebEngineUrlRequestJob>
#include <QWebEngineUrlSchemeHandler>
#include <QBuffer>
One way you can go around this is to use requests and QWebEnginePage's method runJavaScript:
web_engine = QWebEngineView()
web_page = web_engine.page()
web_page.setHtml('')
url = 'https://youtube.com'
page_content = requests.get(url).text
# document.write writes a string of text to a document stream
# https://developer.mozilla.org/en-US/docs/Web/API/Document/write
# And backtick symbol(``) is for multiline strings
web_page.runJavaScript('document.write(`{}`);'.format(page_content))

how to parse an html source code

I'm trying to parse a html source code. this is the webpage address I'm trying to parse. I have wrote the code below but it doesn't work at the last step that I wanna pull-out content of meta:
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QNetworkAccessManager manager;
QNetworkReply *reply = manager.get(QNetworkRequest(QUrl("https://www.instagram.com/p/BTwnRykl6EM/")));
QEventLoop event;
QObject::connect(reply, SIGNAL(finished()), &event, SLOT(quit()));
event.exec();
QString me = reply->readAll();
QString x;
//-------------------------------------------------------------------------------------------------------
//qDebug()<<me;
//-------------------------------------------------------------------------------------------------------
QXmlStreamReader reader(me);
if(reader.readNextStartElement()){
if(reader.name()=="html"){
while (reader.readNextStartElement()) {
if(reader.name()=="head"){
while (reader.readNextStartElement()) {
if(reader.name()=="meta" && reader.attributes().hasAttribute("property") && reader.attributes().value("property").toString()=="og:image")
x = reader.attributes().value("content").toString();
else{
qDebug()<<"why?";
reader.skipCurrentElement();
}
}
}
else
reader.skipCurrentElement();
}
}
else
reader.skipCurrentElement();
}
qDebug()<<x;
return 0;
}
and this part doesn't work:
if(reader.name()=="meta" && reader.attributes().hasAttribute("property") && reader.attributes().value("property").toString()=="og:image")
x = reader.attributes().value("content").toString();
else{
qDebug()<<"why?";
reader.skipCurrentElement();
}
and prints
why?
what is wrong with my code?
HTML is not a valid XML, so you can't use XML parsers. Options for HTML you can find on this wiki page.
Shortly, you can use Qt's Scribe framework or QtWebKit for automatic parsing and rendering HTML, or external libraries for manual parsing:
libxml2 (Win, Mac, Linux)
htmlcxx (Win, Linux)
libhtml (Linux)
libxml2 and libhtml are C libraries, htmlcxx is C++ library, that allows build dom-tree and iterate through it.

windows 8 app FileOpenPicker np file info

I'm trying to get some file information about a file the user select with the FileOpenPicker, but all the information like the path and name are empty. When I try to view the object in a breakpoint I got the following message:
file = 0x03489cd4 <Information not available, no symbols loaded for shell32.dll>
I use the following code for calling the FileOpenPicker and handeling the file
#include "pch.h"
#include "LocalFilePicker.h"
using namespace concurrency;
using namespace Platform;
using namespace Windows::Storage;
using namespace Windows::Storage::Pickers;
const int LocalFilePicker::AUDIO = 0;
const int LocalFilePicker::VIDEO = 1;
const int LocalFilePicker::IMAGES = 2;
LocalFilePicker::LocalFilePicker()
{
_init();
}
void LocalFilePicker::_init()
{
_openPicker = ref new FileOpenPicker();
_openPicker->ViewMode = PickerViewMode::Thumbnail;
}
void LocalFilePicker::askFile(int categorie)
{
switch (categorie)
{
case 0:
break;
case 1:
_openPicker->SuggestedStartLocation = PickerLocationId::VideosLibrary;
_openPicker->FileTypeFilter->Append(".mp4");
break;
case 2:
break;
default:
break;
}
create_task(_openPicker->PickSingleFileAsync()).then([this](StorageFile^ file)
{
if (file)
{
int n = 0;
wchar_t buf[1024];
_snwprintf_s(buf, 1024, _TRUNCATE, L"Test: '%s'\n", file->Path);
OutputDebugString(buf);
}
else
{
OutputDebugString(L"canceled");
}
});
}
Can anybody see whats wrong with the code or some problems with settings for the app why it isn't work as expected.
First an explanation why you are having trouble debugging, this is going to happen a lot more when you write WinRT programs. First, do make sure that you have the correct debugging engine enabled. Tools + Options, Debugging, General. Ensure that the "Use Managed Compatibility Mode" is turned off.
You can now inspect the "file" option, it should resemble this:
Hard to interpret of course. What you are looking at is a proxy. It is a COM term, a wrapper for COM objects that are not thread-safe or live in another process or machine. The proxy implementation lives in shell32.dll, thus the confuzzling diagnostic message. You can't see the actual object at all, accessing its properties requires calling proxy methods. Something that the debugger is not capable of doing, a proxy marshals the call from one thread to another, that other thread is frozen while the debugger break is active.
That makes you pretty blind, in tough cases you may want to write a littler helper code to store the property in a local variable. Like:
auto path = file->Path;
No trouble inspecting or watching that one. You should now have confidence that there's nothing wrong with file and you get a perfectly good path. Note how writing const wchar_t* path = file->Path; gets you a loud complaint from the compiler.
Which helps you find the bug, you can't pass a Platform::String to a printf() style function. Just like you can't with, say, std::wstring. You need to use an accessor function to convert it. Fix:
_snwprintf_s(buf, 1024, _TRUNCATE,
L"Test: '%s'\n",
file->Path->Data());

Render HTML on headless server to produce screenshots

I would like to create screenshots of web pages from a given URL. While it's possible to use tools like Selenium RC, that requires a graphical environment. I am running a headless Gentoo server.
This will be part of a tool chain that works like:
Fetch URL
Render HTML
Export render as image file
Store image file
You can run an application with framebuffer X-Server like xvfb - one simple approach is a Qt based app to render the page in a webkit widget and save as an image. Here's a blog post outlining how this can be done with Python.
Here's a quick command line tool I've used with Qt. It's a while since I used it but it should still work!
#include <QtCore/QCoreApplication>
#include <QtGui>
#include <QtWebKit>
#include <QTextStream>
#include <QSize>
QWebView *view;
QString outfile;
void QWebView::loadFinished(bool ok)
{
QTextStream out(stdout);
if (!ok) {
out << "Page loading failed\n";
return;
}
view->page()->setViewportSize(view->page()->currentFrame()->contentsSize());
QImage *img = new QImage(view->page()->viewportSize(), QImage::Format_ARGB32);
QPainter *paint = new QPainter(img);
view->page()->currentFrame()->render(paint);
paint->end();
if(!img->save(outfile, "png"))
out << "Save failure\n";
QApplication::quit();
return;
}
int main(int argc, char *argv[])
{
QTextStream out(stdout);
if(argc < 3) {
out << "USAGE: " << argv[0] << " <url> <outfile>\n";
return -1;
}
outfile = argv[2];
QApplication app(argc, argv);
view = new QWebView();
view->load(QUrl(argv[1]));
return app.exec();
}