Proxy Data Sources

The first thing you need to do to use a proxy in your browser is to make the necessary settings. In Google Chrome browser, go to "Network" and then find and click on "Change proxy settings". In the "Internet properties" window that opens, go to "Connection" and click on the "Network settings" button at the bottom. When a new window opens, check the "Use proxy server for local connections" box and the "Do not use proxy server for local addresses" box. Enter the proxy port and IP address in the corresponding fields, close the window and click "OK".

Qt primarily focuses on providing tools and libraries for GUI development, networking, and other application-level features. While it includes facilities for working with XML through classes like QXmlStreamReader and QXmlStreamWriter, these are more geared toward parsing XML rather than HTML.

For HTML parsing, especially when using XPath expressions, you might need to consider additional libraries or tools. One common choice is to use a third-party library like Gumbo or htmlcxx. These libraries are not part of the Qt framework, but they can be used alongside Qt to handle HTML parsing.

Here's a basic example using htmlcxx for HTML parsing:

#include 
#include 
#include 

int main(int argc, char *argv[]) {
    QCoreApplication a(argc, argv);

    std::string htmlData = "
Hello, world!
";

    htmlcxx::HTML::ParserDom parser;
    tree dom = parser.parseTree(htmlData);

    // Example XPath query
    std::string xpathExpression = "//p/span";
    std::vector::iterator> result;
    htmlcxx::XPath::NodeSet nodeSet;
    htmlcxx::XPath::Parser xpathParser;
    xpathParser.compile(xpathExpression.c_str(), &nodeSet);

    for (tree::iterator it = dom.begin(); it != dom.end(); ++it) {
        nodeSet.evaluate(*it);
        if (nodeSet.size() > 0) {
            result.push_back(it);
        }
    }

    // Output the result
    for (auto &it : result) {
        std::cout << "Match found: " << htmlcxx::HTML::toPlainText(it->begin(), it->end()) << std::endl;
    }

    return a.exec();
}

In this example, I've used htmlcxx for HTML parsing and XPath queries. Note that you need to include the htmlcxx library in your project.

To find the proxy server of your printer, follow these steps:

1. Check the printer manual: The manual may contain information about the proxy server or how to access the printer's settings.

2. Access the printer's settings: Connect your printer to your computer or network, and then access the printer's settings through the printer's control panel or the software you use to manage the printer.

3. Look for network settings: In the printer settings, search for a section related to network settings, network configuration, or network connection.

4. Find the proxy server information: In the network settings, look for information about the proxy server address, port, and authentication details (if applicable).

If you're unable to find the proxy server information in the printer settings, it's possible that your printer doesn't use a proxy server. In such cases, you can directly connect the printer to the internet using an Ethernet cable or through your Wi-Fi network.

In the browser settings, select "Open Browser Settings" and then, finding the "Advanced" button, go to the "System" section. Click on the button "Open proxy server settings for computer" and in the section "Manual proxy settings" move the slider to the position "On". Now enter in the appropriate fields the IP address, proxy, port and click "Save".

In the settings bar (home screen), select "Network Settings" and then click on Ethernet. Here you should select the "Advanced Settings" option, which contains the "Proxy Server Settings" item. To further configure the proxy, select "Configure Manually", type in the proxy hostname and specify the port. Do not forget to list the domains that the proxy server should not use. You should leave this field empty if it does not exist. If the configuration process is successful, you will see the "Settings saved" notification.