WebEngine Widgets PrintMe Example

Demonstrates how to print web pages using Qt WebEngine Widgets.

PrintMe demonstrates how to use the QWebEnginePage and QPrintDialog classes to print a web page. Further, it shows how to implement print preview by using the QPrintPreviewDialog class. For completeness, it also illustrates how to trigger a printing request within JavaScript.

Running the Example

To run the example from Qt Creator , open the Welcome mode and select the example from Examples. For more information, visit Building and Running an Example.

Simple HTML Page

In this example, we create an internal HTML page that is added as a resource collection file (.qrc). The page shows only a small HTML message box that explains how to trigger printing by using keyboard shortcuts or clicking a button. The button has the JavaScript onclick event attribute that calls the JavaScript window.print() function.

Main Function

In the main function, we first instantiate a QWebEngineView and set the URL to our internal HTML page. Next, we create a PrintHandler instance and pass the requested page. For convenience, we also create keyboard shortcuts that can be used to call a print dialog or print preview dialog.

Print Handler

In the PrintHandler class, we first implement printPreview(), where we instantiate QPrintPreviewDialog . We need the paintRequested handle to generate a set of preview pages.

Now we can implement the PrintHandler::printDocument() slot, which is called in response to the paintRequested signal. To do actual painting on a printer, we call the print() function. Because this call is asynchronous, we need to use a local event loop. We begin the local event loop by calling exec() .

To get notified about the result of printing job, we implement PrintHandler::printFinished() slot as handler of printFinished() signal. We check for success and report any errors that occurred.

The last function we implement, PrintHandler::print(), is trivial, because it simply opens QPrintDialog and calls the previously implemented PrintHandler::printDocument().

Example project @ code.qt.io