diff options
| author | Michal Klocek <michal.klocek@qt.io> | 2018-07-06 15:11:49 +0200 |
|---|---|---|
| committer | Michal Klocek <michal.klocek@qt.io> | 2019-04-15 07:22:07 +0000 |
| commit | 4f5380f413a8a5e89ee57f301a9d6010eac92ad4 (patch) | |
| tree | ed5ce6541939bf6f863eda1e4ddae013435afed2 /examples/webenginewidgets/printme/doc/src/printme.qdoc | |
| parent | 1b7c7d853978d5a2ebc4ed06f4879c35bd68aa4f (diff) | |
Add PrintMe example
This example shows how to do simple printing with
print preview.
Task-number: QTBUG-53745
Change-Id: I4b1adbb9847b72928a988b5687fb13c84bb987cd
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
Diffstat (limited to 'examples/webenginewidgets/printme/doc/src/printme.qdoc')
| -rw-r--r-- | examples/webenginewidgets/printme/doc/src/printme.qdoc | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/examples/webenginewidgets/printme/doc/src/printme.qdoc b/examples/webenginewidgets/printme/doc/src/printme.qdoc new file mode 100644 index 000000000..d05d5147b --- /dev/null +++ b/examples/webenginewidgets/printme/doc/src/printme.qdoc @@ -0,0 +1,98 @@ +/**************************************************************************** +** +** Copyright (C) 2019 The Qt Company Ltd. +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:FDL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU Free Documentation License Usage +** Alternatively, this file may be used under the terms of the GNU Free +** Documentation License version 1.3 as published by the Free Software +** Foundation and appearing in the file included in the packaging of +** this file. Please review the following information to ensure +** the GNU Free Documentation License version 1.3 requirements +** will be met: https://www.gnu.org/licenses/fdl-1.3.html. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \example webenginewidgets/printme + \title WebEngine Widgets PrintMe Example + \ingroup webengine-widgetexamples + \brief Demonstrates how to print web pages using Qt WebEngine Widgets. + + \image printme-example.png + + \e PrintMe demonstrates how to use the \l{QWebEnginePage} and + \l{QPrintDialog} classes to print a web page. Further, it shows how + to implement print preview by using the \l{QPrintPreviewDialog} class. + For completeness, it also illustrates how to trigger a printing request + within JavaScript. + + \include examples-run.qdocinc + + \section1 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 \c{onclick} event attribute that calls + the JavaScript \c{window.print()} function. + + \quotefromfile webenginewidgets/printme/data/index.html + \skipto <html + \printuntil html> + + \section1 Main Function + + In the \c main function, we first instantiate a QWebEngineView and set the + URL to our internal HTML page. Next, we create a \c 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. + + \quotefromfile webenginewidgets/printme/main.cpp + \skipto QWebEngineView view + \printto return + + \section1 Print Handler + + In the \c{PrintHandler} function, we first implement \c{printPreview()}, + where we instantiate \l{QPrinter} together with \l{QPrintPreviewDialog}. + We need the \l{QPrintPreviewDialog::paintRequested} handle to generate a + set of preview pages. + + \quotefromfile webenginewidgets/printme/printhandler.cpp + \skipto PrintHandler::printPreview( + \printuntil /^\}/ + + Now we can implement the \c{PrintHandler::printDocument()} slot, which is + called in response to the \l{QPrintPreviewDialog::paintRequested} signal. + + \quotefromfile webenginewidgets/printme/printhandler.cpp + \skipto PrintHandler::printDocument( + \printuntil /^\}/ + + To do actual painting on a printer, we call the \l{QWebEnginePage::print()} + function. Because this call blocks the main event loop, we need to create + a local one. We begin the local event loop by calling + \l{QEventLoop::exec()}. When the local event loop terminates, + we check for \c{result} and report any errors that occurred. + + The last function we implement, \c{PrintHandler::print()}, is trivial, + because it simply opens \l{QPrintDialog} and calls the previously + implemented \c{PrintHandler::printDocument()}. + + \quotefromfile webenginewidgets/printme/printhandler.cpp + \skipto PrintHandler::print( + \printuntil /^\}/ +*/ |