QWebEngineView Class

The QWebEngineView class provides a widget that is used to view and edit web documents. More...

Header:	#include <QWebEngineView>
qmake:	QT += webenginewidgets
Since:	Qt 5.4
Inherits:	QWidget

This class was introduced in Qt 5.4.

• List of all members, including inherited members

Properties

hasSelection : const bool icon : const QIcon iconUrl : const QUrl selectedText : const QString

title : const QString url : QUrl zoomFactor : qreal

Public Functions

	QWebEngineView(QWidget *parent = Q_NULLPTR)
virtual	~QWebEngineView()
void	findText(const QString &subString, QWebEnginePage::FindFlags options = ..., const QWebEngineCallback<bool> &resultCallback = ...)
bool	hasSelection() const
QWebEngineHistory *	history() const
QIcon	icon() const
QUrl	iconUrl() const
void	load(const QUrl &url)
void	load(const QWebEngineHttpRequest &request)
QWebEnginePage *	page() const
QAction *	pageAction(QWebEnginePage::WebAction action) const
QString	selectedText() const
void	setContent(const QByteArray &data, const QString &mimeType = QString(), const QUrl &baseUrl = QUrl())
void	setHtml(const QString &html, const QUrl &baseUrl = QUrl())
void	setPage(QWebEnginePage *page)
void	setUrl(const QUrl &url)
void	setZoomFactor(qreal factor)
QWebEngineSettings *	settings() const
QString	title() const
void	triggerPageAction(QWebEnginePage::WebAction action, bool checked = false)
QUrl	url() const
qreal	zoomFactor() const

Reimplemented Public Functions

virtual QSize

sizeHint() const override

Public Slots

void	back()
void	forward()
void	reload()
void	stop()

Signals

void	iconChanged(const QIcon &icon)
void	iconUrlChanged(const QUrl &url)
void	loadFinished(bool ok)
void	loadProgress(int progress)
void	loadStarted()
void	renderProcessTerminated(QWebEnginePage::RenderProcessTerminationStatus terminationStatus, int exitCode)
void	selectionChanged()
void	titleChanged(const QString &title)
void	urlChanged(const QUrl &url)

Protected Functions

virtual QWebEngineView *

createWindow(QWebEnginePage::WebWindowType type)

Reimplemented Protected Functions

virtual void	closeEvent(QCloseEvent *event) override
virtual void	contextMenuEvent(QContextMenuEvent *event) override
virtual void	dragEnterEvent(QDragEnterEvent *e) override
virtual void	dragLeaveEvent(QDragLeaveEvent *e) override
virtual void	dragMoveEvent(QDragMoveEvent *e) override
virtual void	dropEvent(QDropEvent *e) override
virtual bool	event(QEvent *ev) override
virtual void	hideEvent(QHideEvent *event) override
virtual void	showEvent(QShowEvent *event) override

Detailed Description

A web view is the main widget component of the Qt WebEngine web browsing module. It can be used in various applications to display web content live from the Internet.

A web site can be loaded to a web view with the load() function. The GET method is always used to load URLs.

Like all Qt widgets, the show() function must be invoked in order to display the web view. The snippet below illustrates this:

    QWebEngineView *view = new QWebEngineView(parent);
    view->load(QUrl("http://qt-project.org/"));
    view->show();

Alternatively, setUrl() can be used to load a web site. If you have the HTML content readily available, you can use setHtml() instead.

The loadStarted() signal is emitted when the view begins loading and the loadProgress() signal is emitted whenever an element of the web view completes loading, such as an embedded image or a script. The loadFinished() signal is emitted when the view has been loaded completely. Its argument, either true or false, indicates whether loading was successful or failed.

The page() function returns a pointer to a web page object. A QWebEngineView contains a QWebEnginePage, which in turn allows access to the QWebEngineHistory in the page's context.

The title of an HTML document can be accessed with the title() property. Additionally, a web site may specify an icon, which can be accessed using the icon() or its URL using the iconUrl() property. If the title or the icon changes, the corresponding titleChanged(), iconChanged() and iconUrlChanged() signals will be emitted. The zoomFactor() property enables zooming the contents of the web page by a scale factor.

The widget features a context menu that is tailored to the element at hand, and includes actions useful in a browser. For a custom context menu, or for embedding actions in a menu or toolbar, the individual actions are available via pageAction(). The web view maintains the state of the returned actions, but allows modification of action properties such as text or icon. The action semantics can also be triggered directly through triggerPageAction().

If you want to provide support for web sites that allow the user to open new windows, such as pop-up windows, you can subclass QWebEngineView and reimplement the createWindow() function.

See also WebEngine Widgets Simple Browser Example, WebEngine Content Manipulation Example, and WebEngine Markdown Editor Example.

Member Function Documentation

QWebEngineView::QWebEngineView(QWidget *parent = Q_NULLPTR)

Constructs an empty web view with the parent parent.

See also load().

[slot] void QWebEngineView::back()

Convenience slot that loads the previous document in the list of documents built by navigating links. Does nothing if there is no previous document.

It is equivalent to:

    view->page()->triggerAction(QWebEnginePage::Back);

See also forward() and pageAction().

[slot] void QWebEngineView::forward()

Convenience slot that loads the next document in the list of documents built by navigating links. Does nothing if there is no next document.

It is equivalent to:

    view->page()->triggerAction(QWebEnginePage::Forward);

See also back() and pageAction().

[signal] void QWebEngineView::iconChanged(const QIcon &icon)

This signal is emitted when the icon ("favicon") associated with the view is changed. The new icon is specified by icon.

This function was introduced in Qt 5.7.

Note: Notifier signal for property icon.

See also icon(), iconUrl(), and iconUrlChanged().

[signal] void QWebEngineView::iconUrlChanged(const QUrl &url)

This signal is emitted when the URL of the icon ("favicon") associated with the view is changed. The new URL is specified by url.

Note: Notifier signal for property iconUrl.

See also iconUrl(), icon(), and iconChanged().

[signal] void QWebEngineView::loadFinished(bool ok)

This signal is emitted when a load of the page has finished. ok will indicate whether the load was successful or an error occurred.

See also loadStarted().

[signal] void QWebEngineView::loadProgress(int progress)

This signal is emitted every time an element in the web view completes loading, such as an embedded image or a script. Therefore, it tracks the collective progress of loading the web view.

The current value is provided by progress and scales from 0 to 100, which is the default range of QProgressBar.

See also loadStarted() and loadFinished().

[signal] void QWebEngineView::loadStarted()

This signal is emitted when a new load of the page is started.

See also loadProgress() and loadFinished().

[slot] void QWebEngineView::reload()

Reloads the current document.

See also stop(), pageAction(), and loadStarted().

[signal] void QWebEngineView::renderProcessTerminated(QWebEnginePage::RenderProcessTerminationStatus terminationStatus, int exitCode)

This signal is emitted when the render process is terminated with a non-zero exit status. terminationStatus is the termination status of the process and exitCode is the status code with which the process terminated.

This function was introduced in Qt 5.6.

[signal] void QWebEngineView::selectionChanged()

This signal is emitted whenever the selection changes.

Note: When using the mouse to select text by left-clicking and dragging, the signal will be emitted for each new character selected, and not upon releasing the left mouse button.

See also selectedText().

[slot] void QWebEngineView::stop()

Convenience slot that stops loading the document.

It is equivalent to:

    view->page()->triggerAction(QWebEnginePage::Stop);

See also reload(), pageAction(), and loadFinished().

[signal] void QWebEngineView::titleChanged(const QString &title)

This signal is emitted whenever the title of the view changes.

See also title().

[signal] void QWebEngineView::urlChanged(const QUrl &url)

This signal is emitted when the url of the view changes.

See also url() and load().

[virtual] QWebEngineView::~QWebEngineView()

Destroys the web view.

[override virtual protected] void QWebEngineView::closeEvent(QCloseEvent *event)

Reimplements: QWidget::closeEvent(QCloseEvent *event).

[override virtual protected] void QWebEngineView::contextMenuEvent(QContextMenuEvent *event)

Reimplements: QWidget::contextMenuEvent(QContextMenuEvent *event).

[virtual protected] QWebEngineView *QWebEngineView::createWindow(QWebEnginePage::WebWindowType type)

This function is called from the createWindow() method of the associated QWebEnginePage each time the page wants to create a new window of the given type. For example, when a JavaScript request to open a document in a new window is issued.

Note: If the createWindow() method of the associated page is reimplemented, this method is not called, unless explicitly done so in the reimplementation.

See also QWebEnginePage::createWindow().

[override virtual protected] void QWebEngineView::dragEnterEvent(QDragEnterEvent *e)

Reimplements: QWidget::dragEnterEvent(QDragEnterEvent *event).

[override virtual protected] void QWebEngineView::dragLeaveEvent(QDragLeaveEvent *e)

Reimplements: QWidget::dragLeaveEvent(QDragLeaveEvent *event).

[override virtual protected] void QWebEngineView::dragMoveEvent(QDragMoveEvent *e)

Reimplements: QWidget::dragMoveEvent(QDragMoveEvent *event).

[override virtual protected] void QWebEngineView::dropEvent(QDropEvent *e)

Reimplements: QWidget::dropEvent(QDropEvent *event).

[override virtual protected] bool QWebEngineView::event(QEvent *ev)

Reimplements: QWidget::event(QEvent *event).

void QWebEngineView::findText(const QString &subString, QWebEnginePage::FindFlags options = ..., const QWebEngineCallback<bool> &resultCallback = ...)

Finds the specified string, subString, in the page, using the given options.

To clear the selection, just pass an empty string.

resultCallback must take a boolean parameter. It will be called with a value of true if subString was found; otherwise the callback value will be false.

Warning: We guarantee that the callback (resultCallback) is always called, but it might be done during page destruction. When QWebEnginePage is deleted, the callback is triggered with an invalid value and it is not safe to use the corresponding QWebEnginePage or QWebEngineView instance inside it.

See also selectedText() and selectionChanged().

[override virtual protected] void QWebEngineView::hideEvent(QHideEvent *event)

Reimplements: QWidget::hideEvent(QHideEvent *event).

QWebEngineHistory *QWebEngineView::history() const

Returns a pointer to the view's history of navigated web pages.

It is equivalent to:

    view->page()->history();

void QWebEngineView::load(const QUrl &url)

Loads the specified url and displays it.

Note: The view remains the same until enough data has arrived to display the new URL.

See also load(), setUrl(), url(), urlChanged(), and QUrl::fromUserInput().

void QWebEngineView::load(const QWebEngineHttpRequest &request)

Issues the specified request and loads the response.

This function was introduced in Qt 5.9.

See also load(), setUrl(), url(), urlChanged(), and QUrl::fromUserInput().

QWebEnginePage *QWebEngineView::page() const

Returns a pointer to the underlying web page.

See also setPage().

QAction *QWebEngineView::pageAction(QWebEnginePage::WebAction action) const

Returns a pointer to a QAction that encapsulates the specified web action action.

void QWebEngineView::setContent(const QByteArray &data, const QString &mimeType = QString(), const QUrl &baseUrl = QUrl())

Sets the content of the web view to data. If the mimeType argument is empty, it is assumed that the content is text/plain,charset=US-ASCII.

External objects referenced in the content are located relative to baseUrl. For external objects to be loaded, baseUrl cannot be empty.

The data is loaded immediately; external objects are loaded asynchronously.

See also load(), setHtml(), and QWebEnginePage::toHtml().

void QWebEngineView::setHtml(const QString &html, const QUrl &baseUrl = QUrl())

Sets the content of the web view to the specified html content.

External objects, such as stylesheets or images referenced in the HTML document, are located relative to baseUrl. For external objects to be loaded, baseUrl cannot be empty. For example, if html is retrieved from http://www.example.com/documents/overview.html, which is the base URL, then an image referenced with the relative URL, diagram.png, should be at http://www.example.com/documents/diagram.png.

The HTML document is loaded immediately, whereas external objects are loaded asynchronously.

When using this method, Qt WebEngine assumes that external resources, such as JavaScript programs or style sheets, are encoded in UTF-8 unless otherwise specified. For example, the encoding of an external script can be specified through the charset attribute of the HTML script tag. Alternatively, the encoding can be specified by the web server.

This is a convenience function equivalent to setContent(html, "text/html;charset=UTF-8", baseUrl).

Warning: This function works only for HTML. For other MIME types (such as XHTML or SVG), setContent() should be used instead.

Note: Content larger than 2 MB cannot be displayed, because setHtml() converts the provided HTML to percent-encoding and places data: in front of it to create the URL that it navigates to. Thereby, the provided code becomes a URL that exceeds the 2 MB limit set by Chromium. If the content is too large, the loadFinished() signal is triggered with success=false.

See also load(), setContent(), QWebEnginePage::toHtml(), and QWebEnginePage::setContent().

void QWebEngineView::setPage(QWebEnginePage *page)

Makes page the new web page of the web view.

The parent QObject of the provided page remains the owner of the object. If the current page is a child of the web view, it will be deleted.

See also page().

QWebEngineSettings *QWebEngineView::settings() const

Returns a pointer to the view or page specific settings object.

It is equivalent to:

    view->page()->settings();

See also QWebEngineSettings::defaultSettings().

[override virtual protected] void QWebEngineView::showEvent(QShowEvent *event)

Reimplements: QWidget::showEvent(QShowEvent *event).

[override virtual] QSize QWebEngineView::sizeHint() const

Reimplements an access function for property: QWidget::sizeHint.

void QWebEngineView::triggerPageAction(QWebEnginePage::WebAction action, bool checked = false)

Triggers the specified action. If it is a checkable action, the specified checked state is assumed.

The following example triggers the copy action and therefore copies any selected text to the clipboard.

    view->triggerPageAction(QWebEnginePage::Copy);

See also pageAction().