Qt 5.7 | Qt WebEngine | C++ Classes | QWebEngineProfile

Qt 5.7.1 Reference Documentation

# QWebEngineProfile Class

The QWebEngineProfile class provides a web engine profile shared by multiple pages. More...

Header: | #include <QWebEngineProfile>
qmake: | QT += webenginewidgets
Since: | Qt 5.5

- List of all members, including inherited members

## Public Types

enum | HttpCacheType { MemoryHttpCache, DiskHttpCache, NoCache }
enum | PersistentCookiesPolicy { NoPersistentCookies, AllowPersistentCookies, ForcePersistentCookies }

## Public Functions

| QWebEngineProfile(QObject *parent = Q_NULLPTR)
| QWebEngineProfile(const QString &storageName, QObject *parent = Q_NULLPTR)
QString | cachePath() const
void | clearAllVisitedLinks()
void | clearHttpCache()
void | clearVisitedLinks(const QList<QUrl> &urls)
QWebEngineCookieStore * | cookieStore()
QString | httpAcceptLanguage() const
int | httpCacheMaximumSize() const
HttpCacheType | httpCacheType() const
QString | httpUserAgent() const
void | installUrlSchemeHandler(const QByteArray &scheme, QWebEngineUrlSchemeHandler *handler)
bool | isOffTheRecord() const
PersistentCookiesPolicy | persistentCookiesPolicy() const
QString | persistentStoragePath() const
void | removeAllUrlSchemeHandlers()
void | removeUrlScheme(const QByteArray &scheme)
void | removeUrlSchemeHandler(QWebEngineUrlSchemeHandler *handler)
QWebEngineScriptCollection * | scripts() const
void | setCachePath(const QString &path)
void | setHttpAcceptLanguage(const QString &httpAcceptLanguage)
void | setHttpCacheMaximumSize(int maxSize)
void | setHttpCacheType(QWebEngineProfile::HttpCacheType httpCacheType)
void | setHttpUserAgent(const QString &userAgent)
void | setPersistentCookiesPolicy(QWebEngineProfile::PersistentCookiesPolicy newPersistentCookiesPolicy)
void | setPersistentStoragePath(const QString &path)
void | setRequestInterceptor(QWebEngineUrlRequestInterceptor *interceptor)
QWebEngineSettings * | settings() const
QString | storageName() const
const QWebEngineUrlSchemeHandler * | urlSchemeHandler(const QByteArray &scheme) const
bool | visitedLinksContainsUrl(const QUrl &url) const

## Signals

void | downloadRequested(QWebEngineDownloadItem *download)

## Static Public Members

QWebEngineProfile * | defaultProfile()

## Detailed Description

The QWebEngineProfile class provides a web engine profile shared by multiple pages.

A web engine profile contains settings, scripts, persistent cookie policy, and the list of visited links shared by all web engine pages that belong to the profile.

All pages that belong to the profile share a common QWebEngineSettings instance, which can be accessed with the settings() method. Likewise, the scripts() method provides access to a common QWebEngineScriptCollection instance.

Information about visited links is stored together with persistent cookies and other persistent data in a storage returned by persistentStoragePath(). The cache can be cleared of links by clearVisitedLinks() or clearAllVisitedLinks(). PersistentCookiesPolicy describes whether session and persistent cookies are saved to and restored from memory or disk.

Profiles can be used to isolate pages from each other. A typical use case is a dedicated off-the-record profile for a private browsing mode. Using QWebEngineProfile() without defining a storage name constructs a new off-the-record profile that leaves no record on the local machine, and has no persistent data or cache. The isOffTheRecord() method can be used to check whether a profile is off-the-record.

The default profile can be accessed by defaultProfile(). It is a built-in profile that all web pages not specifically created with another profile belong to.

Implementing the QWebEngineUrlRequestInterceptor interface and registering the interceptor on a profile by setRequestInterceptor() enables intercepting, blocking, and modifying URL requests (QWebEngineUrlRequestInfo) before they reach the networking stack of Chromium.

A QWebEngineUrlSchemeHandler can be registered for a profile by installUrlSchemeHandler() to add support for custom URL schemes. Requests for the scheme are then issued to QWebEngineUrlSchemeHandler::requestStarted() as QWebEngineUrlRequestJob objects.

## Member Type Documentation

### enum QWebEngineProfile::HttpCacheType

This enum describes the HTTP cache type:

Constant | Value | Description
--- | --- | ---
`QWebEngineProfile::MemoryHttpCache` | `0` | Use an in-memory cache. This is the only setting possible if `off-the-record` is set or no cache path is available.
`QWebEngineProfile::DiskHttpCache` | `1` | Use a disk cache. This is the default.
`QWebEngineProfile::NoCache` | `2` | Disable both in-memory and disk caching. (Added in Qt 5.7)

### enum QWebEngineProfile::PersistentCookiesPolicy

This enum describes policy for cookie persistency:

Constant | Value | Description
--- | --- | ---
`QWebEngineProfile::NoPersistentCookies` | `0` | Both session and persistent cookies are stored in memory. This is the only setting possible if `off-the-record` is set or no persistent data path is available.
`QWebEngineProfile::AllowPersistentCookies` | `1` | Cookies marked persistent are saved to and restored from disk, whereas session cookies are only stored to disk for crash recovery. This is the default setting.
`QWebEngineProfile::ForcePersistentCookies` | `2` | Both session and persistent cookies are saved to and restored from disk.

## Member Function Documentation

### QWebEngineProfile::QWebEngineProfile(QObject *parent = Q_NULLPTR)

Constructs a new off-the-record profile with the parent parent.

An off-the-record profile leaves no record on the local machine, and has no persistent data or cache. Thus, the HTTP cache can only be in memory and the cookies can only be non-persistent. Trying to change these settings will have no effect.

See also isOffTheRecord().

### QWebEngineProfile::QWebEngineProfile(const QString &storageName, QObject *parent = Q_NULLPTR)

Constructs a new profile with the storage name storageName and parent parent.

The storage name must be unique.

A disk-based QWebEngineProfile should be destroyed on or before application exit, otherwise the cache and persistent data may not be fully flushed to disk.

See also storageName().

### QString QWebEngineProfile::cachePath() const

Returns the path used for caches.

By default, this is below QStandardPaths::writableLocation() in a storage name specific directory.

See also setCachePath(), storageName(), and QStandardPaths::writableLocation().

### void QWebEngineProfile::clearAllVisitedLinks()

Clears all links from the visited links database.

See also clearVisitedLinks().

### void QWebEngineProfile::clearHttpCache()

Removes the profile's cache entries.

This function was introduced in Qt 5.7.

### void QWebEngineProfile::clearVisitedLinks(const QList<QUrl> &urls)

Clears the links in urls from the visited links database.

See also clearAllVisitedLinks().

### QWebEngineCookieStore *QWebEngineProfile::cookieStore()

Returns the cookie store for this profile.

This function was introduced in Qt 5.6.

### `[static]` QWebEngineProfile *QWebEngineProfile::defaultProfile()

Returns the default profile.

The default profile uses the storage name "Default".

See also storageName().

### `[signal]` void QWebEngineProfile::downloadRequested(QWebEngineDownloadItem *download)

This signal is emitted whenever a download has been triggered. The download argument holds the state of the download. The download has to be explicitly accepted with QWebEngineDownloadItem::accept() or it will be cancelled by default. The download item is parented by the profile. If it is not accepted, it will be deleted immediately after the signal emission. This signal cannot be used with a queued connection.

This function was introduced in Qt 5.5.

See also QWebEngineDownloadItem.

### QString QWebEngineProfile::httpAcceptLanguage() const

Returns the value of the Accept-Language HTTP request-header field.

This function was introduced in Qt 5.6.

See also setHttpAcceptLanguage().

### int QWebEngineProfile::httpCacheMaximumSize() const

Returns the maximum size of the HTTP cache in bytes.

Will return `0` if the size is automatically controlled by QtWebEngine.

See also setHttpCacheMaximumSize() and httpCacheType().

### HttpCacheType QWebEngineProfile::httpCacheType() const

Returns the type of HTTP cache used.

If the profile is off-the-record, MemoryHttpCache is returned.

See also setHttpCacheType() and cachePath().

### QString QWebEngineProfile::httpUserAgent() const

Returns the user-agent string sent with HTTP to identify the browser.

See also setHttpUserAgent().

### void QWebEngineProfile::installUrlSchemeHandler(const QByteArray &scheme, QWebEngineUrlSchemeHandler *handler)

Registers a handler handler for custom URL scheme scheme in the profile.

This function was introduced in Qt 5.6.

### bool QWebEngineProfile::isOffTheRecord() const

Returns `true` if this is an off-the-record profile that leaves no record on the computer.

This will force cookies and HTTP cache to be in memory, but also force all other normally persistent data to be stored in memory.

### PersistentCookiesPolicy QWebEngineProfile::persistentCookiesPolicy() const

Returns the current policy for persistent cookies.

If the profile is off-the-record, NoPersistentCookies is returned.

See also setPersistentCookiesPolicy().

### QString QWebEngineProfile::persistentStoragePath() const

Returns the path used to store persistent data for the browser and web content.

Persistent data includes persistent cookies, HTML5 local storage, and visited links.

By default, this is below QStandardPaths::writableLocation() in a storage name specific directory.

See also setPersistentStoragePath(), storageName(), and QStandardPaths::writableLocation().

### void QWebEngineProfile::removeAllUrlSchemeHandlers()

Removes all custom URL scheme handlers installed in the profile.

This function was introduced in Qt 5.6.

### void QWebEngineProfile::removeUrlScheme(const QByteArray &scheme)

Removes the custom URL scheme scheme from the profile.

This function was introduced in Qt 5.6.

See also removeUrlSchemeHandler().

### void QWebEngineProfile::removeUrlSchemeHandler(QWebEngineUrlSchemeHandler *handler)

Removes the custom URL scheme handler handler from the profile.

This function was introduced in Qt 5.6.

See also removeUrlScheme().

### QWebEngineScriptCollection *QWebEngineProfile::scripts() const

Returns the collection of scripts that are injected into all pages that share this profile.

See also QWebEngineScriptCollection, QWebEngineScript, and QWebEnginePage::scripts().

### void QWebEngineProfile::setCachePath(const QString &path)

Overrides the default path used for disk caches, setting it to path.

If set to the null string, the default path is restored.

See also cachePath().

### void QWebEngineProfile::setHttpAcceptLanguage(const QString &httpAcceptLanguage)

Sets the value of the Accept-Language HTTP request-header field to httpAcceptLanguage.

This function was introduced in Qt 5.6.

See also httpAcceptLanguage().

### void QWebEngineProfile::setHttpCacheMaximumSize(int maxSize)

Sets the maximum size of the HTTP cache to maxSize bytes.

Setting it to `0` means the size will be controlled automatically by QtWebEngine.

See also httpCacheMaximumSize() and setHttpCacheType().

### void QWebEngineProfile::setHttpCacheType(QWebEngineProfile::HttpCacheType httpCacheType)

Sets the HTTP cache type to httpCacheType.

See also httpCacheType() and setCachePath().

### void QWebEngineProfile::setHttpUserAgent(const QString &userAgent)

Overrides the default user-agent string, setting it to userAgent.

See also httpUserAgent().

### void QWebEngineProfile::setPersistentCookiesPolicy(QWebEngineProfile::PersistentCookiesPolicy newPersistentCookiesPolicy)

Sets the policy for persistent cookies to newPersistentCookiesPolicy.

See also persistentCookiesPolicy().

### void QWebEngineProfile::setPersistentStoragePath(const QString &path)

Overrides the default path used to store persistent web engine data.

If path is set to the null string, the default path is restored.

See also persistentStoragePath().

### void QWebEngineProfile::setRequestInterceptor(QWebEngineUrlRequestInterceptor *interceptor)

Registers a request interceptor singleton interceptor to intercept URL requests.

The profile does not take ownership of the pointer.

This function was introduced in Qt 5.6.

See also QWebEngineUrlRequestInfo.

### QWebEngineSettings *QWebEngineProfile::settings() const

Returns the default settings for all pages in this profile.

### QString QWebEngineProfile::storageName() const

Returns the storage name for the profile.

The storage name is used to give each profile that uses the disk separate subdirectories for persistent data and cache.

### const QWebEngineUrlSchemeHandler *QWebEngineProfile::urlSchemeHandler(const QByteArray &scheme) const

Returns the custom URL scheme handler register for the URL scheme scheme.

This function was introduced in Qt 5.6.

### bool QWebEngineProfile::visitedLinksContainsUrl(const QUrl &url) const

Returns `true` if url is considered a visited link by this profile.