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diff --git a/src/qml/doc/src/qml/network.qdoc b/src/qml/doc/src/qml/network.qdoc deleted file mode 100644 index 1df6f51202..0000000000 --- a/src/qml/doc/src/qml/network.qdoc +++ /dev/null @@ -1,236 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). -** Contact: http://www.qt-project.org/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** GNU Free Documentation License -** 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. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms -** and conditions contained in a signed written agreement between you -** and Nokia. -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! -\page qml-network.html -\ingroup qml-features -\title Resource Loading and Network Transparency in QML -\brief about loading files and resources accross a network - -QML supports network transparency by using URLs (rather than file names) for all -references from a QML document to other content. This means that anywhere a URL source is expected, -QML can handle remote resources as well as local ones, for example in the following image source: - -\qml -Image { - source: "http://www.example.com/images/logo.png" -} -\endqml - -Since a \e relative URL is the same -as a relative file, development of QML on regular file systems remains simple: - -\qml -Image { - source: "images/logo.png" -} -\endqml - -Network transparency is supported throughout QML, for example: - -\list -\li Fonts - the \c source property of FontLoader is a URL -\li WebViews - the \c url property of WebView (obviously!) -\endlist - -Even QML types themselves can be on the network - if the \l {QML Viewer} is used to load -\tt http://example.com/mystuff/Hello.qml and that content refers to a type "World", the engine -will load \tt http://example.com/mystuff/qmldir and resolve the type just as it would for a local file. -For example if the qmldir file contains the line "World World.qml", it will load -\tt http://example.com/mystuff/World.qml -Any other resources that \tt Hello.qml referred to, usually by a relative URL, would -similarly be loaded from the network. - - -\section1 Relative vs. Absolute URLs - -Whenever an object has a property of type URL (QUrl), assigning a string to that -property will actually assign an absolute URL - by resolving the string against -the URL of the document where the string is used. - -For example, consider this content in \tt{http://example.com/mystuff/test.qml}: - -\qml -Image { - source: "images/logo.png" -} -\endqml - -The \l Image source property will be assigned \tt{http://example.com/mystuff/images/logo.png}, -but while the QML is being developed, in say \tt C:\\User\\Fred\\Documents\\MyStuff\\test.qml, it will be assigned -\tt C:\\User\\Fred\\Documents\\MyStuff\\images\\logo.png. - -If the string assigned to a URL is already an absolute URL, then "resolving" does -not change it and the URL is assigned directly. - - -\section1 Progressive Loading - -Because of the declarative nature of QML and the asynchronous nature of network resources, -objects which reference network resource generally change state as the network resource loads. -For example, an Image with a network source will initially have -a \c width and \c height of 0, a \c status of \c Loading, and a \c progress of 0.0. -While the content loads, the \c progress will increase until -the content is fully loaded from the network, -at which point the \c width and \c height become the content size, the \c status becomes \c Ready, and the \c progress reaches 1.0. -Applications can bind to these changing states to provide visual progress indicators where appropriate, or simply -bind to the \c width and \c height as if the content was a local file, adapting as those bound values change. - -Note that when objects reference local files they immediately have the \c Ready status, but applications wishing -to remain network transparent should not rely on this. Future versions of QML may also use asynchronous local file I/O -to improve performance. - - -\section1 Accessing Network Services - -QML types such as XmlListModel, and JavaScript classes like XMLHttpRequest are intended -entirely for accessing network services, which usually respond with references to -content by URLs that can then be used directly in QML. For example, using these facilities -to access an on-line photography service would provide the QML application with URLs to -photographs, which can be directly set on an \l Image \c source property. - -See the \tt examples/quick/flickr for a real demonstration of this. - - -\section1 Configuring the Network Access Manager - -All network access from QML is managed by a QNetworkAccessManager set on the QQmlEngine which executes the QML. -By default, this is an unmodified Qt QNetworkAccessManager. You may set a different manager by -providing a QQmlNetworkAccessManagerFactory and setting it via -QQmlEngine::setNetworkAccessManagerFactory(). -For example, the \l {QML Viewer} sets a QQmlNetworkAccessManagerFactory which -creates QNetworkAccessManager that trusts HTTP Expiry headers to avoid network cache checks, -allows HTTP Pipelining, adds a persistent HTTP CookieJar, a simple disk cache, and supports proxy settings. - - -\section1 QRC Resources - -One of the URL schemes built into Qt is the "qrc" scheme. This allows content to be compiled into -the executable using \l{The Qt Resource System}. Using this, an executable can reference QML content -that is compiled into the executable: - -\code - QQuickView *canvas = new QQuickView; - canvas->setUrl(QUrl("qrc:/dial.qml")); -\endcode - -The content itself can then use relative URLs, and so be transparently unaware that the content is -compiled into the executable. - - -\section1 Limitations - -The \c import statement is only network transparent if it has an "as" clause. - -More specifically: -\list -\li \c{import "dir"} only works on local file systems -\li \c{import libraryUri} only works on local file systems -\li \c{import "dir" as D} works network transparently -\li \c{import libraryUrl as U} works network transparently -\endlist - -\section1 XMLHttpRequest - -\target XMLHttpRequest - -QML script supports the XMLHttpRequest object, which can be used to asynchronously obtain -data from over a network. - -The XMLHttpRequest API implements the same \l {http://www.w3.org/TR/XMLHttpRequest/}{W3C standard} -as many popular web browsers with following exceptions: -\list -\li QML's XMLHttpRequest does not enforce the same origin policy. -\li QML's XMLHttpRequest does not support \e synchronous requests. -\endlist - -Additionally, the \c responseXML XML DOM tree currently supported by QML is a reduced subset -of the \l {http://www.w3.org/TR/DOM-Level-3-Core/}{DOM Level 3 Core} API supported in a web -browser. The following objects and properties are supported by the QML implementation: - -\table -\header -\li \b {Node} -\li \b {Document} -\li \b {Element} -\li \b {Attr} -\li \b {CharacterData} -\li \b {Text} - -\row -\li -\list -\li nodeName -\li nodeValue -\li nodeType -\li parentNode -\li childNodes -\li firstChild -\li lastChild -\li previousSibling -\li nextSibling -\li attributes -\endlist - -\li -\list -\li xmlVersion -\li xmlEncoding -\li xmlStandalone -\li documentElement -\endlist - -\li -\list -\li tagName -\endlist - -\li -\list -\li name -\li value -\li ownerElement -\endlist - -\li -\list -\li data -\li length -\endlist - -\li -\list -\li isElementContentWhitespace -\li wholeText -\endlist - -\endtable - -The \l{declarative/xml/xmlhttprequest}{XMLHttpRequest example} demonstrates how to -use the XMLHttpRequest object to make a request and read the response headers. - -*/ |