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This is primarily useful when setting the properties of an item when the property has one of the following types: \list \o Color \o Rect \o Point \o Size \o Vector3D \endlist There are also string based constructors for these types, see \l{basicqmltypes.html}{Qml Types}. \section3 Qt.rgba(qreal red, qreal green, qreal blue, qreal alpha) This function returns a Color with the specified \c red, \c green, \c blue and \c alpha components. All components should be in the range 0-1 inclusive. \section3 Qt.hsla(qreal hue, qreal saturation, qreal lightness, qreal alpha) This function returns a Color with the specified \c hue, \c saturation, \c lightness and \c alpha components. All components should be in the range 0-1 inclusive. \section3 Qt.rect(int x, int y, int width, int height) This function returns a Rect with the top-left corner at \c x, \c y and the specified \c width and \c height. \section3 Qt.point(int x, int y) This function returns a Point with the specified \c x and \c y coordinates. \section3 Qt.size(int width, int height) This function returns as Size with the specified \c width and \c height. \section3 Qt.vector3d(real x, real y, real z) This function returns a Vector3D with the specified \c x, \c y and \c z. \section2 Functions The Qt object also contains the following miscellaneous functions which expose Qt functionality for use in QML. \section3 Qt.lighter(color baseColor) This function returns a color 50% lighter than \c baseColor. See QColor::lighter() for further details. \section3 Qt.darker(color baseColor) This function returns a color 50% darker than \c baseColor. See QColor::darker() for further details. \section3 Qt.tint(color baseColor, color tintColor) This function allows tinting one color with another. The tint color should usually be mostly transparent, or you will not be able to see the underlying color. The below example provides a slight red tint by having the tint color be pure red which is only 1/16th opaque. \qml Rectangle { x: 0; width: 80; height: 80; color: "lightsteelblue" } Rectangle { x: 100; width: 80; height: 80; color: Qt.tint("lightsteelblue", "#10FF0000") } \endqml \image declarative-rect_tint.png Tint is most useful when a subtle change is intended to be conveyed due to some event; you can then use tinting to more effectively tune the visible color. \section3 Qt.closestAngle(number fromAngle, number toAngle) This function returns an equivalent angle to toAngle, such that the difference between fromAngle and toAngle is never more than 180 degrees. This is useful when animating angles using a NumberAnimation, which does not know about equivalent angles, when you always want to take the shortest path. For example, the following would rotate myItem counterclockwise from 350 degrees to 10 degrees, for a total of 340 degrees of rotation. \qml NumberAnimation { target: myItem; property: "rotation"; from: 350; to: 10 } \endqml while the following would rotate myItem clockwise from 350 degrees to 370 degrees (which is visually equivilant to 10 degrees), for a total of 20 degrees of rotation. \qml NumberAnimation { target: myItem; property: "rotation"; from: 350; to: Qt.closetAngle(350, 10) } \endqml \section3 Qt.playSound(url soundLocation) This function plays the audio file located at \c soundLocation. Only .wav files are supported. \section3 Qt.openUrlExternally(url target) This function attempts to open the specified \c target url in an external application, based on the user's desktop preferences. It will return true if it succeeds, and false otherwise. \section3 Qt.md5(data) This function returns a hex string of the md5 hash of \c data. \section1 Dynamic Object Creation The following functions on the global object allow you to dynamically create QML items from files or strings. You can also dynamically create objects in a declarative manner, using items such as ListView, \l Repeater and \l Loader. \section2 createComponent(url file) This function takes the URL of a QML file as its only argument. It returns a component object which can be used to create and load that QML file. Example QML script is below. Remember that QML files that might be loaded over the network cannot be expected to be ready immediately. \code var component; var sprite; function finishCreation(){ if(component.isReady()){ sprite = component.createObject(); if(sprite == 0){ // Error Handling }else{ sprite.parent = page; sprite.x = 200; //... } }else if(component.isError()){ // Error Handling } } component = createComponent("Sprite.qml"); if(component.isReady()){ finishCreation(); }else{ component.statusChanged.connect(finishCreation); } \endcode If you are certain the files will be local, you could simplify to \code component = createComponent("Sprite.qml"); sprite = component.createObject(); if(sprite == 0){ // Error Handling console.log(component.errorsString()); }else{ sprite.parent = page; sprite.x = 200; //... } \endcode If you want to just create an arbitrary string of QML, instead of loading a QML file, consider the createQmlObject() function. \section2 createQmlObject(string qml, object parent, string filepath) Creates a new object from the specified string of QML. It requires a second argument, which is the id of an existing QML object to use as the new object's parent. If a third argument is provided, this is used for error reporting as the filepath that the QML came from. Example (where targetItem is the id of an existing QML item): \code newObject = createQmlObject('import Qt 4.6; Rectangle {color: "red"; width: 20; height: 20}', targetItem, "dynamicSnippet1"); \endcode This function is intended for use inside QML only. It is intended to behave similarly to eval, but for creating QML elements. Returns the created object, or null if there is an error. In the case of an error, details of the error are output using qWarning(). Note that this function returns immediately, and therefore may not work if the QML loads new components. If you are trying to load a new component, for example from a QML file, consider the createComponent() function instead. 'New components' refers to external QML files that have not yet been loaded, and so it is safe to use createQmlObject to load built-in components. \section1 Asynchronous JavaScript and XML QML script supports the XMLHttpRequest object, which can be used to asynchronously obtain data from over a network. \section2 XMLHttpRequest() In QML you can construct an XMLHttpRequest object just like in a web browser! TODO: Real documentation for this object. \section1 Offline Storage API The \c openDatabase() and related functions provide the ability to access local offline storage in an SQL database. These databases are user-specific and QML-specific. They are stored in the \c Databases subdirectory of QmlEngine::offlineStoragePath(), currently as SQLite databases. The API conforms to the Synchronous API of the HTML5 Web Database API, \link http://www.w3.org/TR/2009/WD-webdatabase-20091029/ W3C Working Draft 29 October 2009\endlink. The API can be used from JavaScript functions in your QML: \quotefile declarative/sql/hello.qml When a database is first created, an INI file is also created specifying its characteristics: \table \header \o \bold {Key} \o \bold {Value} \row \o Name \o The name of the database passed to \c openDatabase() \row \o Version \o The version of the database passed to \c openDatabase() \row \o Description \o The description of the database passed to \c openDatabase() \row \o EstimatedSize \o The estimated size of the database passed to \c openDatabase() \row \o Driver \o Currently "QSQLITE" \endtable This data can be used by application tools. */