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diff --git a/doc/src/qtquick1/basictypes.qdoc b/doc/src/qtquick1/basictypes.qdoc deleted file mode 100644 index 2cc8859dc2..0000000000 --- a/doc/src/qtquick1/basictypes.qdoc +++ /dev/null @@ -1,597 +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 qdeclarativebasictypes.html -\inqmlmodule QtQuick 1 - \ingroup qml-features - \contentspage QML Features - \previouspage {QML Basic Elements} - \nextpage Property Binding - \title QML Basic Types - - QML has a set of primitive types, as listed below, that are used throughout - the \l {QML Elements}. - - \annotatedlist qmlbasictypes - - To create additional types, such as data types created in C++, read the - \l{Extending QML Functionalities using C++} article. -*/ - -/*! - \qmlbasictype int - \ingroup qmlbasictypes - - \brief An integer is a whole number, e.g. 0, 10, or -20. - - An integer is a whole number, e.g. 0, 10, or -20. The possible \c - int values range from around -2000000000 to around 2000000000, - although most elements will only accept a reduced range (which they - mention in their documentation). - - Example: - \qml - Item { width: 100; height: 200 } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype bool - \ingroup qmlbasictypes - - \brief A boolean is a binary true/false value. - - A boolean is a binary true/false value. - - Example: - \qml - Item { focus: true; clip: false } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype real - \ingroup qmlbasictypes - - \brief A real number has a decimal point, e.g. 1.2 or -29.8. - - A real number has a decimal point, e.g. 1.2 or -29.8. - - Example: - \qml - Item { width: 100.45; height: 150.82 } - \endqml - - \note In QML all reals are stored in single precision, \l - {http://en.wikipedia.org/wiki/IEEE_754} {IEEE floating point} - format. - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype double - \ingroup qmlbasictypes - - \brief A double number has a decimal point and is stored in double precision. - - A double number has a decimal point and is stored in double precision, \l - {http://en.wikipedia.org/wiki/IEEE_754} {IEEE floating point} - format. - - Example: - \qml - Item { - property double number: 32155.2355 - } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype string - \ingroup qmlbasictypes - - \brief A string is a free form text in quotes, e.g. "Hello world!". - - A string is a free form text in quotes, e.g. "Hello world!". - - Example: - \qml - Text { text: "Hello world!" } - \endqml - - Strings have a \c length attribute that holds the number of - characters in the string. - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype url - \ingroup qmlbasictypes - - \brief A URL is a resource locator, like a file name. - - A URL is a resource locator, like a file name. It can be either - absolute, e.g. "http://qt.nokia.com", or relative, e.g. - "pics/logo.png". A relative URL is resolved relative to the URL of - the component where the URL is converted from a JavaScript string - expression to a url property value. - - Example: - \qml - Image { source: "pics/logo.png" } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype color - \ingroup qmlbasictypes - - \brief A color is a standard color name in quotes. - - A color is a standard color name in quotes. It is normally specified - as an \l {http://www.w3.org/TR/SVG/types.html#ColorKeywords} {SVG - color name}. These names include colors like "red", "green" and - "lightsteelblue". - - If the color you want isn't part of this list, colors can also be - specified in hexidecimal triplets or quads that take the form \c - "#RRGGBB" and \c "#AARRGGBB" respectively. For example, the color - red corresponds to a triplet of \c "#FF0000" and a slightly - transparent blue to a quad of \c "#800000FF". - - Example: - \div{float-right} - \inlineimage declarative-colors.png - \enddiv - \snippet doc/src/snippets/declarative/colors.qml colors - - Or with the \l{QML:Qt::rgba()}{Qt.rgba()}, \l{QML:Qt::hsla()}{Qt.hsla()}, \l{QML:Qt::darker()}{Qt.darker()}, - \l{QML:Qt::lighter()}{Qt.lighter()} or \l{QML:Qt::tint()}{Qt.tint()} functions: - - \qml - Rectangle { color: Qt.rgba(0.5, 0.5, 0, 1) } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype point - \ingroup qmlbasictypes - - \brief A point type has x and y attributes. - - A \c point type has \c x and \c y attributes. - - To create a \c point value, specify it as a "x,y" string: - - \qml - CustomObject { myPointProperty: "0,20" } - \endqml - - Or use the \l{QML:Qt::point()}{Qt.point()} function: - - \qml - CustomObject { myPointProperty: Qt.point(0, 20) } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype size - \ingroup qmlbasictypes - - \brief A size type has width and height attributes - - A \c size type has \c width and \c height attributes. - - For example, to read the \l {Image::sourceSize} \c size property: - - \qml - Column { - Image { id: image; source: "logo.png" } - Text { text: image.sourceSize.width + "," + image.sourceSize.height } - } - \endqml - - To create a \c size value, specify it as a "width x height" string: - - \qml - LayoutItem { preferredSize: "150x50" } - \endqml - - Or use the \l{QML:Qt::size()}{Qt.size()} function: - - \qml - LayoutItem { preferredSize: Qt.size(150, 50) } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype rect - \ingroup qmlbasictypes - - \brief A rect type has x, y, width and height attributes. - - A \c rect type has \c x, \c y, \c width and \c height attributes. - - For example, to read the \l {Item::childrenRect.x}{Item::childrenRect} \c rect property: - \qml - Rectangle { - width: childrenRect.width - height: childrenRect.height - - Rectangle { width: 100; height: 100 } - } - \endqml - - To create a \c rect value, specify it as a "x, y, width x height" string: - - \qml - CustomObject { myRectProperty: "50,50,100x100" } - \endqml - - Or use the \l{QML:Qt::rect()}{Qt.rect()} function: - - \qml - CustomObject { myRectProperty: Qt.rect(50, 50, 100, 100) } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype date - \ingroup qmlbasictypes - - \brief A date is specified as "YYYY-MM-DD". - - To create a \c date value, specify it as a "YYYY-MM-DD" string: - - Example: - \qml - MyDatePicker { minDate: "2000-01-01"; maxDate: "2020-12-31" } - \endqml - - To read a date value returned from a C++ extension class, use - \l{QML:Qt::formatDate()}{Qt.formatDate()} and \l{QML:Qt::formatDateTime()}{Qt.formatDateTime()}. - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype time - \ingroup qmlbasictypes - - \brief A time is specified as "hh:mm:ss". - - A time is specified as "hh:mm:ss". - - Example: - \qml - MyTimePicker { time: "14:22:15" } - \endqml - - To read a time value returned from a C++ extension class, use - \l{QML:Qt::formatTime()}{Qt.formatTime()} and \l{QML:Qt::formatDateTime()}{Qt.formatDateTime()}. - - \sa {QML Basic Types} - */ - -/*! - \qmlbasictype font - \ingroup qmlbasictypes - - \brief A font type has the properties of a QFont. - - A font type has the properties of a QFont. The properties are: - - \list - \o \c string font.family - \o \c bool font.bold - \o \c bool font.italic - \o \c bool font.underline - \o \c real font.pointSize - \o \c int font.pixelSize - \endlist - - Example: - \qml - Text { font.family: "Helvetica"; font.pointSize: 13; font.bold: true } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype action - \ingroup qmlbasictypes - - \brief The action type has all the properties of QAction. - - The action type has all the properties of QAction. The properties - are: - - \list - \o \c slot action.trigger - invoke the action - \o \c bool action.enabled - true if the action is enabled - \o \c string action.text - the text associated with the action - \endlist - - Actions are used like this: - - \qml - Item { - MouseArea { onClicked: myaction.trigger() } - State { name: "enabled"; when: myaction.enabled == true } - Text { text: someaction.text } - } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype list - \ingroup qmlbasictypes - - \brief A list of objects. - - A list type contains a list of objects. While not technically - a basic type, QML supports lists of object types. When used - from QML, the engine automatically appends each value to the list. - Items in the list can be accessed by index using the usual - \c listName[index] syntax. - - For example, the \l Item class contains a list property named - children that can be used like this: - - \qml - Item { - children: [ - Item { id: child1 }, - Rectangle { id: child2; width: 200 }, - Text { id: child3 } - ] - - Component.onCompleted: { - console.log("Width of child rectangle:", children[1].width) - } - } - \endqml - \c child1, \c child2 and \c child3 will be added to the children list - in the order in which they appear. - - List \l {Property Binding}{properties} can be created as a - \c variant type, or as a \c list<Type> type, where \c Type is the - type of the object in the list: - - \qml - Item { - property list<Rectangle> rects: [ - Rectangle { width: 100; height: 100}, - Rectangle { width: 200; height: 200} - ] - } - \endqml - - A list property can only contain values that match (or are derived from) the - specified \c Type. - - While the \c rects property can be reassigned to a different list value (including - an empty list), its individual values cannot be modified. See the \l variant type - documentation for details. - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype variant - \ingroup qmlbasictypes - - \brief A variant type is a generic property type. - - A variant is a generic property type. A variant type property can hold - any of the \l {QML Basic Types}{basic type} values: - - \qml - Item { - property variant aNumber: 100 - property variant aString: "Hello world!" - property variant aBool: false - } - \endqml - - A \c variant type property can also hold an image or pixmap. - A \c variant which contains a QPixmap or QImage is known as a - "scarce resource" and the declarative engine will attempt to - automatically release such resources after evaluation of any JavaScript - expression which requires one to be copied has completed. - - Clients may explicitly release such a scarce resource by calling the - "destroy" method on the \c variant property from within JavaScript. They - may also explicitly preserve the scarce resource by calling the - "preserve" method on the \c variant property from within JavaScript. - For more information regarding the usage of a scarce resource, please - see \l{Scarce Resources in JavaScript}. - - Finally, the \c variant type can also hold: - - \list - \o An array of \l {QML Basic Types}{basic type} values - \o A map of key-value pairs with \l {QML Basic Types}{basic-type} values - \endlist - - For example, below is an \c items array and an \c attributes map. Their - contents can be examined using JavaScript \c for loops. Individual array - values are accessible by index, and individual map values are accessible - by key: - - \qml - Item { - property variant items: [1, 2, 3, "four", "five"] - property variant attributes: { 'color': 'red', 'width': 100 } - - Component.onCompleted: { - for (var i=0; i<items.length; i++) - console.log(items[i]) - - for (var prop in attributes) - console.log(prop, "=", attributes[prop]) - } - } - \endqml - - While this is a convenient way to store array and map-type values, you - must be aware that the \c items and \c attributes properties above are \e not - QML objects (and certainly not JavaScript object either) and the key-value - pairs in \c attributes are \e not QML properties. Rather, the \c items - property holds an array of values, and \c attributes holds a set of key-value - pairs. Since they are stored as a set of values, instead of as an object, - their contents \e cannot be modified individually: - - \qml - Item { - property variant items: [1, 2, 3, "four", "five"] - property variant attributes: { 'color': 'red', 'width': 100 } - - Component.onCompleted: { - items[0] = 10 - console.log(items[0]) // This will still be '1'! - attributes.color = 'blue' - console.log(attributes.color) // This will still be 'red'! - } - } - \endqml - - Additionally, since \c items and \c attributes are not QML objects, changing - their individual values do not trigger property change notifications. If - the above example had \c onNumberChanged or \c onAnimalChanged signal - handlers, they would not have been called. If, however, the \c items or - \c attributes properties themselves were reassigned to different values, then - such handlers would be called. - - One way to "update" the contents of an array or map is to copy the property - to a JavaScript object, modify the copy as desired, and then reassign the - property to the updated copy. Note, however, that this is not efficient. - In the example below, which reassigns the \c attributes property, the \e entire - set of key-value pairs must be serialized and deserialized every time it is - copied between a JavaScript object and a QML property: - - \qml - Item { - property variant attributes: { 'color': 'red', 'width': 100 } - - Component.onCompleted: { - // Change the value of attributes.color to 'blue': - var temp = attributes // copy all values to 'temp' - temp.color = 'blue' - attributes = temp // copy all values back to 'attributes' - } - } - \endqml - - Since this operation is inefficient, if a list or map should be modifiable, - it is better to use alternative approaches. For example, you could implement - a custom C++ list element, or write to a JavaScript object defined from - within a JavaScript file. - - JavaScript programmers should also note that when a JavaScript object is - copied to an array or map property, the \e contents of the object (that is, - its key-value properties) are copied, rather than the object itself. The - property does not hold a reference to the original JavaScript object, and - extra data such as the object's JavaScript prototype chain is also lost in - the process. - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype vector3d - \ingroup qmlbasictypes - - \brief A vector3d type has x, y, and z attributes. - - A \c vector3d type has \c x, \c y, and \c z attributes. - - To create a \c vector3d value, specify it as a "x,y,z" string: - - \qml - Rotation { angle: 60; axis: "0,1,0" } - \endqml - - or with the \l{QML:Qt::vector3d()}{Qt.vector3d()} function: - - \qml - Rotation { angle: 60; axis: Qt.vector3d(0, 1, 0) } - \endqml - - or as separate \c x, \c y, and \c z components: - - \qml - Rotation { angle: 60; axis.x: 0; axis.y: 1; axis.z: 0 } - \endqml - - \sa {QML Basic Types} -*/ - -/*! - \qmlbasictype enumeration - \ingroup qmlbasictypes - - \brief An enumeration type consists of a set of named values. - - An enumeration type consists of a set of named values. - - An enumeration value may be specified as either a string: - \qml - Text { horizontalAlignment: "AlignRight" } - \endqml - - or as \c {<Element>.<value>}: - \qml - Text { horizontalAlignment: Text.AlignRight } - \endqml - - The second form is preferred. - - \sa {QML Basic Types} -*/ |