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/*!
\page qmlbasicelements.html
\ingroup qml-features
\contentspage QML Features
\previouspage QML Features
\nextpage {QML Basic Types}{Data Types}

\title QML Basic Elements

QML's basic elements allow the easy inclusion of objects into the
scene.

\section1 Basic Elements
This is a list of some of the elements readily available for users.
\list
\li \l {Item}
\li \l {Rectangle}
\li \l {Image}
\li \l {Text}
\li \l {TextInput}
\li \l {TextEdit}
\li \l {FocusScope}
\li \l {Component}
\li \l {MouseArea}
\endlist

For a complete list of QML elements, please visit the \l {QML Elements} page.

\section1 Properties and Qt Declarative Module

When using QML elements, keep in mind that elements may possess properties that
other elements also possess. This is because QML and its underlying engine is
implemented in C++ using Qt. More importantly, the chain of property inheritance
is directly due to QML's use of the \l {Qt Declarative Module} and Qt's
\l {Meta-Object System}{meta-object} and \l {The Property System}{property} systems. For example, visual elements that have C++ implementation are sublcasses of
\l {QDeclarativeItem}. As a result, elements such as \l {Rectangle} and
\l {Text} elements inherit properties such as \c clip and \c smooth.

\section1 Item Element

Many QML elements inherit \l Item properties. \c Item possesses important properties
such as \c focus, \c children, and dimension properties such as \c width and
\c height. Although \c Item has physical properties, it is not a visual element.
Using \c Item as the top-level QML element (as the screen) will not produce a
visual result, use the \l {Rectangle} element instead. Use the \c Item to create
opacity effects, such as when creating an invisible container to hold other
components.

\section1 Rectangle Element

The \l Rectangle element is the basic visual element, for displaying different
types of items onto the screen. The \c Rectangle is customizable and utilizes
other elements such as \l Gradient and \l BorderImage for displaying advanced
customized graphics.

\section1 Image Element

To insert an image into a QML scene, merely declare an \l Image element. The
\c Image element can load images in formats supported by Qt.

\section1 Text Elements

The \l Text and \l TextEdit elements display formatted text onto the screen.
\c TextEdit features multi-line editing while the \l TextInput element is for
single line text input.

\keyword qml-top-level-component
\section1 Using Elements as the Top-Level Component

For creating components (or displaying a simple scene), there are different
elements that could be used as the top-level component. To display a simple scene,
a \l Rectangle as the top-level component may suffice. \l Rectangle,
\l FocusScope, \l Component, \l {QML:QtObject} {QtObject}, \l Item, are some of
the commonly used elements as the top-level component.

When importing components, the top-level component is important because the
top-level component's properties are the only properties exposed to the parent.

For example, a \c Button component may be implemented using different elements as
its top-level component. When this component is loaded into another QML scene,
the component will retain the top-level component's properties. If a non-visual
component is the top-level component, the visual properties should be aliased to
the top-level to display the component properly.

For more information on how to build upon QML elements, see the
\l{Importing Reusable Components} document.
*/
