qt-creator/doc/qtcreator/src/qtquick/qtquick-connection-editor-properties.qdoc

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/*!
    \page quick-dynamic-properties.html
    \previouspage quick-property-bindings.html
    \if defined(qtdesignstudio)
    \nextpage quick-states.html
    \else
    \nextpage quick-connections-backend.html
    \endif

    \title Specifying Dynamic Properties

    Each preset \l{glossary-component}{component} has a set of preset properties
    that you can specify values for. You can add custom properties that would
    not otherwise exist for a particular \l{Component Types}{component type}.
    You bind the properties to dynamic expressions to define global properties
    for a component that can be read by other components. For example, you can
    specify global properties for the root component that you can use in the
    child components.

    For example, to specify spacing between UI elements, you could define a
    margin for a component that does not have a margin property, and then use
    \l{Adding Bindings Between Properties}{bindings} to refer to the value of
    the margin property from other components.

    Similarly, you can add custom properties for your own components that are
    based on preset components.

    You can add properties for components in \l {Connection View} >
    \uicontrol Properties.

    \image qmldesigner-dynamicprops.png "Custom properties in Connection View Custom Properties tab"

    To add properties for a component:

    \list 1
        \li Select \uicontrol View > \uicontrol Views >
            \uicontrol {Connection View} > \uicontrol {Properties}.
        \li Select the \inlineimage plus.png
            (\uicontrol Add) button to add a dynamic property for the currently
            selected component. The component ID is displayed in the \uicontrol Item
            column.
        \li Double-click the value in the \uicontrol Property column to give a
            name to the property. Property names must begin with a lower case
            letter and can only contain letters, numbers, and underscores.
            JavaScript \e {reserved words} are not valid property names.
        \li Double-click the value in the \uicontrol {Property Type} column to
            specify the \l{Supported Property Types}{type of the property}.
        \li Double-click the value in the \uicontrol {Property Value} column
            to specify the value of the property.
    \endlist

    Right-click a property and select \uicontrol {Open Binding Editor} in
    the context menu to bind the value of the property to that of another one
    or to data accessible in the application in \uicontrol {Binding Editor}.
    For more information, see \l{Setting Bindings}.

    \image qmldesigner-binding-editor.png "Binding Editor"

    The properties you add for a component are displayed in the \l Properties
    view when you select a component of that type in \l Navigator or
    \l {Form Editor}.

    \image qtquick-custom-properties.png "Custom properties in Properties view"

    For more information about setting property values in the
    \l Properties view, see \l{Specifying Component Properties}.

    \if defined(qtcreator)
    For an example of using custom properties in an application, see
    \l{Creating a Mobile Application}.
    \endif

    \section1 Supported Property Types

    The following table describes the supported property types:

    \table
    \header
        \li Type
        \li Description
    \row
        \li alias
        \li \l{Property Aliases}{Property alias} that holds a reference to
            another property
    \row
        \li bool
        \li Binary \c true or \c false value
    \row
        \li color
        \li Color value that can be specified by using an SVG color name, such
            as "red", "green", or "lightsteelblue", or a hexadecimal triplet or
            quad in the form "#RRGGBB" and "#AARRGGBB", respectively. For
            example, the color red corresponds to a triplet of "#FF0000" and
            a slightly transparent blue to a quad of "#800000FF".
            In addition, you can use the following Qt functions: \l{Qt::rgba()}
            {Qt.rgba()}, \l{Qt::hsva()}{Qt.hsva()}, \l{Qt::hsla()}{Qt.hsla()},
            \l{Qt::darker()}{Qt.darker()}, \l{Qt::lighter()}{Qt.lighter()}, and
            \l{Qt::tint()}{Qt.tint()}.
    \row
        \li int
        \li Whole integer number, such as 0, 10, or -20
    \row
        \li real
        \li Number with a decimal point
    \row
        \li string
        \li Free form text string
    \row
        \li url
        \li Resource locator, such as a file name. It can be either  absolute,
            (\c http://qt-project.org), or relative  (\c pics/logo.png). A
            relative URL is resolved relative to the URL of the parent
            component.
    \row
        \li variant
        \li Generic property type. For example, variant properties can store
            numbers, strings, objects, arrays, and functions.
    \endtable
*/