qt-creator/doc/src/qtquick/qtquick-ui-forms.qdoc

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// NOTE: the sections are not ordered by their logical order to avoid
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// Run the fixnavi.pl script to adjust the links to the index order.
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/*!

    \contentspage index.html
    \page creator-quick-ui-forms.html
    \if defined(qtdesignstudio)
    \previouspage qmldesigner-pathview-editor.html
    \nextpage creator-live-preview.html
    \else
    \previouspage qtquick-iso-icon-browser.html
    \nextpage quick-export-to-qml.html
    \endif

    \title Qt Quick UI Forms

    You can use \QC wizards to create UI forms that have the filename extension
    \e .ui.qml. The UI forms contain a purely declarative subset of the QML
    language. It is recommended that you edit the forms in the \uicontrol Design mode.
    \QC enforces the use of the supported QML features by displaying error
    messages.

    The following features are not supported:

    \list
        \li JavaScript blocks
        \li Other bindings than pure expressions
        \li Signal handlers
        \li States in other items than the root item
        \li Root items that are not derived from \l QQuickItem or \l [QML]{Item}
    \endlist

    The following types are not supported:

    \list
        \li Behavior
        \li Binding
        \li Canvas
        \li Component
        \li Shader Effect
        \li Timer
        \li Transform
        \li Transition
    \endlist

    \section1 Supported Methods

    \QC supports most JavaScript functions that are supported by the QML
    engine, as well as a subset of Qt QML methods.

    This section lists the functions that you can use in \e .ui.qml files.

    \section2 JavaScript Functions

    As a rule of thumb, \e {pure functions} are supported. They only depend on
    and modify states of parameters that are within their scope, and therefore
    always return the same results when given the same parameters. This makes
    it possible to convert and reformat property bindings without breaking the
    \e .ui.qml files.

    The following JavaScript functions are supported:

    \list
        \li \c charAt()
        \li \c charCodeAt()
        \li \c concat()
        \li \c endsWith()
        \li \c includes()
        \li \c indexOf()
        \li \c isFinite()
        \li \c isNaN()
        \li \c lastIndexOf()
        \li \c substring()
        \li \c toExponential()
        \li \c toFixed()
        \li \c toLocaleLowerCase()
        \li \c toLocaleString
        \li \c toLocaleUpperCase()
        \li \c toLowerCase()
        \li \c toPrecision()
        \li \c toString()
        \li \c toUpperCase()
        \li \c valueOf()
    \endlist

    In addition, all functions of the \c Math and \c Date objects are supported.

    For more information, see
    \l{https://doc.qt.io/qt-5/qtqml-javascript-functionlist.html}
    {List of JavaScript Objects and Functions}.

    \section2 Qt QML Methods

    \QC supports color methods, helper methods for creating objects of
    specific data types, and translation methods.

    The following color methods are supported:

    \list
        \li \l{Qt::darker()}{Qt.darker()}
        \li \l{Qt::hsla()}{Qt.hsla()}
        \li \l{Qt::hsva()}{Qt.hsva()}
        \li \l{Qt::lighter()}{Qt.lighter()}
        \li \l{Qt::rgba()}{Qt.rgba()}
        \li \l{Qt::tint()}{Qt.tint()}
    \endlist

    The following helper methods are supported:

    \list
        \li \l{Qt::formatDate()}{Qt.formatDate()}
        \li \l{Qt::formatDateTime()}{Qt.formatDateTime()}
        \li \l{Qt::formatTime()}{Qt.formatTime()}
        \li \l{Qt::matrix4x4()}{Qt.matrix4x4()}
        \li \l{Qt::point()}{Qt.point()}
        \li \l{Qt::quaternion()}{Qt.quaternion()}
        \li \l{Qt::rect()}{Qt.rect()}
        \li \l{Qt::size()}{Qt.size()}
        \li \l{Qt::vector2d()}{Qt.vector2d()}
        \li \l{Qt::vector3d()}{Qt.vector3d()}
        \li \l{Qt::vector4d()}{Qt.vector4d()}
    \endlist

    The following translation methods are supported:

    \list
        \li \l{Qt::}{qsTr()}
        \li \l{Qt::}{qsTranslate()}
        \li \l{Qt::}{qsTranslateNoOp()}
        \li \l{Qt::}{qsTrId()}
        \li \l{Qt::}{qsTrIdNoOp()}
        \li \l{Qt::}{qsTrNoOp()}
    \endlist

    For more information about using the methods, see
    \l{https://doc.qt.io/qt-5/qml-qtqml-qt.html}{Qt QML Methods}.

    \section1 Using Qt Quick UI Forms

    You can edit the forms in the \uicontrol {Form Editor} and
    \uicontrol {Text Editor} tabs in the \uicontrol Design mode. Items that are
    supposed to be used in QML code have to be exported as properties:

    \code
    Item {
        width: 640
        height: 480

        property alias button: button

        Button {
            anchors.centerIn: parent
            id: button
            text: qsTr("Press Me")
        }
    }
    \endcode

    The property alias exports the button to the QML code that uses the form.
    You can use the
    \inlineimage export_checked.png
    (\uicontrol Export) button in the \uicontrol Navigator to export an item as
    a property:

    \image qmldesigner-export-item.png

    In the QML file that uses the form, you can use the \c button property alias
    to implement signal handlers, for example. In the following code snippet,
    the UI form is called \e MainForm.ui.qml:

    \code
    MainForm {
        anchors.fill: parent
        button.onClicked: messageDialog.show(qsTr("Button pressed"))
    }
    \endcode

    You can also assign properties or define behavior or transitions.

    To move from the \uicontrol Design mode directly to the implementation of a
    type in the .qml file, right-click the type in the \uicontrol Navigator and
    select \uicontrol {Go to Implementation} in the context menu.

*/