qt-creator/doc/qtcreator/src/qtquick/library/qtquick-controls.qdoc

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/*!
    \page quick-controls.html
    \previouspage quick-images.html
    \nextpage quick-data-models.html

    \title User Interaction Methods

    You can use a set of basic QML types to add interaction methods to UIs,
    such as performing actions by using a pointing device or the keyboard,
    or flicking the visible area of the screen horizontally or vertically.
    Further, you can use \l{Qt Quick Controls} types to inform users about
    the progress of the application or to gather input from users.

    \image qtquick-designer-qtquickcontrols-types.png "Qt Quick Controls 2 types in Library"

    The following types of controls are available for user interaction:

    \list
        \li \l {Button Controls}
        \li \l {Indicators}
        \li \l {Selectors}
        \li \l {Tab Bar}
        \li \l {Tool Bar}
        \li \l {Summary of User Interaction Methods}
    \endlist

    You can specify values for the properties of components in the
    \uicontrol Properties view. Some properties are common to all components,
    whereas some are common to particular types of controls. Some properties
    are only available for a particular component. The following sections
    describe the basic interaction methods, the controls, and their properties.

    \section1 Basic Interaction Methods

    Users can interact with applications by using pointing devices or the
    keyboard. If the content does not fit the visible area of the screen,
    it can be flicked horizontally or vertically.

    \section2 Mouse Area

    QML uses signals and handlers to deliver mouse interactions. Specifically,
    Qt Quick provides a \uicontrol {Mouse Area} type that developers can use to
    define JavaScript callbacks (also called signal handlers), which accept
    mouse events within a defined area.

    A mouse area receives events within a defined area. One quick way to define
    this area is to \l{Setting Anchors and Margins}{anchor} the mouse area to
    its parent's area. If the parent is a \l {basic-rectangle}{Rectangle} (or
    any component that is derived from an \l {basic-item}{Item}), the mouse area
    will fill the area defined by the parent's dimensions. Alternatively, you
    can define an area smaller or larger than the parent. Several controls,such
    as \l {Button}{buttons}, contain a mouse area.

    A mouse area emits \l{Connecting Objects to Signals}{signals} in response
    to different mouse events:

    \list
        \li \c canceled()
        \li \c clicked()
        \li \c doubleClicked()
        \li \c entered()
        \li \c exited()
        \li \c positionChanged()
        \li \c pressAndHold()
        \li \c pressed()
        \li \c released()
    \endlist

    \if defined(qtcreator)
    A more modern way of handling events from all pointing devices, including
    mouse and touchscreen, is via \l {Qt Quick Input Handlers}.
    \endif

    \section2 Focus Scope

    When a key is pressed or released, a key event is generated and delivered
    to the focused component. If no component has active focus, the key event
    is ignored. If the component with active focus accepts the key event,
    propagation stops. Otherwise the event is sent to the component's parent
    until the event is accepted, or the root item is reached and the event is
    ignored.

    A component has focus when the \uicontrol Focus property in the
    \uicontrol Advanced tab is set to \c true. However, for reusable
    or imported components, this is not sufficient, and you should use
    a \uicontrol {Focus Scope} type.

    Within each focus scope, one object may have focus enabled. If more
    than one component have it enabled, the last component to enable it
    will have the focus and the others are unset, similarly to when there
    are no focus scopes.

    When a focus scope receives active focus, the contained type with
    focus set (if any) also gets the active focus. If this type is
    also a focus scope, both the focus scope and the sub-focused item
    will have active focus.

    The \uicontrol {Focus Scope} type is not a visual type, and therefore the
    properties of its children need to be exposed to the parent item of the
    focus scope. \l{Using Layouts}{Layouts} and \l{Using Positioners}
    {positioners} will use these visual and styling properties to create the
    layout.

    For more information, see \l {Keyboard Focus in Qt Quick}.

    \section2 Flickable

    \uicontrol Flickable places its children on a surface that can be dragged
    and flicked, causing the view onto the child items to scroll. This
    behavior forms the basis of components that are designed to show large
    numbers of child items, such as \uicontrol {List View} and
    \uicontrol {Grid View}. For more information, see \l{List and Grid Views}.

    In traditional user interfaces, views can be scrolled using standard
    controls, such as scroll bars and arrow buttons. In some situations, it
    is also possible to drag the view directly by pressing and holding a
    mouse button while moving the cursor. In touch-based user interfaces,
    this dragging action is often complemented with a flicking action, where
    scrolling continues after the user has stopped touching the view.

    The contents of a flickable component are not automatically clipped. If
    the component is not used as a full-screen item, consider selecting the
    \uicontrol Clip check box in the \uicontrol Visibility section.

    \image qtquick-designer-flickable-properties.png "Flickable properties"

    Users can interact with a flickable component if the \uicontrol Interactive
    property is set to \c true. Set it to \c false to temporarily disable
    flicking. This enables special interaction with the components children.
    For example, you might want to freeze a flickable map while scrolling
    through a pop-up that is a child of the Flickable.

    The \uicontrol {Flick direction} field determines whether the view can be
    flicked horizontally or vertically. Select \uicontrol AutoFlickDirection
    to enable flicking vertically if the content height is not equal to height
    of the flickable and horizontally if the content width is not equal
    to the width of the flickable. Select \uicontrol AutoFlickIfNeeded if
    the content height or width is greater than that of the flickable.

    Specify the maximum velocity for flicking the view in pixels per second in
    the \uicontrol {Max. velocity} field. Specify the rate at which a flick
    will decelerate in the \uicontrol Decelerate field.

    The \uicontrol {Bounds movement} property determines whether the flickable
    will give a feeling that the edges of the view are soft, rather than a hard
    physical boundary. Select \uicontrol StopAtBounds for custom edge effects
    where the contents do not follow drags or flicks beyond the bounds of the
    flickable. Select \uicontrol FollowBoundsBehavior to have the contents
    follow drags or flicks beyond the bounds of the flickable depending on the
    value of the \uicontrol Behavior field.

    In the \uicontrol {Press delay} field, specify the time in milliseconds
    to delay delivering a press to children of a flickable. This can be useful
    when reacting to a press before a flicking action has undesirable effects.
    If the flickable is dragged or flicked before the delay times out,
    the press event will not be delivered. If the button is released
    within the timeout, both the press and release will be delivered.

    \note For nested flickables with press delay set, the press delay of
    outer flickables is overridden by the innermost flickable. If the drag
    exceeds the platform drag threshold, the press event will be delivered
    regardless of this property.

    The \uicontrol {Pixel aligned} property sets the alignment of
    \uicontrol {Content X} and \uicontrol {Content Y} to pixels (\c true)
    or subpixels (\c false). Enable it to optimize for still content or
    moving content with high constrast edges, such as one-pixel-wide lines,
    text, or vector graphics. Disable this property when optimizing for
    animation quality.

    If \uicontrol {Synchronous drag} is set to \c true, then when the mouse or
    touchpoint moves far enough to begin dragging the content, the content will
    jump, so that the content pixel which was under the cursor or touchpoint
    when pressed remains under that point. The default is \c false, which
    provides a smoother experience (no jump) at the cost of losing some of the
    drag distance at the beginning.

    The \uicontrol {Content size} field specifies the dimensions of the
    surface controlled by a flickable. Typically, set the values of the
    \uicontrol W and \uicontrol H fields to the combined size of the items
    placed in the flickable. You can set additional margins around the
    content in the \uicontrol Margins field.

    The \uicontrol Origin field specifies the origin of the content. It
    refers to the top-left position of the content regardless of layout
    direction. Usually, the \uicontrol X and \uicontrol Y are set to 0.
    However, a \l{ListView}{List View} and \l {GridView}{Grid View}
    may have an arbitrary origin due to delegate size variation, or item
    insertion or removal outside the visible region.

    \section1 General Control Properties

    You can set control properties in the \uicontrol Properties view.

    \image qtquick-designer-control-properties.png "Control section in Properties"

    The \uicontrol Enabled check box indicates whether the control is enabled.

    The value of the \uicontrol {Focus policy} field determines whether the
    control accepts focus by tabbing, clicking, and using the mouse wheel.

    Select the \uicontrol Hover and \uicontrol Wheel check boxes to enable the
    control to accept mouse events. The hover value is propagated to all child
    components, unless it has been explicitly set for them.

    \note Take care when enabling wheel events for controls within scrollable
    items, such as \l Flickable, because the control will consume the
    events, and therefore interrupt scrolling of the flickable.

    \uicontrol Spacing is useful for controls that have multiple or repetitive
    building blocks. For example, some \l{Styling Controls}{styles} use spacing
    to determine the distance between the text and indicator of a
    \l {Check Box}. Spacing is not enforced by the controls, so each style may
    interpret it differently, and some may ignore it altogether.

    \section1 Button Controls

    Qt Quick Controls offer a selection of button-like controls for specific
    use cases. The following sections contain guidelines for choosing the button
    most suitable for a use case and discuss the values you can set for button
    properties in the \uicontrol Properties view.

    \image qtquick-designer-button-types.png "Button controls in Form Editor"

    Recommendations for buttons that contain text:

    \list
        \li Keep labels short and concise.
        \li Use the default font unless you have UI guidelines specifying
            otherwise.
        \li If the text is localized, consider how a longer text affects the
            layout.
    \endlist

    For more information about setting text properties, see \l Fonts and
    \l Padding.

    The properties that are shared by all button controls are described in:

    \list
        \li \l {Displaying Text and Icons}
        \li \l {Checking Buttons}
        \li \l {Button Signals}
    \endlist

    \section2 Button

    \image qtquickcontrols2-button.gif "Button"

    \uicontrol Button can be pushed or clicked by users. Typically, buttons
    are used to perform an action or to answer a question. For example, \e OK,
    \e Apply, \e Cancel, \e Close, \e Yes, \e No, and \e Help.

    The button text should be a verb describing the action, or a noun matching
    the title of the popup that will be opened.

    Don't use a button to set state, because a \l Switch is more suitable for
    that purpose.

    Select the \uicontrol Highlighted check box to draw the users' attention
    towards a button. Highlighting a button has no effect on keyboard
    interaction.

    \image qtquickcontrols2-button-highlighted.gif "Highlighted button"

    A flat button typically does not draw a background unless it is pressed or
    checked. To create a flat button, select the \uicontrol Flat check box.

    \image qtquickcontrols2-button-flat.gif "Flat button"

    \section2 Delay Button

    \image qtquickcontrols2-delaybutton.gif "Delay button"

    \uicontrol {Delay Button} incorporates a delay before triggering an action.
    This delay prevents accidental presses.

    Use delay buttons in touch user interfaces and for actions that must be
    triggered with care.

    You can set the delay in milliseconds in the \uicontrol Delay field.

    \section2 Check Box

    \image qtquickcontrols2-checkbox.gif "Check box"

    \uicontrol {Check Box} presents an option button that can be toggled on
    (checked) or off (unchecked). Check boxes are typically used to select
    one or more options from a set of options. For larger sets of options,
    such as those in a list, consider using \uicontrol {Check Delegate} instead.

    \image qtquickcontrols2-checkdelegate.gif "Check delegate"

    Use check boxes to build multi-selection option lists, where any number
    of options can be selected, including none, but the options are not
    mutually exclusive.

    Use a single check box for a yes/no choice, such as when users have to
    accept the terms of service agreement in a dialog. For a single yes/no
    choice, you can also use a \l Switch. If users are choosing between options,
    use a check box. If they are choosing between actions to be taken, a switch
    is recommended.

    The value of the \uicontrol Checked property determines the state of the
    check box. However, in addition to the checked and unchecked states, a
    check box has a third state: \e {partially checked}.

    Select the \uicontrol Tri-state check box to enable the check box to cycle
    between checked, partially checked, and unchecked states when users
    toggle it by using touch, mouse, or keyboard.

    \image qtquickcontrols2-checkbox-tristate.gif "Tri-state check box"

    When options can be grouped, you can use a partially checked check box to
    represent the whole group. Select \uicontrol PartiallyChecked in the
    \uicontrol {Check state} field to indicate that users selected some
    sub-items in the group, but not all of them.

    The checkable options are often listed vertically.

    The check box label should be a statement that the check mark makes true,
    and that the absence of a check mark makes false. Therefore, the check box
    label should not contain a negative statement.

    \section2 Radio Button

    \image qtquickcontrols2-radiobutton.gif "Radio button"

    \uicontrol {Radio Button} is an option button that can be toggled on
    (checked) or off (unchecked). Radio buttons are typically used to select
    one option from a set of options. Selecting an option automatically clears
    the previous selection.

    If there are only two mutually exclusive options, combine them into a single
    \l {Check Box} or a \l Switch.

    \uicontrol {Radio Delegate} is similar to radio button, except that it is
    typically used in views.

    \image qtquickcontrols2-radiodelegate.gif "Radio delegate"

    Recommendations for radio buttons:

    \list
        \li Limit the label text to one line.
        \li Ensure that a sensible default option is checked.
        \li List radio button options vertically.
        \li Keep the list short.
        \li In order to avoid confusion, do not put two groups of radio buttons
            next to each other.
    \endlist

    \section2 Switch

    \image qtquickcontrols2-switch.gif "Switch"

    \uicontrol Switch is an option button that can be dragged or toggled on
    (checked) or off (unchecked). Switches are typically used to select between
    two states: \e on or \e off. For larger sets of options, such as those in a
    list, consider using \uicontrol {Switch Delegate} instead.

    \image qtquickcontrols2-switchdelegate.gif "Switch delegate"

    Use a switch for binary operations that take effect immediately after the
    switch is toggled. For example, use a switch to turn WiFi on or off.

    \section2 Round Button

    \uicontrol {Round Button} is a clickable control that starts an action,
    or  opens or closes a popup. A round button with a square image icon or
    one-letter font icon is circular. A circular round button takes less space
    than a normal button, and can also be used as a floating action button.

    A round button has the same properties as a \l Button.

    \section2 Displaying Text and Icons

    A button can contain text, an icon, or both. Specify the button text in
    the \uicontrol Text field. The value of the \uicontrol Display field
    determines whether only text or an icon is displayed, or when both are
    visible, whether the text is placed beside the icon or under it.

    \image qtquick-designer-abstract-button-properties.png "General button properties"

    \section2 Checking Buttons

    A \e checkable button toggles between checked (on) and unchecked (off) when
    users click on it or press the space bar while the button has active
    focus. Select the \uicontrol Checkable check box to make a button checkable.
    To make the button checked, select the \uicontrol Checked check box.

    Buttons that belong to the same parent item can be mutually exclusive.
    Users can click a button to check it, and the previous selection is
    cleared. Users cannot uncheck the currently checked button by clicking
    it. Instead, they must click another button in the group to set the new
    checked button for that group.

    Radio buttons and tab buttons are mutually exclusive by default. To make
    other types of buttons mutually exclusive, select the \uicontrol Exclusive
    check box.

    If the buttons don't belong to the same parent, checking and unchecking
    buttons does not affect the other buttons in the group.

    \section2 Button Signals

    A button emits the \c clicked() signal when it is activated by users.
    \l{Connecting Objects to Signals}{Connect to this signal} to perform
    the button's action. Buttons provide the following additional signals:
    \c canceled(), \c doubleClicked(), \c pressed(), \c released(), and
    \c pressAndHold() for long presses.

    Select the \uicontrol Auto-repeat check box to repeat the \c pressed(),
    \c released(), and \c clicked() signals while the button is pressed and
    held down. The \c pressAndHold() signal will not be emitted.

    \section1 Indicators

    Qt Quick Controls offer a selection of indicator-like controls, such as
    busy indicator, page indicator, and progress bar, for specific use cases.
    The following sections contain guidelines for choosing the indicator most
    suitable for a use case.

    \image qtquick-designer-indicator-types.png "Indicator types"

    \section2 Busy Indicator

    \image qtquickcontrols2-busyindicator.gif "Busy indicator"

    \uicontrol {Busy Indicator} indicates that an operation is in progress, and
    that the UI has to wait for the operation to complete.

    A busy indicator is similar to an indeterminate \l {Progress Bar}. Both can
    be used to indicate background activity. The main difference is visual, and
    that a progress bar can also present a concrete amount of progress (when it
    can be determined). Due to the visual difference, busy indicators and
    indeterminate progress bars fit in different places in UIs.

    Select the \uicontrol Running check box to make the busy indicator visible.

    Typical places for a busy indicator are:

    \list
        \li In the corner of a \uicontrol {Tool Bar}
        \li As an overlay on top of a \uicontrol Page
        \li On the side of an \uicontrol {Item Delegate}
    \endlist

    \section2 Page Indicator

    \uicontrol {Page Indicator} is used to indicate the currently active page
    in a container of multiple pages. Specify the number of pages in the
    \uicontrol Count field. Select the current page in the \uicontrol Current
    field.

    \target progress-bar-control
    \section2 Progress Bar

    \image qtquickcontrols2-progressbar.gif "Progress bar"

    \uicontrol {Progress Bar} indicates the progress of an operation. You
    can specify the initial value in the \uicontrol Value field, but it
    should be  updated regularly. Specify the range in the \uicontrol From
    and \uicontrol To fields, which can both contain any value.

    \image qtquick-designer-progressbar-properties.png "Progress Bar properties"

    Select the \uicontrol Indeterminate check box when unable to determine the
    size of the item being downloaded, or if the download progress might get
    interrupted due to a network failure.

    \image qtquickcontrols2-progressbar-indeterminate.gif

    The indeterminate mode is similar to a \l {Busy Indicator} in that both can
    be used to indicate background activity. Due to their visual differences,
    indeterminate progress bars and busy indicators fit in different places in
    UIs.

    Typical places for an indeterminate progress bar are:

    \list
        \li At the bottom of a \uicontrol {Tool Bar}
        \li Inline within the content of a \uicontrol Page
        \li In an \uicontrol {Item Delegate} to show the progress
            of a particular item
    \endlist

    \section1 Selectors

    Qt Quick Controls offers a set of selector-like controls, such as sliders,
    dial, sping box, combo box, and tumbler, for specific use cases. The
    following sections contain guidelines for choosing the selector most
    suitable for a use case.

    \image qtquick-designer-selector-types.png "Selector types"

    \target slider-control
    \section2 Slider and Dial

    \image qtquickcontrols2-slider.gif "Slider"

    \uicontrol Slider is used to select a value by sliding a handle along a
    track, whereas \uicontrol {Range Slider} is used to select a range
    specified by two values, by sliding each handle along a track.

    \image qtquickcontrols2-rangeslider.gif "Range slider"

    \uicontrol Dial is similar to a traditional dial knob that is found on
    devices such as stereos or industrial equipment. It allows users to
    specify a value within a range.

    \image qtquickcontrols2-dial-no-wrap.gif "Dial"

    In the \uicontrol From and \uicontrol To fields, set the range of the
    slider or dial. Set the value of the slide handle or dial in the
    \uicontrol Value field. For a range slider, set the initial positions
    of the first and second handles in the \uicontrol {First value} and
    \uicontrol {Second value} fields.

    \image qtquick-designer-range-slider-properties.png "Range slider properties"

    In the \uicontrol {Snap mode} field, set how the slider handles or dial
    behave with regards to the value of the \uicontrol {Step size} field. By
    default, they do not snap to step size, but you can set them to snap to it
    either while being dragged or after being released.

    Select the \uicontrol Live check box to provide live updates of the value
    properties.

    You can set slider orientation to horizontal or vertical in the
    \uicontrol Orientation field.

    For more information, watch the following video:

    \youtube Ed8WS03C-Vk

    A dial supports circular, horizontal, and vertical input modes. For
    applications where fast input is important, the circular input mode is
    useful, as clicking the dial will move it directly to that position.
    For applications where precise input is important, the horizontal and
    vertical input modes are recommended, as these allow small adjustments to
    be made relative to where the dial is clicked. These modes are also better
    for dials where large jumps in values could be unsafe, such as a dial that
    controls audio volume. Set the input mode in the \uicontrol {Input mode}
    field.

    \image qtquick-designer-dial-properties.png "Dial properties"

    \section2 Spin Box

    \image qtquickcontrols2-spinbox.png "Spin Box"

    \uicontrol {Spin box} enables users to choose an integer value by clicking
    the up or down indicator buttons, or by pressing up or down on the keyboard.
    Select the \uicontrol Editable check box to enable users to enter a text
    value in the input field.

    The other spin box properties are similar to those of a dial.

    \section2 Combo Box

    \image qtquickcontrols2-combobox.gif "Combo box"

    \uicontrol {Combo Box} is a combined button and popup list. It provides a
    means of presenting a list of options to users in a way that takes up the
    minimum amount of screen space.

    A combo box is used to select a value from a static multiple-line drop-down
    list. Users cannot add new values, and only one option can be selected.

    Combo box values are provided by a \l{Lists and Other Data Models}
    {data model}. The data model is usually a JavaScript array, a \l ListModel,
    or an integer, but other types of data models are also supported.

    Select the \uicontrol Editable check box to auto-complete combo box text
    based on what is available in the model.

    \image qtquick-designer-combobox-properties.png "Combo box properties"

    When using models that have multiple named roles, specify the role of
    the \uicontrol {Display text} property in the \uicontrol {Text role} field.
    To use a role of the model item that corresponds to the text role, enter
    \c valueRole in the field.

    The \uicontrol Current property is the index of the current item in the
    combo box. The default value is \c -1 when the combo box is empty, and
    \c 0 otherwise.

    A flat combo box does not draw a background unless it is
    interacted with, which makes it blend into the UI. Use flat combo
    boxes on a tool bar, for example, to match the flat look of tool
    buttons. To create a flat combo box, select the \uicontrol Flat
    check box.

    Recommendations for combo boxes:

    \list
        \li If the number of values very large, consider applying a filter.
        \li If the number of values is small, consider using \l {Radio Button},
            so that users can see all options at the same time.
        \li Set a default value, which should be the value that you expect
            to be chosen most often.
    \endlist

    \section2 Tumbler

    \image qtquickcontrols2-tumbler-wrap.gif

    \uicontrol Tumbler allows users to select an option from a spinnable
    \e wheel of items. It is useful when there are too many options to use, for
    example, a \l {Radio Button}, and too few options to require the use of an
    editable \l {Spin Box}. It is convenient in that it requires no keyboard
    usage and wraps around at each end when there are a large number of items.

    Specify the number of visible options in the \uicontrol {Visible count}
    field. Select the index of the current option in the \uicontrol Current
    field.

    \image qtquick-designer-tumbler-properties.png "Tumbler properties"

    To enable wrapping, select the \uicontrol Wrap check box.

    \section1 Tab Bar

    \image qtquickcontrols2-tabbar.gif "Tab Bar"

    \uicontrol {Tab Bar} provides a tab-based navigation model, where users
    can switch between different views or subtasks. A tab bar is commonly
    used as a header or footer of an \l ApplicationWindow. Select the toolbar
    position in the \uicontrol Position field.

    Typically, a tab bar contains a static set of \uicontrol {Tab Button}
    controls that are defined as its children. The \uicontrol Current
    field shows the index of the current tab button. The default value is
    \c -1 when the tab bar is empty, and \c 0 otherwise.

    \image qtquick-designer-tabbar-properties.png "Tab Bar properties"

    You can specify content size in the \uicontrol {Content width} and
    \uicontrol {Content height} fields.

    If the total width of the buttons exceeds the available width of the tab
    bar, it automatically becomes \l{Flickable}{flickable}.

    \image qtquickcontrols2-tabbar-flickable.png

    \section1 Tool Bar

    \image qtquickcontrols2-toolbar.png

    \uicontrol {Tool Bar} contains application-wide and context-sensitive
    actions and controls, such as navigation buttons and search fields. A
    tool bar is commonly used as a header or footer of an \l ApplicationWindow.
    Select the toolbar position in the \uicontrol Position field.

    \image qtquick-designer-toolbar-properties.png "Tool Bar properties"

    \uicontrol {Tool Button} is nearly identical to \l Button, but it has a
    graphical appearance that makes it more suitable for insertion into a
    tool bar.

    A tool bar does not provide a layout of its own, but requires you to
    position its contents, for instance by creating a \l RowLayout. If the
    tool bar contains only one item, it will resize to fit the implicit item
    size. This makes a tool bar particularly suitable for use together with
    \l{Using Layouts}{layouts}. However, you can specify content size in the
    \uicontrol {Content width} and \uicontrol {Content height} fields.

    \uicontrol {Tool Separator} is used to visually distinguish between
    groups of items on a tool bar by separating them with a line. It can
    be used in horizontal or vertical toolbars by setting the value of
    the \uicontrol Orientation field.

    \section1 Summary of User Interaction Methods

    The following table lists the QML types that you can use to add interaction
    methods to UIs. The \e Location column contains the tab name where you can
    find the type in \uicontrol Library. The \e MCU column indicates which types
    are supported on MCUs.

    \table
    \header
        \li Icon
        \li Name
        \li Location
        \li MCU
        \li Purpose
    \row
        \li \inlineimage icons/busyindicator-icon16.png
        \li \l [QtQuickControls]{BusyIndicator}{Busy Indicator}
        \li Qt Quick - Controls 2
        \li
        \li Indicates activity while content is being loaded.
    \row
        \li \inlineimage icons/button-icon16.png
        \li \l [QtQuickControls]{Button}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li A push button that you can associate with an action.
    \row
        \li \inlineimage icons/checkbox-icon16.png
        \li \l [QtQuickControls]{CheckBox}{Check Box}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li An option button that can be toggled on (checked) or off
            (unchecked).
    \row
        \li \inlineimage icons/checkbox-icon16.png
        \li \l [QtQuickControls]{CheckDelegate}{Check Delegate}
        \li Qt Quick - Controls 2
        \li
        \li An item delegate that can be toggled on (checked) or off
            (unchecked).
    \row
        \li \inlineimage icons/combobox-icon16.png
        \li \l [QtQuickControls]{ComboBox}{Combo Box}
        \li Qt Quick - Controls 2
        \li
        \li A combined button and popup list that is populated by using a data
            model.
    \row
        \li \inlineimage icons/delaybutton-icon16.png
        \li \l [QtQuickControls]{DelayButton}{Delay Button}
        \li Qt Quick - Controls 2
        \li
        \li An option button that is triggered when held down long enough.
    \row
        \li \inlineimage icons/dial-icon16.png
        \li \l [QtQuickControls]{Dial}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li A circular dial that is rotated to set a value.
    \row
        \li \inlineimage flickable-icon16.png
        \li \l [QML]{Flickable}
        \li Qt Quick - Basic
        \li \inlineimage ok
        \li Items can be flicked horizontally or vertically.
    \row
        \li \inlineimage focusscope-icon16.png
        \li \l{FocusScope}{Focus Scope}
        \li Qt Quick - Basic
        \li
        \li Assists in keyboard focus handling when building reusable QML
            components.
    \row
        \li \inlineimage mouse-area-icon16.png
        \li \l [QtQuick]{MouseArea}{Mouse Area}
        \li Qt Quick - Basic
        \li \inlineimage ok
        \li Enables simple mouse handling.
    \row
        \li \inlineimage icons/pageindicator-icon16.png
        \li \l [QtQuickControls]{PageIndicator}{Page Indicator}
        \li Qt Quick - Controls 2
        \li
        \li Indicates the indicate the currently active page in a container of
            multiple pages.
    \row
        \li \inlineimage icons/progressbar-icon16.png
        \li \l [QtQuickControls]{ProgressBar}{Progress Bar}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li Indicates the progress of an operation.
    \row
        \li \inlineimage icons/radiobutton-icon16.png
        \li \l [QtQuickControls]{RadioButton}{Radio Button}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li An option button that can be switched on (checked) or off
            (unchecked).
    \row
        \li \inlineimage icons/radiobutton-icon16.png
        \li \l [QtQuickControls]{RadioDelegate}{Radio Delegate}
        \li Qt Quick - Controls 2
        \li
        \li An item delegate that can be toggled on (checked) or off
            (unchecked).
    \row
        \li \inlineimage icons/rangeslider-icon16.png
        \li \l [QtQuickControls]{RangeSlider}{Range Slider}
        \li Qt Quick - Controls 2
        \li
        \li Enables users to select a range of values by sliding two handles
            along a track.
    \row
        \li \inlineimage icons/roundbutton-icon16.png
        \li \l [QtQuickControls]{RoundButton}{Round Button}
        \li Qt Quick - Controls 2
        \li
        \li A push button with rounded corners that you can associate with an
            action.
    \row
        \li \inlineimage icons/slider-icon16.png
        \li \l [QtQuickControls]{Slider}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li Enables users to select a value by sliding a handle along a track.
    \row
        \li \inlineimage icons/spinbox-icon16.png
        \li \l [QtQuickControls]{SpinBox}{Spin Box}
        \li Qt Quick - Controls 2
        \li
        \li Enables users to specify a value by clicking the up or down buttons,
            by pressing up or down on the keyboard, or by entering a value in
            the box.
    \row
        \li \inlineimage icons/switch-icon16.png
        \li \l [QtQuickControls]{Switch}
        \li Qt Quick - Controls 2
        \li \inlineimage ok
        \li An option button that can be toggled on or off.
    \row
        \li \inlineimage icons/switch-icon16.png
        \li \l [QtQuickControls]{SwitchDelegate}{Switch Delegate}
        \li Qt Quick - Controls 2
        \li
        \li An item delegate with a switch indicator that can be toggled on or
            off.
    \row
        \li \inlineimage icons/toolbar-icon16.png
        \li \l [QtQuickControls] {TabBar}{Tab Bar}
        \li Qt Quick - Controls 2
        \li
        \li Enables users to switch between different views or subtasks.
    \row
        \li \inlineimage icons/toolbutton-icon16.png
        \li \l [QtQuickControls]{TabButton}{Tab Button}
        \li Qt Quick - Controls 2
        \li
        \li A button that is functionally similar to \uicontrol Button, but
            provides a look that is more suitable for a \uicontrol {Tab Bar}.
    \row
        \li \inlineimage icons/toolbar-icon16.png
        \li \l [QtQuickControls]{ToolBar}{Tool Bar}
        \li Qt Quick - Controls 2
        \li
        \li A container of application-wide and context sensitive actions and
            controls, such as navigation buttons and search fields.
    \row
        \li \inlineimage icons/toolbutton-icon16.png
        \li \l [QtQuickControls]{ToolButton}{Tool Button}
        \li Qt Quick - Controls 2
        \li
        \li A button that is functionally similar to \uicontrol Button, but
            provides a look that is more suitable for a \uicontrol {Tool Bar}.
    \row
        \li \inlineimage icons/toolseparator-icon16.png
        \li \l [QtQuickControls]{ToolSeparator}{Tool Separator}
        \li Qt Quick - Controls 2
        \li
        \li Separates a group of items from adjacent items on a
            \uicontrol {Tool Bar}.
    \row
        \li \inlineimage icons/tumbler-icon16.png
        \li \l [QtQuickControls]{Tumbler}
        \li Qt Quick - Controls 2
        \li
        \li A spinnable wheel of items that can be selected.
    \endtable
*/