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/*!
   \qmltype TreeView
   \inqmlmodule QtQuick.Controls
   \inherits BasicTableView
   \since 5.5
   \ingroup views
   \ingroup controls
   \brief Provides a tree view with scroll bars, styling and header sections.

   \image treeview.png

   A TreeView implements a tree representation of items from a model.

   Data for each row in the TreeView
   is provided by the model. TreeView accepts models derived from the QAbstractItemModel class.

   You provide title and size of a column header
   by adding a \l TableViewColumn as demonstrated below.

   \code
   TreeView {
       TableViewColumn {
           title: "Name"
           role: "fileName"
           width: 300
       }
       TableViewColumn {
           title: "Permissions"
           role: "filePermissions"
           width: 100
       }
       model: fileSystemModel
   }
   \endcode

   The header sections are attached to values in the \l model by defining
   the model role they attach to. Each property in the model will
   then be shown in their corresponding column.

   You can customize the look by overriding the \l [QML]{TreeView::}{itemDelegate},
   \l {basictableview-rowdelegate}{rowDelegate}, or \l {basictableview-headerdelegate}{headerDelegate} properties.

   The view itself does not provide sorting. This has to
   be done on the model itself. However you can provide sorting
   on the model, and enable sort indicators on headers.

    \list
    \li int sortIndicatorColumn - The index of the current sort column
    \li bool sortIndicatorVisible - Whether the sort indicator should be enabled
    \li enum sortIndicatorOrder - Qt.AscendingOrder or Qt.DescendingOrder depending on state
    \endlist

   You can create a custom appearance for a TreeView by
   assigning a \l {TreeViewStyle}.
*/

/*!
    \qmlproperty Component TreeView::itemDelegate

    This property defines a delegate to draw a specific cell.

    In the item delegate you have access to the following special properties:
    \list
    \li  styleData.selected - if the item is currently selected
    \li  styleData.value - the value or text for this item
    \li  styleData.textColor - the default text color for an item
    \li  styleData.row - the index of the view row
    \li  styleData.column - the index of the view column
    \li  styleData.elideMode - the elide mode of the column
    \li  styleData.textAlignment - the horizontal text alignment of the column
    \li  styleData.pressed - true when the item is pressed
    \li  styleData.hasActiveFocus - true when the row has focus
    \li  styleData.index - the QModelIndex of the current item in the model
    \li  styleData.depth - the depth of the current item in the model
    \li  styleData.isExpanded - true when the item is expanded
    \li  styleData.hasChildren - true if the model index of the current item has or can have children
    \li  styleData.hasSibling - true if the model index of the current item has a sibling
    \endlist

    Example:
    \code
    itemDelegate: Item {
        Text {
            anchors.verticalCenter: parent.verticalCenter
            color: styleData.textColor
            elide: styleData.elideMode
            text: styleData.value
        }
    }
    \endcode

    \note For performance reasons, created delegates can be recycled
    across multiple table rows. This implies that when you make use of implicit
    properties such as \c styleData.row or \c model, these values can change
    after the delegate has been constructed. This means that you should not assume
    that content is fixed when \c Component.onCompleted is called, but instead rely on
    bindings to such properties.
*/

/*!
    \qmlpropertygroup QtQuick.Controls::TreeView::section
    \qmlproperty string TreeView::section.property
    \qmlproperty enumeration TreeView::section.criteria
    \qmlproperty Component TreeView::section.delegate
    \qmlproperty enumeration TreeView::section.labelPositioning

    These properties determine the section labels.

    \sa {QtQuick::ListView::section}{ListView.section}
*/

/*!
    \qmlproperty QAbstractItemModel TreeView::model
    This property holds the model providing data for the tree view.

    The model provides the set of data that is displayed by the view.
    The TreeView accept models derived from the QAbstractItemModel class.
*/

/*!
    \qmlproperty QModelIndex TreeView::rootIndex
    The model index of the root item in the tree view. The root item is the
    parent item to the view's top-level items. Only items descending from the
    root item will be visible in the view.

    Its default value is an invalid QModelIndex, which means the whole
    model data is shown by the tree view (assigning \c undefined to this
    proprety resets it to its default value.)

    \since QtQuick.Controls 1.5
*/

/*!
    \qmlproperty QModelIndex TreeView::currentIndex
    The model index of the current row in the tree view.
*/

/*!
    \qmlproperty ItemSelectionModel TreeView::selection

    By default the selection model is \c null and only single selection is supported.

    To use a different selection mode as described in \l {BasicTableView::selectionMode}{selectionMode},
    an ItemSelectionModel must by set to the selection.

    For example:

    \code
    TreeView {
       model: myModel
       selection: ItemSelectionModel {
            model: myModel
       }
       TableViewColumn {
           role: "name"
           title: "Name
       }
    }
    \endcode

    \sa {BasicTableView::selectionMode}{selectionMode}

*/

/*!
    \qmlsignal TreeView::activated(QModelIndex index)

    Emitted when the user activates a row in the tree by mouse or keyboard interaction.
    Mouse activation is triggered by single- or double-clicking, depending on the platform.

    \a index is the model index of the activated row in the tree.

    \note This signal is only emitted for mouse interaction that is not blocked in the row or item delegate.

    The corresponding handler is \c onActivated.
*/

/*!
    \qmlsignal TreeView::clicked(QModelIndex index)

    Emitted when the user clicks a valid row in the tree by single clicking

    \a index is the model index of the clicked row in the tree.

    \note This signal is only emitted if the row or item delegate does not accept mouse events.

    The corresponding handler is \c onClicked.
*/

/*!
    \qmlsignal TreeView::doubleClicked(QModelIndex index)

    Emitted when the user double clicks a valid row.

    \a index is the model index of the double clicked row in the tree.

    \note This signal is only emitted if the row or item delegate does not accept mouse events.

    The corresponding handler is \c onDoubleClicked.
*/

/*!
    \qmlsignal TreeView::pressAndHold(QModelIndex index)

    Emitted when the user presses and holds a valid row in the tree.

    \a index is the model index of the pressed row in the tree.

    \note This signal is only emitted if the row or item delegate does not accept mouse events.

    The corresponding handler is \c onPressAndHold.
*/

/*!
    \qmlsignal TreeView::expanded(QModelIndex index)

    Emitted when a valid row in the tree is expanded, displaying its children.

    \a index is the model index of the expanded row in the tree.

    \note This signal is only emitted if the row or item delegate does not accept mouse events.

    The corresponding handler is \c onExpanded.
*/

/*!
    \qmlsignal TreeView::collapsed(QModelIndex index)

    Emitted when a valid row in the tree is collapsed, hiding its children.

    \a index is the model index of the collapsed row in the tree.

    \note This signal is only emitted if the row or item delegate does not accept mouse events.

    The corresponding handler is \c onCollapsed.
*/

/*!
    \qmlmethod bool TreeView::isExpanded(QModelIndex index)

    Returns true if the model item at \a index is expanded; otherwise returns false.

    \sa {expanded}, {expand}
*/

/*!
    \qmlmethod void TreeView::collapse(QModelIndex index)

    Collapses the model item specified by the \a index.

    \sa {collapsed}, {isExpanded}
*/

/*!
    \qmlmethod void TreeView::expand(QModelIndex index)

    Expands the model item specified by the \a index.

    \sa {expanded}, {isExpanded}
*/

/*!
    \qmlmethod QModelIndex TreeView::indexAt( int x, int y )

    Returns the model index of the visible row at the point \a x, \e y in content
    coordinates. If there is no visible row at the point specified, an invalid
    \l QModelIndex is returned.

    \note This method should only be called after the component has completed.
*/
