ScrollIndicator QML Type | Qt Quick Controls 5.15.1

- Qt 5.15
- Qt Quick Controls
- QML Types
- ScrollIndicator QML Type
- Qt 5.15.1 Reference Documentation

# ScrollIndicator QML Type

Vertical or horizontal non-interactive scroll indicator. More...

Import Statement: | import QtQuick.Controls 2.15
Since: | Qt 5.7
Inherits: | Control

- List of all members, including inherited members

## Properties

- active : bool
- horizontal : bool
- minimumSize : real
- orientation : enumeration
- position : real
- size : real
- vertical : bool
- visualPosition : real
- visualSize : real

## Attached Properties

- horizontal : ScrollIndicator
- vertical : ScrollIndicator

## Detailed Description

ScrollIndicator is a non-interactive indicator that indicates the current scroll position. A scroll indicator can be either vertical or horizontal, and can be attached to any Flickable, such as ListView and GridView.

     Flickable {
         // ...
         ScrollIndicator.vertical: ScrollIndicator { }
     }

## Attaching ScrollIndicator to a Flickable

Note: When ScrollIndicator is attached vertically or horizontally to a Flickable, its geometry and the following properties are automatically set and updated as appropriate:

- orientation
- position
- size
- active

An attached ScrollIndicator re-parents itself to the target Flickable. A vertically attached ScrollIndicator resizes itself to the height of the Flickable, and positions itself to either side of it based on the layout direction. A horizontally attached ScrollIndicator resizes itself to the width of the Flickable, and positions itself to the bottom. The automatic geometry management can be disabled by specifying another parent for the attached ScrollIndicator. This can be useful, for example, if the ScrollIndicator should be placed outside a clipping Flickable. This is demonstrated by the following example:

     Flickable {
         id: flickable
         clip: true
         // ...
         ScrollIndicator.vertical: ScrollIndicator {
             parent: flickable.parent
             anchors.top: flickable.top
             anchors.left: flickable.right
             anchors.bottom: flickable.bottom
         }
     }

## Binding the Active State of Horizontal and Vertical Scroll Indicators

Horizontal and vertical scroll indicators do not share the active state with each other by default. In order to keep both indicators visible whilst scrolling to either direction, establish a two-way binding between the active states as presented by the following example:

     Flickable {
         anchors.fill: parent

         contentWidth: parent.width * 2
         contentHeight: parent.height * 2

         ScrollIndicator.horizontal: ScrollIndicator { id: hbar; active: vbar.active }
         ScrollIndicator.vertical: ScrollIndicator { id: vbar; active: hbar.active }
     }

## Non-attached Scroll Indicators

It is possible to create an instance of ScrollIndicator without using the attached property API. This is useful when the behavior of the attached scoll indicator is not sufficient or a Flickable is not in use. In the following example, horizontal and vertical scroll indicators are used to indicate how far the user has scrolled over the text (using MouseArea instead of Flickable):

     Rectangle {
         id: frame
         clip: true
         width: 160
         height: 160
         border.color: "black"
         anchors.centerIn: parent

         Text {
             id: content
             text: "ABC"
             font.pixelSize: 169

             MouseArea {
                 id: mouseArea
                 drag.target: content
                 drag.minimumX: frame.width - width
                 drag.minimumY: frame.height - height
                 drag.maximumX: 0
                 drag.maximumY: 0
                 anchors.fill: content
             }
         }

         ScrollIndicator {
             id: verticalIndicator
             active: mouseArea.pressed
             orientation: Qt.Vertical
             size: frame.height / content.height
             position: -content.y / content.height
             anchors { top: parent.top; right: parent.right; bottom: parent.bottom }
         }

         ScrollIndicator {
             id: horizontalIndicator
             active: mouseArea.pressed
             orientation: Qt.Horizontal
             size: frame.width / content.width
             position: -content.x / content.width
             anchors { left: parent.left; right: parent.right; bottom: parent.bottom }
         }
     }

See also ScrollBar, Customizing ScrollIndicator, and Indicator Controls.

## Property Documentation

active : bool

This property holds whether the indicator is active, that is, when the attached Flickable is moving.

It is possible to keep both horizontal and vertical indicators visible while scrolling in either direction.

This property is automatically set when the scroll indicator is attached to a flickable.

[read-only] horizontal : bool

This property holds whether the scroll indicator is horizontal.

This property was introduced in QtQuick.Controls 2.3 (Qt 5.10).

See also orientation.

minimumSize : real

This property holds the minimum size of the indicator, scaled to `0.0 - 1.0`.

This property was introduced in QtQuick.Controls 2.4 (Qt 5.11).

See also size, visualSize, and visualPosition.

orientation : enumeration

This property holds the orientation of the indicator.

Possible values:

Constant | Description
--- | ---
`Qt.Horizontal` | Horizontal
`Qt.Vertical` | Vertical (default)

This property is automatically set when the scroll indicator is attached to a flickable.

See also horizontal and vertical.

position : real

This property holds the position of the indicator, scaled to `0.0 - 1.0`.

This property is automatically set when the scroll indicator is attached to a flickable.

See also Flickable::visibleArea and visualPosition.

size : real

This property holds the size of the indicator, scaled to `0.0 - 1.0`.

This property is automatically set when the scroll indicator is attached to a flickable.

See also Flickable::visibleArea, minimumSize, and visualSize.

[read-only] vertical : bool

This property holds whether the scroll indicator is vertical.

This property was introduced in QtQuick.Controls 2.3 (Qt 5.10).

See also orientation.

visualPosition : real

This property holds the effective visual position of the indicator, which may be limited by the minimum size.

This property was introduced in QtQuick.Controls 2.4 (Qt 5.11).

See also position and minimumSize.

visualSize : real

This property holds the effective visual size of the indicator, which may be limited by the minimum size.

This property was introduced in QtQuick.Controls 2.4 (Qt 5.11).

See also size and minimumSize.

## Attached Property Documentation

ScrollIndicator.horizontal : ScrollIndicator

This property attaches a horizontal scroll indicator to a Flickable.

     Flickable {
         contentWidth: 2000
         ScrollIndicator.horizontal: ScrollIndicator { }
     }

See also Attaching ScrollIndicator to a Flickable.

ScrollIndicator.vertical : ScrollIndicator

This property attaches a vertical scroll indicator to a Flickable.

     Flickable {
         contentHeight: 2000
         ScrollIndicator.vertical: ScrollIndicator { }
     }

See also Attaching ScrollIndicator to a Flickable.