Scale

open class Scale : Range, ScaleProtocol

A GtkScale is a slider control used to select a numeric value. To use it, you’ll probably want to investigate the methods on its base class, GtkRange, in addition to the methods for GtkScale itself. To set the value of a scale, you would normally use gtk_range_set_value(). To detect changes to the value, you would normally use the GtkRange::value-changed signal.

Note that using the same upper and lower bounds for the GtkScale (through the GtkRange methods) will hide the slider itself. This is useful for applications that want to show an undeterminate value on the scale, without changing the layout of the application (such as movie or music players).

GtkScale as GtkBuildable

GtkScale supports a custom <marks> element, which can contain multiple <mark> elements. The “value” and “position” attributes have the same meaning as gtk_scale_add_mark() parameters of the same name. If the element is not empty, its content is taken as the markup to show at the mark. It can be translated with the usual ”translatable” and “context” attributes.

CSS nodes

(plain Language Example):

scale[.fine-tune][.marks-before][.marks-after]
├── marks.top
│   ├── mark
│   ┊    ├── [label]
│   ┊    ╰── indicator
┊   ┊
│   ╰── mark
├── [value]
├── contents
│   ╰── trough
│       ├── slider
│       ├── [highlight]
│       ╰── [fill]
╰── marks.bottom
    ├── mark
    ┊    ├── indicator
    ┊    ╰── [label]
    ╰── mark

GtkScale has a main CSS node with name scale and a subnode for its contents, with subnodes named trough and slider.

The main node gets the style class .fine-tune added when the scale is in ‘fine-tuning’ mode.

If the scale has an origin (see gtk_scale_set_has_origin()), there is a subnode with name highlight below the trough node that is used for rendering the highlighted part of the trough.

If the scale is showing a fill level (see gtk_range_set_show_fill_level()), there is a subnode with name fill below the trough node that is used for rendering the filled in part of the trough.

If marks are present, there is a marks subnode before or after the contents node, below which each mark gets a node with name mark. The marks nodes get either the .top or .bottom style class.

The mark node has a subnode named indicator. If the mark has text, it also has a subnode named label. When the mark is either above or left of the scale, the label subnode is the first when present. Otherwise, the indicator subnode is the first.

The main CSS node gets the ‘marks-before’ and/or ‘marks-after’ style classes added depending on what marks are present.

If the scale is displaying the value (see GtkScale:draw-value), there is subnode with name value.

The Scale type acts as a reference-counted owner of an underlying GtkScale instance. It provides the methods that can operate on this data type through ScaleProtocol conformance. Use Scale as a strong reference or owner of a GtkScale instance.

  • Designated initialiser from the underlying `C` data type.
    

    This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    public init(_ op: UnsafeMutablePointer<GtkScale>)

    Parameters

    op

    pointer to the underlying object

  • Designated initialiser from a constant pointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    public init(_ op: UnsafePointer<GtkScale>)

    Parameters

    op

    pointer to the underlying object

  • Optional initialiser from a non-mutating gpointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    override public init!(gpointer op: gpointer?)

    Parameters

    op

    gpointer to the underlying object

  • Optional initialiser from a non-mutating gconstpointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    override public init!(gconstpointer op: gconstpointer?)

    Parameters

    op

    pointer to the underlying object

  • Optional initialiser from a constant pointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    public init!(_ op: UnsafePointer<GtkScale>?)

    Parameters

    op

    pointer to the underlying object

  • Optional initialiser from the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    public init!(_ op: UnsafeMutablePointer<GtkScale>?)

    Parameters

    op

    pointer to the underlying object

  • Designated initialiser from the underlying C data type. Will retain GtkScale. i.e., ownership is transferred to the Scale instance.

    Declaration

    Swift

    @inlinable
    public init(retaining op: UnsafeMutablePointer<GtkScale>)

    Parameters

    op

    pointer to the underlying object

  • Reference intialiser for a related type that implements ScaleProtocol Will retain GtkScale.

    Declaration

    Swift

    @inlinable
    public init<T>(scale other: T) where T : ScaleProtocol

    Parameters

    other

    an instance of a related type that implements ScaleProtocol

  • Unsafe typed initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    override public init<T>(cPointer p: UnsafeMutablePointer<T>)

    Parameters

    cPointer

    pointer to the underlying object

  • Unsafe typed, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    override public init<T>(retainingCPointer cPointer: UnsafeMutablePointer<T>)

    Parameters

    cPointer

    pointer to the underlying object

  • Unsafe untyped initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    override public init(raw p: UnsafeRawPointer)

    Parameters

    p

    raw pointer to the underlying object

  • Unsafe untyped, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    override public init(retainingRaw raw: UnsafeRawPointer)
  • Unsafe untyped initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    public required init(raw p: UnsafeMutableRawPointer)

    Parameters

    p

    mutable raw pointer to the underlying object

  • Unsafe untyped, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    required public init(retainingRaw raw: UnsafeMutableRawPointer)

    Parameters

    raw

    mutable raw pointer to the underlying object

  • Unsafe untyped initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    override public init(opaquePointer p: OpaquePointer)

    Parameters

    p

    opaque pointer to the underlying object

  • Unsafe untyped, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to ScaleProtocol.

    Declaration

    Swift

    @inlinable
    override public init(retainingOpaquePointer p: OpaquePointer)

    Parameters

    p

    opaque pointer to the underlying object

  • Creates a new GtkScale.

    Declaration

    Swift

    @inlinable
    public init<AdjustmentT>(orientation: GtkOrientation, adjustment: AdjustmentT?) where AdjustmentT : AdjustmentProtocol
  • Creates a new scale widget with the given orientation that lets the user input a number between min and max (including min and max) with the increment step. step must be nonzero; it’s the distance the slider moves when using the arrow keys to adjust the scale value.

    Note that the way in which the precision is derived works best if step is a power of ten. If the resulting precision is not suitable for your needs, use gtk_scale_set_digits() to correct it.

    Declaration

    Swift

    @inlinable
    public init(range orientation: GtkOrientation, min: Double, max: Double, step: Double)
  • Creates a new scale widget with the given orientation that lets the user input a number between min and max (including min and max) with the increment step. step must be nonzero; it’s the distance the slider moves when using the arrow keys to adjust the scale value.

    Note that the way in which the precision is derived works best if step is a power of ten. If the resulting precision is not suitable for your needs, use gtk_scale_set_digits() to correct it.

    Declaration

    Swift

    @inlinable
    public static func newWith(range orientation: GtkOrientation, min: Double, max: Double, step: Double) -> Widget!