Struct gtk4::Scale

#[repr(transparent)]
pub struct Scale { /* private fields */ }

A Scale 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, Range, in addition to the methods for Scale itself. To set the value of a scale, you would normally use RangeExt::set_value(). To detect changes to the value, you would normally use the signal::Range::value-changed signal.

Note that using the same upper and lower bounds for the Scale (through the Range 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

Scale supports a custom element, which can contain multiple <mark> elements. The “value” and “position” attributes have the same meaning as ScaleExt::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

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

Scale 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 ScaleExt::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 RangeExt::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 trough 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 property::Scale::draw-value), there is subnode with name value. This node will get the .top or .bottom style classes similar to the marks node.

Accessibility

Scale uses the AccessibleRole::Slider role.

Implements

ScaleExt, RangeExt, WidgetExt, glib::ObjectExt, AccessibleExt, BuildableExt, ConstraintTargetExt, AccessibleRangeExt, OrientableExt, ScaleExtManual, WidgetExtManual, AccessibleExtManual

Implementations

impl Scale

pub const NONE: Option<&'static Scale> = None

pub fn new(
    orientation: Orientation,
    adjustment: Option<&impl IsA<Adjustment>>
) -> Scale

Creates a new Scale.

orientation

the scale’s orientation.

adjustment

the Adjustment which sets the range of the scale, or None to create a new adjustment.

Returns

a new Scale

pub fn with_range(orientation: Orientation, min: f64, max: f64, step: f64) -> Scale

Creates a new scale widget with a range from @min to @max.

The returns scale will have the given orientation and will let 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 ScaleExt::set_digits() to correct it.

orientation

the scale’s orientation.

min

minimum value

max

maximum value

step

step increment (tick size) used with keyboard shortcuts

Returns

a new Scale

pub fn builder() -> ScaleBuilder

Creates a new builder-pattern struct instance to construct Scale objects.

This method returns an instance of ScaleBuilder which can be used to create Scale objects.

Trait Implementations

impl Clone for Scale

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Scale

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Scale

fn default() -> Self

Returns the “default value” for a type.

impl Display for Scale

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Hash for Scale

fn hash<H>(&self, state: &mut H)where
    H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where
    H: Hasher,
    Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: ScaleImpl> IsSubclassable<T> for Scale

fn class_init(class: &mut Class<Self>)

Override the virtual methods of this class for the given subclass and do other class initialization.

fn instance_init(instance: &mut InitializingObject<T>)

Instance specific initialization.

impl Ord for Scale

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl ParentClassIs for Scale

type Parent = Range

impl<OT: ObjectType> PartialEq<OT> for Scale

fn eq(&self, other: &OT) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<OT: ObjectType> PartialOrd<OT> for Scale

fn partial_cmp(&self, other: &OT) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for Scale

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for Scale

impl IsA<Accessible> for Scale

impl IsA<AccessibleRange> for Scale

impl IsA<Buildable> for Scale

impl IsA<ConstraintTarget> for Scale

impl IsA<Orientable> for Scale

impl IsA<Range> for Scale

impl IsA<Widget> for Scale