Struct kas_widgets::ScrollBar

pub struct ScrollBar<D: Directional> { /* fields omitted */ }

A scroll bar

Scroll bars allow user-input of a value between 0 and a defined maximum, and allow the size of the handle to be specified.

Implementations

impl<D: Directional + Default> ScrollBar<D>

pub fn new() -> Self

Construct a scroll bar

Default values are assumed for all parameters.

impl<D: Directional> ScrollBar<D>

pub fn new_with_direction(direction: D) -> Self

Construct a scroll bar with the given direction

Default values are assumed for all parameters.

pub fn with_limits(self, max_value: i32, handle_value: i32) -> Self

Set the initial page length

See ScrollBar::set_limits.

pub fn with_value(self, value: i32) -> Self

Set the initial value

pub fn set_limits(&mut self, max_value: i32, handle_value: i32) -> TkAction

Set the page limits

The max_value parameter specifies the maximum possible value. (The minimum is always 0.) For a scroll region, this should correspond to the maximum possible offset.

The handle_value parameter specifies the size of the handle relative to the maximum value: the handle size relative to the length of the scroll bar is handle_value / (max_value + handle_value). For a scroll region, this should correspond to the size of the visible region. The minimum value is 1.

The choice of units is not important (e.g. can be pixels or lines), so long as both parameters use the same units.

Returns TkAction::REDRAW if a redraw is required.

pub fn max_value(&self) -> i32

Read the current max value

See also the ScrollBar::set_limits documentation.

pub fn handle_value(&self) -> i32

Read the current handle value

See also the ScrollBar::set_limits documentation.

pub fn value(&self) -> i32

Get the current value

pub fn set_value(&mut self, value: i32) -> TkAction

Set the value

Trait Implementations

impl<D: Clone + Directional> Clone for ScrollBar<D>

fn clone(&self) -> ScrollBar<D>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<D: Debug + Directional> Debug for ScrollBar<D>

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

Formats the value using the given formatter.

impl<D: Default + Directional> Default for ScrollBar<D>

fn default() -> ScrollBar<D>

Returns the “default value” for a type.

impl<D: Directional> Handler for ScrollBar<D>

type Msg = i32

Type of message returned by this widget

fn activation_via_press(&self) -> bool

Generic handler: translate presses to activations

fn focus_on_key_nav(&self) -> bool

Generic handler: focus rect on key navigation

fn handle(&mut self, mgr: &mut Manager<'_>, event: Event) -> Response<Self::Msg>

Handle an event and return a user-defined message

impl<D: Directional> Layout for ScrollBar<D>

fn size_rules(
    &mut self,
    size_handle: &mut dyn SizeHandle,
    axis: AxisInfo
) -> SizeRules

Get size rules for the given axis

fn set_rect(&mut self, mgr: &mut Manager<'_>, rect: Rect, align: AlignHints)

Apply a given rect to self

fn spatial_nav(
    &mut self,
    _: &mut Manager<'_>,
    _: bool,
    _: Option<usize>
) -> Option<usize>

Navigation in spatial order

fn find_id(&self, coord: Coord) -> Option<WidgetId>

Find a widget by coordinate

fn draw(
    &self,
    draw_handle: &mut dyn DrawHandle,
    mgr: &ManagerState,
    disabled: bool
)

Draw a widget and its children

fn translation(&self, _child_index: usize) -> Offset

Get translation of a child

impl<D: Directional> SendEvent for ScrollBar<D>

fn send(
    &mut self,
    mgr: &mut Manager<'_>,
    id: WidgetId,
    event: Event
) -> Response<Self::Msg>

Send an event

impl<D: Directional> WidgetChildren for ScrollBar<D>

fn first_id(&self) -> WidgetId

Get the first identifier of self or any children

fn num_children(&self) -> usize

Get the number of child widgets

fn get_child(&self, _index: usize) -> Option<&dyn WidgetConfig>

Get a reference to a child widget by index, or None if the index is out of bounds.

fn get_child_mut(&mut self, _index: usize) -> Option<&mut dyn WidgetConfig>

Mutable variant of get

fn record_first_id(&mut self, _id: WidgetId)

Record first identifier

fn is_ancestor_of(&self, id: WidgetId) -> bool

Check whether id is a descendant

fn find_child(&self, id: WidgetId) -> Option<usize>

Find the child which is an ancestor of this id, if any

fn find_leaf(&self, id: WidgetId) -> Option<&(dyn WidgetConfig + 'static)>

Find the leaf (lowest descendant) with this id, if any

fn find_leaf_mut(
    &mut self,
    id: WidgetId
) -> Option<&mut (dyn WidgetConfig + 'static)>

Find the leaf (lowest descendant) with this id, if any

fn walk_children<F>(&self, f: F) where
    F: FnMut(&(dyn WidgetConfig + 'static)), 

Walk through all widgets, calling f once on each.

fn walk_children_mut<F>(&mut self, f: F) where
    F: FnMut(&mut (dyn WidgetConfig + 'static)), 

Walk through all widgets, calling f once on each.

impl<D: Directional> WidgetConfig for ScrollBar<D>

fn key_nav(&self) -> bool

Is this widget navigable via Tab key?

fn hover_highlight(&self) -> bool

Does this widget have hover-state highlighting?

fn cursor_icon(&self) -> CursorIcon

Which cursor icon should be used on hover?

fn configure(&mut self, &mut Manager<'_>)

Configure widget

fn configure_recurse(&mut self, cmgr: ConfigureManager<'_, '_>)

Configure self and children

impl<D: Directional> WidgetCore for ScrollBar<D>

fn as_any(&self) -> &dyn Any

Get self as type Any

fn as_any_mut(&mut self) -> &mut dyn Any

Get self as type Any (mutable)

fn core_data(&self) -> &CoreData

Get direct access to the CoreData providing property storage.

fn core_data_mut(&mut self) -> &mut CoreData

fn widget_name(&self) -> &'static str

Get the name of the widget struct

fn as_widget(&self) -> &dyn WidgetConfig

Erase type

fn as_widget_mut(&mut self) -> &mut dyn WidgetConfig

Erase type

fn id(&self) -> WidgetId

Get the widget’s numeric identifier

fn is_disabled(&self) -> bool

Get whether the widget is disabled

fn set_disabled(&mut self, disabled: bool) -> TkAction

Set the disabled state of a widget

fn with_disabled(self, disabled: bool) -> Self

Set disabled state (chaining)

fn rect(&self) -> Rect

Get the widget’s region, relative to its parent.

fn input_state(&self, mgr: &ManagerState, disabled: bool) -> InputState

Construct InputState

impl<D: Directional> Widget for ScrollBar<D>