Struct GridView 

pub struct GridView<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> { /* private fields */ }

View controller for 2D indexable data (grid)

This widget generates a view over a list of data items via a DataClerk. “View widgets” are constructed via a Driver to represent visible data items. These view widgets are reassigned as required when the grid is scrolled, keeping the number of widgets in use roughly proportional to the number of data items within the view.

Each view widget has an Id corresponding to its current data item, and may handle events and emit messages like other widegts. See Driver documentation for more on event handling.

This widget is Scrollable, supporting keyboard, wheel and drag scrolling. You may wish to wrap this widget with ScrollBars.

Optionally, data items may be selected; see Self::set_selection_mode. If enabled, SelectionMsg messages are reported; view widgets may emit kas::messages::Select to have themselves be selected.

Messages

kas::messages::SetScrollOffset may be used to set the scroll offset.

Implementations

impl<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> GridView<C, V>

pub fn new(clerk: C, driver: V) -> Self

Construct a new instance

pub fn clerk(&self) -> &C

Access the data clerk

pub fn clerk_mut(&mut self) -> &mut C

Access the data clerk (mutably)

Changes to the clerk must be notified with an update to the GridView, for example using ConfigCx::update, EventCx::update or Action::UPDATE.

pub fn view_range(&self) -> Range<GridIndex>

Get the range of visible data items

Data items within this range may be visible (or should at least be allocated some pixel within the controller’s view).

pub fn selection_mode(&self) -> SelectionMode

Get the current selection mode

pub fn set_selection_mode(&mut self, cx: &mut EventState, mode: SelectionMode)

Set the current selection mode

By default, selection is disabled. If enabled, items may be selected and deselected via mouse-click/touch or via a view widget emitting Select.

On selection and deselection, a SelectionMsg message is emitted.

pub fn with_selection_mode(self, mode: SelectionMode) -> Self

Set the initial selection mode (inline)

See Self::set_selection_mode documentation.

pub fn selection_style(&self) -> SelectionStyle

Get the current selection style

pub fn set_selection_style( &mut self, cx: &mut EventState, style: SelectionStyle, )

Set the current selection style

By default, SelectionStyle::Highlight is used. Other modes may add margin between elements.

pub fn with_selection_style(self, style: SelectionStyle) -> Self

Set the selection style (inline)

See Self::set_selection_style documentation.

pub fn selected_iter(&self) -> impl Iterator<Item = &C::Key> + '_

Read the list of selected entries

With mode SelectionMode::Single this may contain zero or one entry; use selected_iter().next() to extract only the first (optional) entry.

pub fn is_selected(&self, key: &C::Key) -> bool

Check whether an entry is selected

pub fn clear_selected(&mut self, cx: &mut EventState)

Clear all selected items

pub fn select(&mut self, cx: &mut EventState, key: C::Key) -> bool

Directly select an item

Does nothing if Self::selection_mode is SelectionMode::None. Does not verify the validity of key. Does not send SelectionMsg messages.

Returns true if newly selected, false if already selected. Fails if selection mode does not permit selection or if the key is invalid.

pub fn deselect(&mut self, cx: &mut EventState, key: &C::Key) -> bool

Directly deselect an item

Returns true if deselected, false if not previously selected or if the key is invalid.

pub fn with_num_visible(self, cols: u32, rows: u32) -> Self

Set the preferred number of items visible (inline)

This affects the (ideal) size request and whether children are sized according to their ideal or minimum size but not the minimum size.

Trait Implementations

impl<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> Events for GridView<C, V>

fn mouse_over_icon(&self) -> Option<CursorIcon>

The mouse cursor icon to use on mouse over

fn make_child_id(&mut self, _: usize) -> Id

Make an identifier for a child

fn configure(&mut self, cx: &mut ConfigCx<'_>)

Configure self

fn configure_recurse(&mut self, cx: &mut ConfigCx<'_>, data: &Self::Data)

Configure children

fn update(&mut self, cx: &mut ConfigCx<'_>, data: &C::Data)

Update self using input data

fn update_recurse(&mut self, _: &mut ConfigCx<'_>, _: &Self::Data)

Update children

fn handle_event( &mut self, cx: &mut EventCx<'_>, data: &C::Data, event: Event<'_>, ) -> IsUsed

Handle an Event

fn handle_messages(&mut self, cx: &mut EventCx<'_>, data: &C::Data)

Handler for messages from children/descendants

fn handle_scroll( &mut self, cx: &mut EventCx<'_>, data: &C::Data, scroll: Scroll, )

Handler for scrolling

const REDRAW_ON_MOUSE_OVER: bool = false

Does this widget have a different appearance on mouse over?

fn handle_mouse_over(&mut self, cx: &mut EventCx<'_>, state: bool)

Mouse focus handler

impl<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> Layout for GridView<C, V>

fn size_rules(&mut self, sizer: SizeCx<'_>, axis: AxisInfo) -> SizeRules

Get size rules for the given axis

fn set_rect(&mut self, cx: &mut ConfigCx<'_>, rect: Rect, hints: AlignHints)

Set size and position

fn draw(&self, draw: DrawCx<'_>)

Draw a widget and its children

fn rect(&self) -> Rect

Get the widget’s region

fn try_probe(&self, coord: Coord) -> Option<Id>

Probe a coordinate for a widget’s Id

impl<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> Scrollable for GridView<C, V>

fn content_size(&self) -> Size

Get the content size (the inner size of the scrolled pane)

fn max_scroll_offset(&self) -> Offset

Get the maximum scroll offset

fn scroll_offset(&self) -> Offset

Get the current scroll offset

fn set_scroll_offset(&mut self, cx: &mut EventCx<'_>, offset: Offset) -> Offset

Set the scroll offset

impl<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> Tile for GridView<C, V>

fn role(&self, cx: &mut dyn RoleCx) -> Role<'_>

Describe the widget’s role

fn child_indices(&self) -> ChildIndices

Get child indices available to recursion

fn get_child(&self, index: usize) -> Option<&dyn Tile>

Access a child as a dyn Tile, if available

fn find_child_index(&self, id: &Id) -> Option<usize>

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

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

Get translation of child index relative to this widget

fn probe(&self, coord: Coord) -> Id

Probe a coordinate for a widget’s Id

fn as_tile(&self) -> &dyn Tile

Get as a dyn Tile

fn id_ref(&self) -> &Id

Get a reference to the widget’s identifier

fn identify(&self) -> IdentifyWidget<'_>

Return a Display-able widget identifier

fn nav_next(&self, reverse: bool, from: Option<usize>) -> Option<usize>

Navigation in spatial order

fn id(&self) -> Id

Get the widget’s identifier

fn navigable(&self) -> bool

Whether this widget supports navigation focus

fn tooltip(&self) -> Option<&str>

Tooltip

fn role_child_properties(&self, cx: &mut dyn RoleCx, index: usize)

Specify additional role properties for child index

impl<C: DataClerk<GridIndex>, V: Driver<C::Key, C::Item>> Widget for GridView<C, V>

type Data = <C as DataClerk<GridIndex>>::Data

Input data type

fn child_node<'n>( &'n mut self, data: &'n C::Data, index: usize, ) -> Option<Node<'n>>

Access a child as a Node, if available

fn as_node<'__a>(&'__a mut self, data: &'__a Self::Data) -> Node<'__a>

Erase type