Trait GridRow 

pub trait GridRow:
    Send
    + Sync
    + 'static {
    type Key: Clone + Eq + Hash + Debug + Send + Sync + 'static;
    type Column: GridColumns;

    // Required methods
    fn key(&self) -> &Self::Key;
    fn value(&self, column: Self::Column) -> CellValue<'_>;

    // Provided methods
    fn changed_columns(&self, previous: &Self, out: &mut ColumnSet) { ... }
    fn parent_key(&self) -> Option<&Self::Key> { ... }
    fn change_direction(
        &self,
        previous: &Self,
        column: Self::Column,
    ) -> Option<ChangeDirection> { ... }
}

A row of the grid. Rows are immutable snapshots shared through Arc.

Required Associated Types

type Key: Clone + Eq + Hash + Debug + Send + Sync + 'static

The domain key of the row.

type Column: GridColumns

The columns of the row type.

Required Methods

fn key(&self) -> &Self::Key

The key of this row.

fn value(&self, column: Self::Column) -> CellValue<'_>

The value of a column. Called for visible cells on every frame and for every row when sorting: it must not allocate or lock.

Provided Methods

fn changed_columns(&self, previous: &Self, out: &mut ColumnSet)

Adds to out the columns whose values differ from previous.

The default compares every column with GridRow::value; override it when the producer knows cheaper what changed. Called by ingest, and by a writer whose upsert takes the place of a pending upsert of the same key (WriteCoalescing::ByKey), under the store’s write lock: it must not lock.

fn parent_key(&self) -> Option<&Self::Key>

The parent row’s key in a tree view; None for a root. Called in the background while a tree is built, and by ingest (or a writer whose upsert merges into a pending one) on every replacement of the row, to compare it with the previous version (ChangeSet::has_parent_change): it must not allocate or lock.

fn change_direction( &self, previous: &Self, column: Self::Column, ) -> Option<ChangeDirection>

The direction of column after a change from previous.

The default is Up or Down when both values are numbers, by CellValue::cmp_total, and None otherwise or when they are equal. Override it for a column whose rise is bad news, such as a spread. Called for changed columns only, by ingest or by a writer whose upsert merges into a pending one: it must not allocate or lock.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors