Interface: DataMethods<Data, Context>
Type parameters
| Name | Type |
|---|---|
Data | any |
Context | any |
Properties
prepend
• prepend: (data: Data[]) => void
Prepends additional items to the existing data in the list, while preserving the scroll position.
Type declaration
▸ (data): void
Parameters
| Name | Type | Description |
|---|---|---|
data | Data[] | The data to prepend. |
Returns
void
append
• append: (data: Data[], scrollToBottom?: AutoscrollToBottom<Data, Context>) => void
Appends additional items to the existing data in the list, while optionally updating the scroll position. See the AutoscrollToBottom type for more information.
Type declaration
▸ (data, scrollToBottom?): void
Parameters
| Name | Type | Description |
|---|---|---|
data | Data[] | The data to append. |
scrollToBottom? | AutoscrollToBottom<Data, Context> | Specifies the behavior when the list is scrolled to the bottom. You can pass a boolean, a ScrollBehavior, or a function that returns a ScrollBehavior. |
Returns
void
map
• map: (callbackfn: (data: Data, index: number) => Data, autoscrollToBottomBehavior?: ScrollBehavior | { location: () => ItemLocation }) => void
Updates the data in the list by applying a mapping function to each item. Optionally, you can specify a scroll behavior if the state change displaces the list (for example, if the item size increases).
Type declaration
▸ (callbackfn, autoscrollToBottomBehavior?): void
Parameters
| Name | Type | Description |
|---|---|---|
callbackfn | (data: Data, index: number) => Data | A function that maps the data items. |
autoscrollToBottomBehavior? | ScrollBehavior | { location: () => ItemLocation } | Specifies the behavior to use to scroll to the bottom if necessary. |
Returns
void
findAndDelete
• findAndDelete: (predicate: (item: Data, index: number) => boolean) => void
Deletes items from the list data that match the predicate.
Type declaration
▸ (predicate): void
Parameters
| Name | Type |
|---|---|
predicate | (item: Data, index: number) => boolean |
Returns
void
findIndex
• findIndex: (predicate: (item: Data, index: number, data: Data[]) => boolean) => number
Finds the index of the first item that matches the predicate. If no elements satisfy the testing function, -1 is returned.
Type declaration
▸ (predicate): number
Parameters
| Name | Type |
|---|---|
predicate | (item: Data, index: number, data: Data[]) => boolean |
Returns
number
find
• find: (predicate: (item: Data, index: number, data: Data[]) => boolean) => Data
Finds the first item that matches the predicate. If no elements satisfy the testing function, undefined is returned.
Type declaration
▸ (predicate): Data
Parameters
| Name | Type |
|---|---|
predicate | (item: Data, index: number, data: Data[]) => boolean |
Returns
Data
replace
• replace: (data: Data[], options?: { initialLocation?: ItemLocation ; purgeItemSizes?: boolean ; suppressItemMeasure?: boolean }) => void
Completely replaces the data in the list with the new data.
Optionally, you can specify an initial scroll location after the data has been replaced.
See the ItemLocation type for more information.
Setting the purgeItemSizes flag to true will clear the item size cache and force the list to remeasure the items.
The suppressItemMeasure flag will prevent the list from measuring the items after the data has been replaced.
Type declaration
▸ (data, options?): void
Parameters
| Name | Type | Description |
|---|---|---|
data | Data[] | The data to replace. |
options? | Object | the location to scroll to after the data has been replaced and whether to purge the item sizes. |
options.initialLocation? | ItemLocation | - |
options.purgeItemSizes? | boolean | - |
options.suppressItemMeasure? | boolean | - |
Returns
void
insert
• insert: (data: Data[], offset: number, scrollToBottom?: AutoscrollToBottom<Data, Context>) => void
Inserts the provided data at the specified offset, optionally updating the scroll position.
Type declaration
▸ (data, offset, scrollToBottom?): void
Parameters
| Name | Type | Description |
|---|---|---|
data | Data[] | The data to append. |
offset | number | The index that the first item in the data will be inserted at. e.g. [1,2,3] with offset 10 will insert the data at index 10, 11, and 12 and shift the rest of the existing data. |
scrollToBottom? | AutoscrollToBottom<Data, Context> | Specifies the behavior when the list is scrolled to the bottom. You can pass a boolean, a ScrollBehavior, or a function that returns a ScrollBehavior. |
Returns
void
deleteRange
• deleteRange: (offset: number, count: number) => void
Deletes a range of items from the list data.
Type declaration
▸ (offset, count): void
Parameters
| Name | Type | Description |
|---|---|---|
offset | number | The index of the first item to delete. |
count | number | The number of items to delete. |
Returns
void
batch
• batch: (callback: () => void, scrollToBottom?: AutoscrollToBottom<Data, Context>) => void
Batches the data operations in the provided callback in a single render cycle.
Type declaration
▸ (callback, scrollToBottom?): void
Parameters
| Name | Type | Description |
|---|---|---|
callback | () => void | The callback that performs the data operations. |
scrollToBottom? | AutoscrollToBottom<Data, Context> | Specifies the behavior when the list is scrolled to the bottom. You can pass a boolean, a ScrollBehavior, or a function that returns a ScrollBehavior. |
Returns
void
get
• get: () => Data[]
Gets a shallow copy of the current data in the list.
Type declaration
▸ (): Data[]
Returns
Data[]
getCurrentlyRendered
• getCurrentlyRendered: () => Data[]
Gets the currently rendered data items.
Type declaration
▸ (): Data[]
Returns
Data[]