DataSource

This section describes how you can provide a data set and how a DikeGrid instance treats that data set.

Live examples

In-Memory DataSource live example.

Custom DataSource live example.

Specifying data

Every DikeGrid instance accepts data from an Array, Observable< Array>, a DikeGridDataSource, or simply a DataSource.

Remember, the DataSource definition is an abstract class with two methods: connect() and disconnect(). Therefore, you can provide an instance of a class that derives from the DataSource class.

Depending on the data you provide, there are two types of DataSource: an In-Memory DataSource and a Custom DataSource.

Wrapping data entries

It does not matter how you provide your data set. The DikeGrid will wrap every data entry in a DikeGridDataRowEntry instance.

The DikeGridDataRowEntry wrapper helps to know several features during execution, for instance, when the user modifies a data row or when it is selected, the row status, among others.

For further details, see the DikeGridDataRowEntry definition.

Once the DikeGrid receives and wraps the data, it assigns and emits a unique id. You can get this id by listening to the dataDeliveryIdChange event.

Indeed, a DikeGrid instance will send a unique id every time you provide a new set of entries. It means that you can have an Observable or a DikeGridDataSource, and if you change the entries set, the DikeGrid will wrap these new entries.

Let us listen to the dataDeliveryIdChange event:

in-memory-data-source.component.html

<dike-grid id="grid-in-memory-datasource" height="650px" #grid="dkgGrid"
    (dataDeliveryIdChange)="onDataDeliveryIdChange($event)">
</dike-grid>

in-memory-data-source.component.ts

onDataDeliveryIdChange(id: string): void {
  console.log(`Data delivery id: ${id}`);
}

Open your dev console to see the emitted id.

The DikeGrid internally creates a DikeGridDataSource instance to wrap every data entry.

Be aware that every time a DikeGrid instance wraps the provided entries, it resets the edition and selection operations. It means that the DikeGrid removes the history of changes and deselects rows.

Row Ids

The DikeGrid sets a unique id number for every row during the wrapping operation. This id number is a consecutive number starting at the zero number.

You can open any live example, go to the Floating Configuration Panel, scroll to the Rows section and mark the Row Id checkbox.

Floating Configuration Panel - Rows

Row Ids

Timestamp / Row status

Other values that the DikeGrid creates and assigns to every row are the timestamp and the initial row status.

The timestamp corresponds to the row creation time and the row status to the Read value. The Read value means that the user has not modified the row.

The DikeGrid uses the row status and the timestamp properties to manage the edition operations. See the Row Edition section.