Data binding in JavaScript Kanban control

18 Nov 20187 minutes to read

The Kanban uses DataManager, which supports both RESTful data service binding and JavaScript object array binding. The dataSource property of Kanban can be assigned either with the instance of DataManager or JavaScript object array collection, as it supports the following two data binding methods:

• Local data
• Remote data

Local data

To bind local JSON data to the Kanban, you can simply assign a JavaScript object array to the dataSource property. The JSON object dataSource can also be provided as an instance of DataManager and assigned to the Kanban dataSource property.

By default, DataManager uses JsonAdaptor for binding local data.

Remote data

To bind remote data to kanban component, assign service data as an instance of DataManager to the dataSource property. To interact with remote data source, provide the endpoint url.

By default, DataManager uses ODataAdaptor for remote data-binding.

OData services

OData is a standardized protocol for creating and consuming data. You can retrieve data from OData service using the DataManager. Refer to the following code example for remote Data binding using OData service.

OData v4 services

The ODataV4 is an improved version of OData protocols, and the DataManager can also retrieve and consume OData v4 services. For more details on OData v4 services, refer to the odata documentation. To bind OData v4 service, use the ODataV4Adaptor.

Web API

You can use WebApiAdaptor to bind kanban with Web API created using OData endpoint.

import { Kanban } from '@syncfusion/ej2-kanban';
import { DataManager, WebApiAdaptor  } from '@syncfusion/ej2-data';

let data: DataManager = new DataManager({
    url: '/api/Tasks',
    adaptor: new WebApiAdaptor
});
let kanbanObj: Kanban = new Kanban({
    dataSource: data,
    keyField: 'Status',
    columns: [
        { headerText: 'Backlog', keyField: 'Open' },
        { headerText: 'In Progress', keyField: 'InProgress' },
        { headerText: 'Testing', keyField: 'Testing' },
        { headerText: 'Done', keyField: 'Close' }
    ],
    cardSettings: {
        contentField: 'Summary',
        headerField: 'Id'
    },
    allowDragAndDrop: false,
    dialogOpen: dialogOpen
});
kanbanObj.appendTo('#Kanban');
function dialogOpen(args: DialogEventArgs): void {
    args.cancel = true;
}

Below server-side controller code to get the Kanban data.

[HttpGet]
        public object Get()
        {
            var data = OrdersDetails.GetAllRecords().ToList();
            return data;
        }

URL adaptor

The CRUD (Create, Read, Update and Delete) actions can be performed easily on Kanban cards using the various adaptors available within the DataManager. Most preferably, we will be using UrlAdaptor for performing CRUD actions on Kanban.

The CRUD operation in Kanban can be mapped to server-side controller actions using the properties insertUrl, removeUrl, updateUrl, and crudUrl.

• insertUrl – You can perform a single insertion operation on the server-side.
• updateUrl – You can update single data on the server-side.
• removeUrl – You can remove single data on the server-side.
• crudUrl – You can perform bulk data operation on the server-side.

import { Kanban } from '@syncfusion/ej2-kanban';
import { DataManager, UrlAdaptor } from '@syncfusion/ej2-data';

let data: DataManager = new DataManager({
    url: 'Home/DataSource',
    updateUrl: 'Home/Update',
    insertUrl: 'Home/Insert',
    removeUrl: 'Home/Delete',
    adaptor: new UrlAdaptor(),
    crossDomain: true
});
let kanbanObj: Kanban = new Kanban({
    dataSource: data,
    keyField: 'Status',
    columns: [
        { headerText: 'Backlog', keyField: 'Open' },
        { headerText: 'In Progress', keyField: 'InProgress' },
        { headerText: 'Testing', keyField: 'Testing' },
        { headerText: 'Done', keyField: 'Close' }
    ],
    cardSettings: {
        contentField: 'Summary',
        headerField: 'Id'
    }
});
kanbanObj.appendTo('#Kanban');

The server-side controller code to handle the CRUD operations are as follows.

private NORTHWNDEntities db = new NORTHWNDEntities();
public ActionResult DataSource() {
    var DataSource = db.Tasks.ToList();
    return Json(DataSource, JsonRequestBehavior.AllowGet);
}
public ActionResult Insert(Params value) {
    //Insert card data into the database
    return Json(value, JsonRequestBehavior.AllowGet);
}
public ActionResult Update(Params value) {
    //Update card data into the database
    return Json(value, JsonRequestBehavior.AllowGet);
}
public void Delete(Params value) {
    //Delete card data from the database
}

public class Params {
    public int Id { get; set; }
    public string Status { get; set; }
    public string Summary { get; set; }
    public string Assignee { get; set; }
}

The crudUrl is used to update the bulk data sent to the server-side. Multiple selections and sortBy as Index properties are used for crudUrl properties to update the modified bulk data to the server-side.

Custom adaptor

It is possible to create your own custom adaptor by extending the built-in available adaptors. The following example demonstrates the custom adaptor usage and how to add a custom field TaskId for the cards by overriding the built-in response processing using the processResponse method of the ODataAdaptor.

Sending additional parameters to the server

To add a custom parameter to the data request, use the addParams method of Query class. Assign the Query object with additional parameters to the kanban query property.

The parameters added using the query property will be sent along with the data request for every kanban action.

Handling HTTP error

During server interaction from the kanban, some server-side exceptions may occur, and you can acquire those error messages or exception details
in client-side using the actionFailure event.

The argument passed to the actionFailure event contains the error details returned from the server.

The actionFailure event will be triggered not only for the server errors, but also when there is an exception while processing the kanban actions.

Loading data via ajax

You can use Kanban dataSource property to bind the datasource to Kanban from external ajax request. In the following code, we have fetched the datasource from the server using ajax request and provided that to the dataSource property by using the onSuccess event of ajax.

• If you bind the dataSource from this way, then it acts like a local dataSource. So you cannot perform any server-side crud actions.