How to add data dynamically to mat-table dataSource?

Question

I have data streaming from backend and i see it printing in console now i am trying to push event to dataSource its throwing error dataSource is not defined. Ca

Answer 1

I was stuck in same problem while creating select row and apply some action over rows data. This solution for your problem

imports..................
import { MatTableDataSource } from '@angular/material';
@component({ ...

export class StreamComponent implements OnInit {
// Initialise MatTableDataSource as empty
dataSource = new MatTableDataSource();

constructor() {}
...
// if you simply push data in dataSource then indexed 0 element remain undefined
// better way to do this as follows
 this.dataSource.data = val as any;

  // for your problem

   ngOnInit() {
  // ** important note .... I am giving solution assuming the subscription data is array of objects. Like in your case stream and in second event(parameter as callback)
    this.streamService.getAllStream().subscribe(stream => {
       // do it this way
        this.dataSource.data = stream as any;
     // note if you simply put it as 'this.dataSource.data = stream' then TS show you error as '[ts] Type 'string' is not assignable to type '{}[]''
    });
    this.socket.on('newMessage', (event) => {
        console.log('Datasource', event);
          // for this value
       // this.dataSource.MatTableDataSource.filteredData.push(event);   // I couldn't get what you are doing here 
     // SO try to explain what you are getting in this callback function val as event parameter ????????????????? 
     // but you can get it this ways

       this.dataSource.filteredData = event as any;
    });
  }

Hope this will help you . If you have any question just ping me.