ng2-smart-table with paging from back-end (Spring)

Question

I am using a back-end server (Java Spring) that has Pager enabled. I am loading 100 records per page on a HTTP call.

On angular2 service, it is consuming the API ca

Answer 1

I solved this problem with LocalDataSource.

HTML:

<ng2-smart-table [settings]="settings" [source]="source"></ng2-smart-table>

TS:

source: LocalDataSource = new LocalDataSource();
pageSize = 25;

ngOnInit() {
  this.source.onChanged().subscribe((change) => {
    if (change.action === 'page') {
      this.pageChange(change.paging.page);
    }
  });
}

pageChange(pageIndex) {
  const loadedRecordCount = this.source.count();
  const lastRequestedRecordIndex = pageIndex * this.pageSize;

  if (loadedRecordCount <= lastRequestedRecordIndex) {    
    let myFilter; //This is your filter.
    myFilter.startIndex = loadedRecordCount + 1;
    myFilter.recordCount = this.pageSize + 100; //extra 100 records improves UX.

    this.myService.getData(myFilter) //.toPromise()
      .then(data => {
        if (this.source.count() > 0){
          data.forEach(d => this.source.add(d));
          this.source.getAll()
          .then(d => this.source.load(d))
      }
        else
          this.source.load(data);
      })
  }
}

Answer 2

Also if you need to customize request to back-end there is configuration parameters for ServerDataSource that is used for data retrieving/pagination/sorting.

Answer 3

When you have your endpoint for some entity on {endPointBase}/ng2-smart-table, where you are processing key_like request params (i.e: @Requestparam Map to spring data Example) , you can use on client side:

export class SpringDataSource extends ServerDataSource {
    constructor(http: HttpClient, endPointBase: string) {
        const serverSourceConf = new ServerSourceConf();
        serverSourceConf.dataKey = 'content';
        serverSourceConf.endPoint = endPointBase + `/ng2-smart-table`;
        serverSourceConf.pagerLimitKey = 'size';
        serverSourceConf.pagerPageKey = 'page';
        serverSourceConf.sortFieldKey = 'sort';
        serverSourceConf.totalKey = 'totalElements';

        super(http, serverSourceConf);
    }

    protected addPagerRequestParams(httpParams: HttpParams): HttpParams {
        const paging = this.getPaging();
        return httpParams
            .set(this.conf.pagerPageKey, (paging.page - 1).toString())
            .set(this.conf.pagerLimitKey, paging.perPage.toString());
    }

    protected addSortRequestParams(httpParams: HttpParams): HttpParams {
        const sort: {field: string, direction: string}[] = this.getSort();

        sort.forEach((column) => {
            httpParams = httpParams.append(this.conf.sortFieldKey, `${column.field},${column.direction}`);
        });
        return httpParams;
    }
}

Answer 4

Try to set the settings to the smart-table like this

<ng2-smart-table #grid [settings]="settings" ... >

And at your component, define the settings, something like this:

  public settings: TableSettings = new TableSettings();

  ngOnInit(): void {
      ...
    this.settings.pager.display = true;
    this.settings.pager.perPage = 100;
    ...
  }