"No Row To Show" message is coming after data binding from Services - ag-grid

Question

The "No Row To Show" message is showing in grid, but the grid one row of data.
I have a demoComponent.ts and html file.
please refer my below code
demoComponent.ts
import { GridOptions } from "ag-grid/main";
import { Service } from '../Services/service';
#Component({
.
templateUrl: 'demoComponent.html',
.
})
#Injectable()
export class demoComponent implements OnInit {
GridOptions: GridOptions;
GridColumnDefs: any[];
GridData: any[];
data1 : any[]
constructor(private Service: Servicee) {
}
ngOnInit() {
this.GridOptions = <GridOptions>{
enableFilter: false,
rowSelection: 'multiple',
enableSorting: true,
enableColResize: true,
singleClickEdit: true,
animateRows: true,
headerHeight: 50,
rowClass: 'rowClass'
};
Observable.forkJoin(
this.Service.methed1(this.id),
this.Service.methed1(this.id),
this.Service.methed1(this.id),
this.Service.methed1()
).subscribe(response => {
this.data1 = <any>response[0];
this.data2 = <any>response[1];
this.data3 = <any>response[2];
this.data4 = <any>response[3];
this.GridBind()
});
}
GridBind()
{
this.GridColumnDefs = [
{ headerName: "", field: "id", hide: true },
{ headerName: "Column1", field: "Column1", width: 70, editable: true, tooltipField: "release", headerTooltip: "Release" },
{ headerName: "Column2", field: "Column2", width: 80, editable: true, tooltipField: "Column2", headerTooltip: "Column2",
//cellEditorFramework: EstimatingSourceComponent
cellEditorFramework: EstimatingSourceComponent,
cellEditorParams: {
dropDownValue: this.data1,
}
},
{ headerName: "Column3", field: "Column3", width: 70, editable: true },
{ headerName: "Column4", field: "Column4", width: 70, editable: true },
];
this.GridData = [
{
id: 1, Column1: this.data1.value1, Column2: this.data1.value2, Column3: this.data1.value3, Column4: this.data1.value4
}
];
}
}
Then the demoComponent.html
<ag-grid-angular style="width: 100%; height: 350px;"
id="grid1"
class="ag-fresh"
[rowData]="GridData"
[columnDefs]="GridColumnDefs"
[gridOptions]="GridOptions">
</ag-grid-angular>
on rendering the one row is binded with the grid. but "No Row To Show" is showing.
Please correct my implementation , if it is wrong.
thanks in advance