How to disable multiple textboxes in angular 2

I have 'n' number of rows which has textbox and select box. I am trying to disable a textbox when i change the value of a select box in the same row using angular 2.

My code is below:

<table>
  <tr>
    <td><input type="text" (disabled)="isDisabled(data.rowIndex)"</td>
    <td> <select (onValueChanged)="test(data.rowIndex)">
           <option>Yes</option>
           <option>No</option>
    </td>
   </tr>
   <tr>
    <td><input type="text" (disabled)="isDisabled(data.rowIndex)"</td>
    <td> <select (onValueChanged)="test(data.rowIndex)">
           <option>Yes</option>
           <option>No</option>
    </td>
   </tr>
   .
   .
   .
</table>

component.ts

tabNumber: number = -1;

test(valueID){
        this.tabNumber = valueID;
}

isDisabled(num){
        return this.tabNumber === num;
    }

This above line disables only one textbox which i selected recently and enables other textboxes. Thus, my code could enable/disable only one textbox at a time. But i want to disable multiple boxes based on my selection. can anybody help?

see it in action on : plunker

html :

<table>
   <tr *ngFor="let item of items; let i = index">
    <td><input type="text" [disabled]="isDisabled(i)"/></td>
    <td> <select (change)="toggle($event,i)">
           <option value="yes">Yes</option>
           <option value="no">No</option>
          </select>
    </td>
   </tr>

</table>

component:

export class AppComponent {
   items = [{value : "hi"},{value : "hi"},{value : "hi"},{value : "hi"}]
   rows: number[] = [];

  isDisabled(index) {
    return this.rows[index] === -1;
  }

  enable(index){
    this.rows[index] = 1;
  }

  toggle($event,index){
    let selectElement = $event.target; 
    let value = selectElement.options[selectElement.selectedIndex].value;
    if(value === "yes"){
       this.enable(index);
    }else{
       this.disable(index);
    }
  }

  disable(index){
    this.rows[index] = -1;
  }
}