Checkbox not binding to ng-model inside ng-repeat

I am rendering my DataTable the angular way, I added a select all checkbox at the top and per row I added a checkbox and number textbox.

If the checkbox per row is checked then the number textbox would be enabled.

The problem is that for example, I check selectAll then the checkbox per row would be checked but the number textbox remains disabled. I checked the value of the checkbox per row and it was false even though the checkbox was checked.

see plunker.

Source: AngularJS