How to set a default value for AngularJS ng-repeat? - angularjs

Question

<li ng-repeat="item in quantityList track by $index" ng-model="isPageValid='true'">
<input value="item.quantity" ng-blur="validateQuantity(item)" ng-model="item.quantity">
</li>
I'm trying to set a default value for a status variable each time an ng-repeat loop occurs. I've tried ng-model, but that doesn't work. For instance,
I'd like to set isPageValid="true" before each time the ng-repeat loop runs. 'True' is will be the default value, and the validation function will test whether isPageValid should be set to 'false'.
I'd like the ng-repeat loop to run each time the ng-blur is exercised.
NOTE: I understand the way I'm using ng-model is incorrect, but this is just to illustrate the issue.
HTML:
<li ng-repeat="item in quantityList track by $index" ng-model="isPageValid='true'">
<input value="item.quantity" ng-blur="validateQuantity(item)" ng-model="item.quantity">
</li>
JS:
scope.validateQuantity = function(item){
var qty = item.quantity;
if(parseInt(qty) >=1 && parseInt(qty) <= 200){
item.isQuantityValid = true;
}else{
item.isQuantityValid = false;
scope.isPageValid = false;
}
}
The loop creates a list of input boxes. The objective is to create a global validation value called isPageValid which is 'false' if the validation by the JS fails for any input box. Note, when ng-blur is exercised, the JS validation runs and loop should re-run.

Answer 1

I believe ng-init could help...
<ul ng-init="isPageValid='true'">
<li ng-repeat="item in quantityList track by $index" >
<input ng-blur="validateQuantity(item)" ng-model="item.quantity">
</li>
</ul>
Note that it would be better practice to initialise isPageValid in the controller that is in the same scope as your validateQuantity function.

Answer 2

Here is an example of how you could initialise isPageValid in your controller and update the value after each call to validateQuantity...
In your controller:
scope.isPageValid = true;
function updatePageValid() {
scope.isPageValid = scope.quantityList.every(item => item.isQuantityValid);
}
scope.validateQuantity = function(item) {
var qty = parseInt(item.quantity);
item.isQuantityValid = (qty >= 1 && qty <= 200);
updatePageValid();
});