What is the idiomatic way of communicating between Onsen popover and its parent?

Question

This is what I've got so far. First the script:

ons.bootstrap();
.controller('AppController', function($scope) {
  $scope.greeting = "Hello!";
  ons.createPopover('popover.html').then(function(popover) {
    $scope.popover = popover;
    popover.on('preshow', function() {
      popover._scope.greeting = $scope.greeting;
    });
    popover.on('posthide', function() {
      $scope.greeting = popover._scope.greeting;
      $scope.$apply();
    });
  });
});

And the page:

<ons-page ng-controller="AppController">
  <ons-toolbar>
    <div class="center">Popover</div>
  </ons-toolbar>

  <div style="margin-top: 100px; text-align: center">
    <ons-button modifier="light" ng-click="popover.show($event)">Show popover</ons-button>
  </div>
  <div style="margin-top: 100px; text-align: center">{{greeting}}</div>

</ons-page>

<ons-template id="popover.html">
  <ons-popover direction="up down" cancelable>
    <div style="text-align: center; opacity: 0.8;">
      <input style="margin: 20px" type="text" ng-model="greeting" />
    </div>
  </ons-popover>
</ons-template>

This seems to work for me, but I'm not sure about the popover._scope part. Is it supposed to be accessed like that? I can't seem to find any other way.

So what is the idiomatic way to do this? And what are some good examples?

Thank you.

Answer 1

You can use the parentScope parameter to make the popover scope a descendant of the AppController scope:

module.controller('AppController', function($scope) {
  ons.createPopover('popover.html', {parentScope: $scope});
});

Now you have some options on how to communicate between the scopes. Since the popover scope is a descendant of the AppController scope you can for instance use $scope.$emit() to emit events when the value changes:

module.controller('AppController', function($scope) {
  $scope.greeting = 'Hello!';

  ons.createPopover('popover.html', {parentScope: $scope}).then(function(popover) {
    $scope.popover = popover;
  });

  $scope.$on('update', function(event, value) {
    $scope.greeting = value;
  });
})

.controller('PopoverController', function($scope) {
  $scope.$watch('greeting', function(value) {
    $scope.$emit('update', value);
  });
});

I made a simple example: http://codepen.io/argelius/pen/avmqOP

You can also use ngModel to access the the value but keep in mind that it's actually the grandparent so in that case you need to do ng-model="$parent.$parent.greeting" which is not very nice.

I would recommend the event approach.