Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

how to access parent component scope from a child components scope in ember?

I'm curious if this is even possible in ember. This is an easy thing to do in angular ( plunkr: http://plnkr.co/edit/O2e0ukyXdKMs4FcgKGmX?p=preview ):

The goal is to make an easy to use, generic, reusable accordion api for api consumers.

The api I want the caller to be able to use is this (just like the angular api):

{{#ember-accordion listOfAccordionPaneObjects=model}}

  {{#ember-accordion-heading}}
     heading template html {{accordionPaneObject.firstName}}
  {{/ember-accordion-heading}}

  {{#ember-accordion-body}}
     this is the accordion body  {{accordionPaneObject.lastName}}
  {{/ember-accordion-body}}

{{/ember-accordion}}

Here is a working example I wrote using angular:

<!doctype html>
<html ng-app="angular-accordion">
<head>
    <style>
        .angular-accordion-header {
            background-color: #999;
            color: #ffffff;
            padding: 10px;
            margin: 0;
            line-height: 14px;
            -webkit-border-top-left-radius: 5px;
            -webkit-border-top-right-radius: 5px;
            -moz-border-radius-topleft: 5px;
            -moz-border-radius-topright: 5px;
            border-top-left-radius: 5px;
            border-top-right-radius: 5px;
            cursor: pointer;
            text-decoration: none;
            font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
            font-size: 14px;
        }

        .angular-accordion-container {
            height: 100%;
            width: 100%;
        }

        .angular-accordion-pane {
            padding: 2px;
        }

        .angularaccordionheaderselected {
            background-color: #bbb;
            color: #333;
            font-weight: bold;
        }

        .angular-accordion-header:hover {
            text-decoration: underline !important;
        }

        .angularaccordionheaderselected:hover {
            text-decoration: underline !important;
        }

        .angular-accordion-pane-content {
            padding: 5px;
            overflow-y: auto;
            border-left: 1px solid #bbb;
            border-right: 1px solid #bbb;
            border-bottom: 1px solid #bbb;
            -webkit-border-bottom-left-radius: 5px;
            -webkit-border-bottom-right-radius: 5px;
            -moz-border-radius-bottomleft: 5px;
            -moz-border-radius-bottomright: 5px;
            border-bottom-left-radius: 5px;
            border-bottom-right-radius: 5px;
        }

        .angulardisabledpane {
            opacity: .2;
        }
    </style>
</head>
<body style="margin: 0;">


<div style="height: 90%; width: 100%; margin: 0;" ng-controller="outerController">

    <angular-accordion list-of-accordion-pane-objects="outerControllerData">
        <pane>
            <pane-header>Header {{accordionPaneObject}}</pane-header>
            <pane-content>Content {{accordionPaneObject}}</pane-content>
        </pane>
    </angular-accordion>

</div>

    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.1/angular.js"></script>
    <script>
        angular.module('angular-accordion', [])
                .directive('angularAccordion', function() {
                    var template = '';

                    return {
                        restrict: 'E',
                        transclude: true,
                        replace: true,
                        template: '<div>' +
                                        '<div ng-transclude class="angular-accordion-container" ng-repeat="accordionPaneObject in listOfAccordionPaneObjects"></div>' +
                                  '</div>',
                        controller: ['$scope', function($scope) {
                            var panes = [];

                            this.addPane = function(pane) {
                                panes.push(pane);
                            };
                        }],
                        scope: {
                            listOfAccordionPaneObjects: '='
                        }
                    };
                })
                .directive('pane', function() {
                    return {
                        restrict: 'E',
                        transclude: true,
                        replace: true,
                        template: '<div ng-transclude class="angular-accordion-pane"></div>'
                    };
                })
                .directive('paneHeader', function() {
                    return {
                        restrict: 'E',
                        require: '^angularAccordion',
                        transclude: true,
                        replace: true,
                        link: function(scope, iElement, iAttrs, controller) {
                            controller.addPane(scope);

                            scope.toggle = function() {
                                scope.expanded = !scope.expanded;
                            };
                        },
                        template: '<div ng-transclude class="angular-accordion-header" ng-click="toggle()"></div>'
                    };
                })
                .directive('paneContent', function() {
                    return {
                        restrict: 'EA',
                        require: '^paneHeader',
                        transclude: true,
                        replace: true,
                        template: '<div ng-transclude class="angular-accordion-pane-content" ng-show="expanded"></div>'
                    };
                })
                .controller('outerController', ['$scope', function($scope) {
                    $scope.outerControllerData = [1, 2, 3];
                }]);
    </script>
</body>
</html>

here's where I'm stuck doing the same with ember:

index.html

<!DOCTYPE html>
<html>
    <body>
        <script src="//cdnjs.cloudflare.com/ajax/libs/require.js/2.1.9/require.js" data-main="main.js"></script>
    </body>
</html>

main.js

require.config({
    paths: {
        'ember': 'bower_components/ember/ember',
        'handlebars': 'bower_components/handlebars/handlebars',
        'jquery': 'bower_components/jquery/jquery',
        'text': 'bower_components/requirejs-text/text'
    },
    shim: {
        ember: {
            deps: ['jquery', 'handlebars'],
            exports: 'Ember'
        }
    }
});

define(function(require) {
    var Ember = require('ember'),
        EmberAccordionComponent = require('src/EmberAccordionComponent'),
        EmberAccordionTemplate = require('text!templates/ember-accordion.hbs'),
        EmberAccordionHeaderTemplate = require('text!templates/ember-accordion-header.hbs'),
        EmberAccordionBodyTemplate = require('text!templates/ember-accordion-body.hbs'),
        ApplicationTemplate = require('text!templates/application.hbs'),
        IndexTemplate = require('text!templates/index.hbs');

    var App = Ember.Application.create({
        LOG_STACKTRACE_ON_DEPRECATION : true,
        LOG_BINDINGS                  : true,
        LOG_TRANSITIONS               : true,
        LOG_TRANSITIONS_INTERNAL      : true,
        LOG_VIEW_LOOKUPS              : true,
        LOG_ACTIVE_GENERATION         : true
    });

    Ember.TEMPLATES = {};
    Ember.TEMPLATES['application'] = Ember.Handlebars.compile(ApplicationTemplate);
    Ember.TEMPLATES['index'] = Ember.Handlebars.compile(IndexTemplate);
    Ember.TEMPLATES['components/ember-accordion'] = Ember.Handlebars.compile(EmberAccordionTemplate);
    Ember.TEMPLATES['components/ember-accordion-header'] = Ember.Handlebars.compile(EmberAccordionHeaderTemplate);
    Ember.TEMPLATES['components/ember-accordion-body'] = Ember.Handlebars.compile(EmberAccordionBodyTemplate);

    App.EmberAccordionComponent = EmberAccordionComponent;

    App.IndexRoute = Ember.Route.extend({
        model: function() {
            return [
                {
                    name: 'Bob'
                },
                {
                    name: 'Jill'
                }]
        }
    })
});

EmberAccordionComponent.js

define(function(require) {
    require('ember');

    var EmberAccordionComponent = Ember.Component.extend({});

    return EmberAccordionComponent;
});

application.hbs

{{outlet}}

ember-accordion-header.hbs

<div style="color: blue;">
    {{yield}}
</div>

ember-accordion-body.hbs

<div style="color: green;">
    {{yield}}
</div>

index.hbs

{{#ember-accordion listOfAccordionPaneObjects=model}}
    {{#ember-accordion-header}}
        {{log this.constructor}}
        {{log this}}
        Header {{accordionPaneObject.name}}
    {{/ember-accordion-header}}
    {{#ember-accordion-body}}
        Body {{accordionPaneObject.name}}
    {{/ember-accordion-body}}
{{/ember-accordion}}

ember-accordion.hbs

{{#each accordionPaneObject in listOfAccordionPaneObjects}}
    {{yield}}
{{/each}}

--

This is tricky to debug. So putting in the:

{{log this.constructor}}

and the:

{{log this}}

into the:

{{#ember-accordion-header}}

outputs the following:

  • Class.model = undefined (why?)
  • Ember.ArrayController

I've tried overriding the private _yield method of Ember.Component as suggested by this article ( http://www.thesoftwaresimpleton.com/blog/2013/11/21/component-block/ ):

var EmberAccordionHeaderComponent = Ember.Component.extend({
    _yield: function(context, options) {
        var get = Ember.get,
            view = options.data.view,
            parentView = this._parentView,
            template = get(this, 'template');

        if (template) {
            Ember.assert("A Component must have a parent view in order to yield.", parentView);
            view.appendChild(Ember.View, {
                isVirtual: true,
                tagName: '',
                _contextView: parentView,
                template: template,
                context: get(view, 'context'), // the default is get(parentView, 'context'),
                controller: get(view, 'controller'), // the default is get(parentView, 'context'),
                templateData: { keywords: parentView.cloneKeywords() }
            });
        }
    }
});

but when I do this I still don't have access to accordionPaneObject in my child component scope, and my {{log this.constructor}} now points to: .EmberAccordionHeaderComponent

So it looks like I'm getting somewhere, I just need to go one more level up.

When I try that using this code in EmberAccordionHeaderComponent.js:

var EmberAccordionHeaderComponent = Ember.Component.extend({
    _yield: function(context, options) {
        var get = Ember.get,
            view = options.data.view,
            parentView = this._parentView,
            grandParentView = this._parentView._parentView,
            template = get(this, 'template');

        if (template) {
            Ember.assert("A Component must have a parent view in order to yield.", parentView);
            view.appendChild(Ember.View, {
                isVirtual: true,
                tagName: '',
                _contextView: parentView,
                template: template,
                context: get(grandParentView, 'context'), // the default is get(parentView, 'context'),
                controller: get(grandParentView, 'controller'), // the default is get(parentView, 'context'),
                templateData: { keywords: parentView.cloneKeywords() }
            });
        }
    }
});

I still don't access to accordionPaneObject in, but now I see {{log this.constructor}} outputting .EmberAccordionComponent. So it appears I'm in the right scope, but the data still doesn't bind.

Interestingly enough, if I use any of these variations of reassigning context and controller in my overridden _yield, I can access the data I am after in the console using:

this._parentView._context.content
like image 925
davidjnelson Avatar asked Nov 23 '13 05:11

davidjnelson


People also ask

What is glimmer component?

args within Glimmer components, which is an immutable object. This means that: It's clear when you are accessing arguments passed to the component, and when you are accessing fields and properties of the component itself.

What is parent and child component in angular?

concept parent component in category angularA parent component can pass data to its child by binding the values to the child's component property. A child component has no knowledge of where the data came from. A child component can pass data to its parent (without knowing who the parent is) by emitting events.


1 Answers

I updated your code with some comments please give a look http://emberjs.jsbin.com/ivOyiZa/1/edit.

Javascript

App = Ember.Application.create();

App.IndexRoute = Ember.Route.extend({
  model: function() {
    return [
      { head: "foo head", body: "foo body " },
      { head: "bar head", body: "bar body " },
      { head: "ya head", body: "yo body " }
    ];
  }
});

App.EmberAccordionComponent = Ember.Component.extend({
  // each accordion header/body item, will have a instance of that view.
  // so we can isolate the expanded state for each accordion header/body
  emberAccordionItemView: Ember.View.extend({    
    expanded: false
  }),
  _yield: function(context, options) {
    var get = Ember.get, 
    view = options.data.view,
    parentView = this._parentView,
    template = get(this, 'template');

    if (template) {
      Ember.assert("A Component must have a parent view in order to yield.", parentView);      
      view.appendChild(Ember.View, {
        isVirtual: true,
        tagName: '',
        _contextView: parentView,
        template: template,
        context: get(view, 'context'), // the default is get(parentView, 'context'),
        controller: get(view, 'controller'), // the default is get(parentView, 'context'),
        templateData: { keywords: parentView.cloneKeywords() }
      });
    }
  }
});

App.EmberAccordionHeaderComponent = Ember.Component.extend({  
  classNames: ['ember-accordion-header'],  
  click: function() {
    // here we toggle the emberAccordionItemView.expanded property
    this.toggleProperty('parentView.expanded');  
  }
});

Templates

  <script type="text/x-handlebars" data-template-name="index">
    {{#ember-accordion listOfAccordionPaneObjects=model}}                        
          {{#ember-accordion-header}}
              {{head}} <!-- each object passed in listOfAccordionPaneObjects=model can be accessed here -->
          {{/ember-accordion-header}}
          {{#ember-accordion-body}}
              {{body}} <!-- each object passed in listOfAccordionPaneObjects=model can be accessed here -->
          {{/ember-accordion-body}}        
    {{/ember-accordion}}        
  </script>

  <script type="text/x-handlebars" data-template-name="components/ember-accordion">     
    {{#each listOfAccordionPaneObjects itemViewClass="view.emberAccordionItemView"}}            
      <div class="ember-accordion-container">
        <div class="ember-accordion-pane">          
            {{yield}}          
        </div>
      </div>      
    {{/each}}
  </script>

  <script type="text/x-handlebars" data-template-name="components/ember-accordion-header">        
    {{yield}}    
  </script>

  <script type="text/x-handlebars" data-template-name="components/ember-accordion-body">    
    <!-- when EmberAccordionHeaderComponent.click is called, the expanded property change and the content can be visible or not, based on expanded truth -->
    {{#if parentView.expanded}}
      <div class="ember-accordion-pane-content">
        {{yield}}
      </div>
    {{/if}}
  </script>

Css

.ember-accordion-header {
  background-color: #999;
  color: #ffffff;
  padding: 10px;
  margin: 0;
  line-height: 14px;
  -webkit-border-top-left-radius: 5px;
  -webkit-border-top-right-radius: 5px;
  -moz-border-radius-topleft: 5px;
  -moz-border-radius-topright: 5px;
  border-top-left-radius: 5px;
  border-top-right-radius: 5px;
  cursor: pointer;
  text-decoration: none;
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 14px;
}

.ember-accordion-container {
  height: 100%;
  width: 100%;
}

.ember-accordion-pane {
  padding: 2px;
}

.emberaccordionheaderselected {
  background-color: #bbb;
  color: #333;
  font-weight: bold;
}

.ember-accordion-header:hover {
  text-decoration: underline !important;
}

.emberaccordionheaderselected:hover {
  text-decoration: underline !important;
}

.ember-accordion-pane-content {
  padding: 5px;
  overflow-y: auto;
  border-left: 1px solid #bbb;
  border-right: 1px solid #bbb;
  border-bottom: 1px solid #bbb;
  -webkit-border-bottom-left-radius: 5px;
  -webkit-border-bottom-right-radius: 5px;
  -moz-border-radius-bottomleft: 5px;
  -moz-border-radius-bottomright: 5px;
  border-bottom-left-radius: 5px;
  border-bottom-right-radius: 5px;
}

.emberdisabledpane {
  opacity: .2;
}
like image 193
Marcio Junior Avatar answered Oct 11 '22 10:10

Marcio Junior