Polymer - Accessing Root Element - polymer

I'm learning Polymer. I've been trying to integrate Polymer into an existing page. In an attempt to do that, I have the following:
<body>
<div class="row">
<div class="col-sm-8">
<template is="dom-bind" id="app">
<iron-signals on-iron-signal-update-greeting="_updateGreeting">
<div>[[ greeting ]]</div>
</template>
</div>
<div class="col-sm-4">
<button type="button" click="testClick();">Test</button>
</div>
</div>
<script type="text/javascript">
function testClick() {
this.fire('iron-signal', { name: 'updateGreeting', data: { value: 'Hello at ' + (new Date().getMinutes()) } });
}
</script>
</body>
This is a learning exercise regarding iron-signals. I understand how to use iron-signals within a Polymer app. However, I'm trying to fire off a signal from outside of the app. When I do this, I get the following error:
this.fire is not a function
I understand why I'm getting the error. However, I guess I don't understand how to get a reference to the actual Polymer object so that I can call the fire function.

You need to wait for Polymer to upgrade the elements. See Polymer and WebComponentsReady event
When you do this inside an element your code isn't called before Polymer is ready. Outside you have to take care yourself.

Related

AngularJS dynamic additions to page

We have this AngularJS SP application (smart-mirror) in electron browser, which has user createable extensions.
the extensions are small snippets of html that use angular directives
and use controllers and services.
to install an extension, one has to edit the main page and insert the script tags for the controller and service functions and a <div ng-include= ...> for the snippet of HTML
hardcoded this single page app works great.
but I want to add the capability to this app (opensource) to dynamically load those elements somehow...
adding the tags to the dom works, BUT are not processed correctly.
the HTML is processed before the scripts (from the inserted tags) are run, and when the ng-include inserts the HTML snippet, then controllers are not defined yet...
the body (with the extensions in hard-coded positions commented out)
<body ng-controller="MirrorCtrl" ng-cloak>
<div class="top">
<div class="top-left">
<!-- <div ng-include="'plugins/datetime/index.html'"></div>
<div ng-include="'plugins/calendar/index.html'"></div> -->
</div>
<div class="top-right">
<!-- <div ng-include="'plugins/weather/index.html'"></div>
<div ng-include="'plugins/traffic/index.html'"></div>
<div ng-include="'plugins/stock/index.html'"></div>
<div ng-include="'plugins/tvshows/index.html'"></div>
<div ng-include="'plugins/ha-display/index.html'"></div> -->
</div>
</div>
...
...
<script src="filename.service"/>
<script src= filename.controller"/>
</body>
the calendar extension html (inserted into specific div area of the page)
<ul ng-controller="Calendar" class="calendar fade" ng-show="focus == 'default'" ng-class="config.calendar.showCalendarNames ? 'show-calendar-names' : ''">
<li class="event" ng-repeat="event in calendar" ng-class="(calendar[$index - 1].label != event.label) ? 'day-marker' : ''">
<div class="event-details">
<span class="day">
<span ng-bind="event.startName"></span>
<span ng-if="event.startName != event.endName"> - <span ng-bind="event.endName"></span></span>
</span>
<div class="details calendar-name" ng-bind="event.calendarName"></div>
<span class="summary" ng-bind="event.SUMMARY"></span>
<div class="details" ng-if="event.start.format('LT') != event.end.format('LT')">
<span ng-if="event.startName != event.endName"><span ng-bind="event.start.format('M/D')"></span> <span ng-bind="event.start.format('LT')"></span> - <span ng-bind="event.end.format('M/D')"></span> <span ng-bind="event.end.format('LT')"></span></span>
<span ng-if="event.startName == event.endName"><span ng-bind="event.start.format('LT')"></span> - <span ng-bind="event.end.format('LT')"></span></span>
</div>
<div class="details" ng-if="event.start.format('LT') == event.end.format('LT')">All day</div>
</div>
</li>
</ul>
the calendar extension controller (used by the html)
function Calendar($scope, $http, $interval, CalendarService) {
var getCalendar = function(){
CalendarService.getCalendarEvents().then(function () {
$scope.calendar = CalendarService.getFutureEvents();
}, function (error) {
console.log(error);
});
}
getCalendar();
$interval(getCalendar, config.calendar.refreshInterval * 60000 || 1800000)
}
console.log("registering calendar controller")
angular.module('SmartMirror')
.controller('Calendar', Calendar);
the calendar extension service (used by the controller, shortened for this discussion)
(function () {
'use strict';
function CalendarService($window, $http, $q) {
...
...
return service;
}
console.log("registering calendar service")
angular.module('SmartMirror')
.factory('CalendarService', CalendarService);
} ());
so a user wanting to add an extension would have to create these files,
and edit the main page HTML and insert them
<div ng-include src="filename.html"></div>
in the right place and then add the
<script src="filename.service" >
and
<script src="filename.controller">
in the right place and order, service needs to be done before the controller,
as controller uses service.
anyhow, it's easy to add code to locate all the extensions and dynamically insert elements into the dom in their respective places... but...
in the hard coded, the scripts are added after the html in the body
so, I added a new script (processed when the page is loaded), which locates and inserts all the elements to support the extensions in the right places..
and then the script ends.... (last one in the hard-coded HTML) and the HTML directives are processed and boom, the dynamically added scripts have not been loaded or processed, so the controllers are not found...
I CAN create a temp HTML file with all this info in it and load THAT instead of dealing with the dynamic loading, but I think its better to resolve this
I have tried creating my own angular directive and compiling that in, but get stuck in a loop
<divinc src="filename.service"></divinc>
the inserted div is correct, as a child of the divinc directive
angular.module('SmartMirror')
.directive("divincl", ["$compile" ,function($compile){
return {
priority: 100,
terminal: true,
compile: function(scope, element, attrs) {
var html = "<div ng-include=\"" + element['incl']+ "\" onload='function(){console.log(\'html loaded\')}'></div>"
var templateGoesHere = angular.element(document.getElementById(element['id']));
templateGoesHere.html(html);
//document.body.innerHTML='';
var v= $compile(templateGoesHere);
//scope.$apply();
return function linkFn(scope) {
v(scope) // Link compiled element to scope
}
}
}
}]);
advice on how to solve this problem.. Thanks
In order to make an angularjs 1.7 application load dynamically extensions, there are 2 ways:
either use "nested angularjs applications", which is clearly an advanced use of angularjs and will require you to communicate between 2 angularjs applications, to use $scope.$apply to tell the other app to update etc..
either don't load them dynamically in the frontend, but in your backend when generating the html page which contains the application. Try to list all the extensions from the start.
I recommend you to forget the use of ng-include too, and the fact of trying to add <script></script> inside a directive of your application.
First, you need to re-understand how an angularjs application is started.
When you load your main application, you have a script in which angular.module, angular.directive, angular.value, angular.config, angular.run ... calls are made. This is the declaration step
If you declare a module MyApp and that in your html you have a DOM element with ng-app="MyApp", angularjs will automatically run angular.bootstrap() on this DOM element in order to start MyApp. The execution of the application starts here. You cannot declare anything anymore in the module MyApp.
Secondly, I think that <script></script> code inside templates is sanitized and removed by angular. Plus, even if you execute the code, since the declaration step has finished, you are not supposed to create new directives or register new services, it won't work.
A good way is that when you load your plugin, you:
Load the script of the plugin from the start, it must declare a new module like MyPlugin1.
In the directive which will contain the plugin, put the code of the link I sent you, which makes possible to insert a sub-application. In the end you will have a <div ng-app="MyPlugin1"></div> inside your directive's template
Then call angular.bootstrap on that node, which will make possible to start the sub application.
If you do this, you can run the sub application, but you didn't pass it parameters. In order to pass it parameters, you can put the code of the module MyPlugin1 inside a function, in order to have an application factory. Then use app.value('param1', parameter1) to initialize the app.
For example:
function declarePlugin1(myParam1, myParam2) {
var app = angular.module('MyPlugin1', []);
// app.directive();
app.value('myParam1', myParam1);
app.value('myParam2', myParam2);
}
And inside the directive call declarePlugin1("test", 42);, which will declare the application MyPlugin1 with the initialized values, and then angular.bootstrap to tell angularjs to start this application.
You can pass callbacks too, in order to communicate between the 2 applications.

Polymer deactivating pages when their not in view

I'm using the polymer application drawer template from the polymer cli.
I'm having some trouble with:
When you load a new page, the html element is imported; then it's code executes
When I move to another page the code for the previous page is still running.
Is there a way to destroy and create the page/element or suspend and enable?
Whats the best practice for dealing with this problem?
Have the pages implement a create and destroy method and invoke it when changing page?
Ie
oldPageElement.destroy();
newPageElement.create();
Polymer({
is: 'my-random-page',
behaviors: [MyBehaviors.CommonPageBehavior],
/**
* #override
*/
create: function() {..}
/**
* #override
*/
destroy: function() {..}
})
You actually don't need to implement anything complicated, but just use a mere dom-if.
Working prototype: http://jsbin.com/gezihatera/edit?html,console,output
As you can see, the "View One" uses a custom page element, which is always restamped when re-selected. Other pages are ordinary div elements, since this is only a minimal prototype. But this also shows that you can selectively choose which pages get restamped and which do not (if you don't always need this).
The essence is the following: as per dom-if documentation, if you set the restamp attribute to true, then the dom-if will always create and destroy your pages upon selecting/deselecting them. You can see this in the console, where I print out sample-page ready on every ready element. I also create a helper function _equals to help with comparing whether the specified page is really selected.
To sum up, let me paste the code for the app:
<dom-module id="sample-app">
<template>
<style>
:host {
display: block;
}
</style>
<iron-selector selected="{{page}}" attr-for-selected="name">
<a name="view1" href="#">View One</a>
<a name="view2" href="#">View Two</a>
<a name="view3" href="#">View Three</a>
</iron-selector>
<iron-pages role="main" selected="[[page]]" attr-for-selected="name">
<template is="dom-if" if="[[_equals(page, 'view1')]]" restamp="true">
<sample-page name="view1">view1</sample-page>
</template>
<div name="view2">view2</div>
<div name="view3">view3</div>
</iron-pages>
</template>
<script>
Polymer({
is: 'sample-app',
_equals: function(a, b) {
return a == b;
},
});
</script>
</dom-module>
And the code for the sample page:
<dom-module id="sample-page">
<template>
<style>
:host {
display: block;
}
</style>
<content></content>
</template>
<script>
Polymer({
is: 'sample-page',
ready: function() {
console.log('sample-page ready');
},
});
</script>
</dom-module>
Hope this satisfies your question.
Note: you should not put the name attribute on the dom-if itself, but rather onto its content (the same way I did).
Thought I would post my solution after implementing #alesc's dom-if to get the element to be deactivated.
// after a successful importHref, _pageLoaded is called.
_pageLoaded: function(pageName) {
var name = 'my-' + pageName;
this.async(function() {
// async to wait for element restamping, if done
var pages = this.$.pages;
var page = pages.querySelector(name);
page.load()
.then(page.isAuthorized.bind(this))
.catch(this._catchPageIsAuthorizedError.bind(this))
.then(this._shouldSetPage.bind(this, pageName));
}.bind(this));
}

Polymer 1.0 strange behaviour on properties

I'm just learning polymer (1.0) so please bear with me.
I'm using express.js to return some array of JSON.stringified items and for-each them, so the result is as follows (in HTML):
<fighter-profile fighter="{"country":"USA","countryFullName":"United States","name":"Frank Mir","nickname":"","zuffa_record":{"wins":"15","losses":"9","draws":0,"no_contest":0}}"></fighter-profile>
it seems ugly as hell, but that's json.
Here's my component:
<dom-module id="fighter-profile">
<template>
<div>
<paper-item>
<paper-item-body two-line>
<div>{{fighter.name}}</div>
<div secondary>{{nickname}}</div>
<div>
<paper-button raised on-click="handleClick">Show nickname</paper-button>
</div>
</paper-item-body>
</paper-item>
</div>
<br />
<hr />
<br />
</template>
<script>
Polymer({
is: 'fighter-profile',
properties: {
fighter: Object,
nickname: {
type: String,
value: 'testing'
}
},
ready: function() {
this.nickname = (this.fighter.nickname !== '') ? this.fighter.nickname : '... the dude has no nickname!';
},
handleClick: function() {
alert(this.nickname);
}
});
</script>
</dom-module>
Now, the funny part: the name gets displayed properly, while where I have the <div secondary>{{nickname}}</div>, the result in HTML is literally {{nickname}}; however, if I click on button, I get the correct value.
What am I missing here?
UPDATE:
I've googled some stuff, and replaced ready method with created and, of course, it didn't work, since created I think is part of Polymer 0.5 version. Then I switched back to ready method and now everything works as expected. Very odd.
What seems to be the problem? Some caching gone wrong? a bug?
UPDATE 2:
I've changed some stuff again and it doesn't work, but now I've figured out how to replicate the mistake. So, this piece of code DOESN'T work correctly:
<div secondary>The dude is also known as {{nickname}}</div>
the result is literally "{{nickname}}"
However, this works correctly:
<div secondary>The dude is also known as <span>{{nickname}}</span></div>
the result is the actual nickname.
So, putting properties in span tag renders it correctly. What's going on?
There's a few things I think I can help you with here. First, you can make your JSON much more readable by using single quotes for your attributes. Additionally, you can include white space, if you are hard-coding the JSON:
<fighter-profile
fighter='{
"country":"USA",
"countryFullName":"United States",
"name":"Frank Mir",
"nickname":"",
"zuffa_record":{
"wins":"15",
"losses":"9",
"draws":0,
"no_contest":0
}
}'></fighter-profile>
Next, I'm going to assume that the JSON is actually not hard-coded, and bound to another data source. I make this assumption because it seems like your fighter property is not available in ready, as you are expecting it to be. A common issue I see in cases such as this is something like the following:
<template is="dom-repeat" items="{{data}}" as="fighter">
<fighter-profile fighter="{{fighter}}"></fighter-profile>
</template>
The thing to keep in mind in the above case is that <fighter-profile> is created, readied, and attached to the DOM before the parent element assigns fighter to its fighter property.
To remedy this, you can make use of observers which perform tasks automatically when the data gets loaded into a property:
<script>
Polymer({
is: 'fighter-profile',
properties: {
fighter: Object,
nickname: {
type: String,
value: 'testing'
}
},
observers: [
// This tells Polymer to watch `fighter` and fire the
// _fighterUpdated method only after `fighter` receives
// a value **other than undefined.**
'_fighterUpdated(fighter)'
],
_fighterUpdated: function(fighter) {
this.nickname = (this.fighter.nickname || '... the dude has no nickname!');
}
});
</script>
Next, binding properties to HTML. When you bind to HTML contents, such as with <div>{{property}}</div>, what Polymer (currently) does behind the scenes is bind property directly to div.innerText. Polymer also only checks the first two characters of innerText to see if it's a {{ or [[, and does not do anything if it doesn't find them.
The Polymer team is working to make binding more robust, but so far as I know they haven't announced any concrete plans or timelines. For the time being, the solution is as you've discovered, just wrap an inline binding in <span> =)

Data binding between published properties of two custom elements inside an auto binding template - Polymer 1.0

Problem: I have an auto binding template in my main index.html page. Inside the template I am using two of my custom elements. One element is the producer of some data and the other one is the consumer of that data. These custom elements expose published/declared properties for each other to use and bind to. I was able to do that in Polymer 0.5 fairly easily (an example shown below). How do I do the same in Polymer 1.0?
How I used to do in Polymer 0.5?
In Polymer 0.5 I used to data bind between published properties of two custom elements using curly brace syntax and then inside it used the auto node finding concept to directly bind to other element's published property. An example shown below,
<template is="auto-binding">
<my-navigation selectedLabel="Home" id="my_navigation"></my-navigation>
<my-scaffold toolbartitle="{{ $.my_navigation.selectedLabel }}" id="my_scaffold"></my-scaffold>
</template>
I tried something similar in Polymer 1.0 as shown in the example below
<template is="dom-bind">
<my-navigation selectedLabel="Home" id="my_navigation"></my-navigation>
<my-scaffold toolbartitle="{{ $.my_navigation.selectedLabel }}" id="my_scaffold"></my-scaffold>
</template>
But it throws an error:-
Uncaught TypeError: Cannot read property '$' of undefined
You can't do $.* bindings inside the template in Polymer 1.0. Instead, either refactor or use computed functions.
In your situation, since selectedLabel and toolbartitle shares the same value, it is much better to simply bind them to the same property.
Also, attribute names that are declaratively passed in (through the element tag) need to be serialized, so selectedLabel becomes selected-label.
<body>
...
<template id="tpl" is="dom-bind">
<my-navigation selected-label="{{myLabel}}" id="my_navigation"></my-navigation>
<my-scaffold toolbartitle="{{myLabel}}" id="my_scaffold"></my-scaffold>
</template>
<script>
...
window.addEventListener("WebComponentsReady", function (e) {
document.querySelector("#tpl").myLabel = "Home";
...
});
...
</script>
</body>
There is probably a better way to do that, but you can try this:
<body>
<template id="app" is="dom-bind">
<my-navigation selectedLabel="Home" id="my_navigation"></my-navigation>
<my-scaffold toolbartitle="{{ selectedLabel }}" id="my_scaffold"></my-scaffold>
</template>
<script>
var app = document.querySelector('#app');
app.addEventListener('template-bound', function () {
console.log('Our app is ready to rock!');
});
window.addEventListener('WebComponentsReady', function () {
document.querySelector('body').removeAttribute('unresolved');
var my-navigation = document.querySelector('my-navigation');
// This will add the variable to the 'app' context (template)
app.selectedLabel = my-navigation.selectedLabel;
});
</script>
</body>

Recommendations for managing multiple instances of the same polymer element in a page?

I have a general question. One of the major benefits of building a new polymer element is that it can be used like a native HTML element in a page. So, depending on the element that you build, it's logical that you would be able to add multiple instances of that element in a page.
Say I build a simple task list polymer element that has multiple views. A simple view that just lists the task names in a list and a detailed view that list the tasks and many other properties of the task in a list.
Then I add the element to my page multiple times. Maybe I want one instance of the element to list tasks related to Home and another to list tasks related to Work. But I want to send a link to someone with the Home task list opened in the simple view and the Work task list opened in detailed view. Or maybe I want the Home task list opened in edit mode and the Work task list opened in view mode.
How would you build the element so that you can change attributes/settings to more then one of these elements on a page?
The beauty of polymer is that you can change your component view by just adding / changing attributes to it.
Create custom tags and provide specific attributes depending on your requirement (HOME / WORK profile), and change your view accordingly.
Example:
Step 1: Create task container
<polymer-element name="task-list" noscript>
<template>
<h3>Tasklist</h3>
<core-menu id="tasks">
<content></content>
</core-menu>
</template>
</polymer-element>
Step2: Create task component
<polymer-element name="add-task" attributes="label detail">
<template>
<div id="task">
<input type="checkbox" id="tick" on-click="{{lineThrough}}" /> {{label}}
<div style="color:#999;margin: 5px 25px;">
{{detail}}
</div>
</div>
</template>
<script>
Polymer('add-task', {
lineThrough: function() {
this.$.task.style.textDecoration = this.$.tick.checked ? 'line-through': 'initial';
}
});
</script>
</polymer-element>
And now using above components, you can create your basic task list:
<task-list>
<add-task label="Learn Polymer" detail="http://www.polymer-project.org/"></add-task>
<add-task label="Build something great" detail="create polymer element"></add-task>
</task-list>
Screenshot
Now, To have control over changing task view (list / detailed / editable). Just add 2 attributes to task-list component. To control child view add-task from parent task-list element, you need to publish properties of your child element.
Your child component should be:
<polymer-element name="add-task" attributes="label detail">
<template>
<div id="task">
<template if="{{isEditable}}">
<input value="{{label}}" />
</template>
<template if="{{!isEditable}}">
<input type="checkbox" id="tick" on-click="{{lineThrough}}" /> {{label}}
</template>
<template if="{{isDetailed}}">
<div style="color:#999;margin: 5px 25px;">
{{detail}}
</div>
</template>
</div>
</template>
<script>
Polymer('add-task', {
publish: {
isDetailed: false,
isEditable: false
},
lineThrough: function() {
this.$.task.style.textDecoration = this.$.tick.checked ? 'line-through': 'initial';
}
});
</script>
</polymer-element>
Parent component with required attributes
<polymer-element name="task-list" attributes="editable detailed">
<template>
<h3>Tasklist</h3>
<core-menu flex id="tasks">
<content></content>
</core-menu>
</template>
<script>
Polymer('task-list', {
editable: false,
detailed: false,
domReady: function() {
var items = this.$.tasks.items;
for(var i = 0; i < items.length; i++) {
items[i].isDetailed = this.detailed;
items[i].isEditable = this.editable;
}
}
});
</script>
</polymer-element>
That's it, now you can control your task view by specifying required attributes to your parent component.
<task-list detailed editable>
<add-task label="Learn Polymer" detail="http://www.polymer-project.org/"></add-task>
<add-task label="Build something great" detail="create polymer element"></add-task>
</task-list>
Screenshots
With detailed and editable attributes
Without detailed and editable attributes