Aurelia - dynamically create custom element in a view-model - aurelia

I have an Aurelia app where a user can click on a button and create a new tab. The tab and its content (a custom element) do not exist on the page before the user clicks the button. I am generating the HTML for the content at runtime (via Javascript) in my view model.
I keep seeing mention of using the template engine's compose or enhance functions, but neither are working for me. I don't know how I would use the <compose> element (in my HTML) since I am creating the element based on the user clicking a button.
My thought was that the button has a click.delegate to a function that does ultimately does something like
const customElement = document.createElement('custom-element');
parentElement.appendChild(customElement);
const view = this.templatingEngine.enhance({
element : customElement,
container : this.container, // injected
resources : this.viewResources, // injected
bindingContext: {
attrOne: this.foo,
attrTwo: this.bar,
}
});
view.attached();
But all this does is create an HTML element <custom-element></custom-element> without actually binding any attributes to it.
How can I create a custom element analogous to <custom-element attr-one.bind="foo" attr-two.bind="bar"></custom-element> but via Javascript?

As you pointed out in your own answer, it's the missing resources that caused the issue. One solution is to register it globally. That is not always the desired behavior though, as sometimes you want to lazily load the resources and enhance some lazy piece of HTML. Enhance API accepts an option for the resources that you want to compile the view with. So you can do this:
.enhance({
resources: new ViewResources(myGlobalResources) // alter the view resources here
})
for the view resources, if you want to get it from a particular custom element, you can hook into the created lifecycle and get it, or you can inject the container and retrieve it via container.get(ViewResources)

I found the problem =\ I had to make my custom element a global resource.

Related

Does OutletService support dynamically adding component in button handler

i used this.outletService.add('BottomHeaderSlot', factory, OutletPosition.BEFORE); during the search button click handler to add a custom component in the BottomHeaderSlot. I intended to add searchOverlay under the header to add customized search behavior.
But my custom component is not shown under the header after calling outletService.add. I refered to this https://sap.github.io/cloud-commerce-spartacus-storefront-docs/outlets/ . Does outletService support dynamic adding component during runtime?
Following is my button handler
open(): void {
const factory = this.componentFactoryResolver.resolveComponentFactory<SearchOverlayComponent>(SearchOverlayComponent);
this.outletService.add('BottomHeaderSlot', <any>factory, OutletPosition.BEFORE);
this.cd.markForCheck();
That's a good question. At the moment it is a not a feature supported from our outlets.
A solution you could do is inject the component in a more static manner (either CMS or outlet when the app initializes like seen here https://github.com/SAP/cloud-commerce-spartacus-storefront/blob/develop/projects/storefrontlib/src/cms-components/asm/services/asm-enabler.service.ts)?
Your component could then be wrapped with an <ng-container *ngIf="open$ | async></ng-container> where open$ is an observable for the state of the search box. That way the component only appears in the dom when the searchbox is open.
The idea of dynamically adding a components through outlets is a good one we will keep in mind. I will open an issue on Github as an improvement.

Initialize dynamic Component in Code using Vue.js

I am currently developing a web application that is used to display elements for events on a map provided by HERE Maps. I am using Vue.
I have some components, but the relevant component is the component HereMaps.vue which initializes the map using the HERE Maps Api.
The HERE Maps Api provides the possibility to place so called InfoBubbles on the map showing additional information. These InfoBubbles can be provided some HTML-code in order to customize their appearance.
Please refer to the documentation for additional information
Following the documentation the code looks something like this:
let bubble = new H.ui.InfoBubble(marker.getPosition(), {
content: "<div class='someClass'>Some Content</div>"
});
this.ui.addBubble(bubble)
This is happening after mount in the "mounted" method from Vue in the "HereMaps" component.
The Bubbles are added in a "closed" (hidden) form and dynamically "opened" to reveal their content when the corresponding marker icon on the map is clicked. Therefore the HTML-code is present on the DOM after the component is mounted and is not removed at a later stage.
Now instead of supplying custom code within each bubble added to the UI i want to just add a component like this:
let bubble = new H.ui.InfoBubble(marker.getPosition(), {
content: "<myDynamicComponent></myDynamicComponent>"
});
this.ui.addBubble(bubble)
It does not matter to me wether the component is initialized using props or if it is conditionally rendered depending on the state of a global variable. I just want to be able to use the "myDynamicComponent" in order to customize the appearance in a different file. Otherwise the design process gets very messy.
As far as i know this is not possible or at least i was not able to get it work. This is probably due to the fact that the "myDynamicComponent" is not used within the "template" of the "HereMaps" component und thus Vue does not know that it needs to render something here after the directive is added to the DOM in the "mounted" method.
This is what the InfoBubble looks using normal HTML as an argument:
This is what the InfoBubble looks using the component as an argument:
It appears to just be empty. No content of the "myDynamicComponent" is shown.
Does anyone have any idea how i could solve this problem.
Thank You.
Answer is a bit complicated and I bet you wouldn't like it:)
content param can accept String or Node value. So you can make new Vue with rendered your component and pass root element as content param.
BTW, Vue does not work as you think, <myDynamicComponent></myDynamicComponent> bindings, etc exists in HTML only in compile time. After that all custom elements(components) are compiled to render functions. So you can't use your components in that way.
Give us fiddle with your problem, so we can provide working example:)

Aurelia Routing: Append Views into Tabbed Interface

I'm practically brand new to Aurelia, but over the course of a few days I've picked up the starter template and gone through some video training in Pluralsight. I have a unique vision that I can't seem to decide whether compose element, custom element, or router is best to use for this scenario - or if I need to write something completely custom.
I prefer to continue using the router because it gives you the
URLs and history state. Linking deep within the web app may be necessary.
When a view / viewmodel is initialized, I want the view appended to the DOM, NOT replaced. The <router-view> element works by replacing the view.
With each view appended to the DOM, I would like to create a set of tabs representing every view that has been opened so far. Think of any modern text editor, IDE, or even a web browser shows tabs.
Sometimes it would be necessary to detect whether a view is already rendered in the DOM (viewmodel + parameter) and just bring that view to the front -vs- appending the new one.
Do you have any suggestions, examples, etc for someone relatively new to Aurelia, SPAs, and MVVM?
Thank you.
I believe the easiest way is using the compose element. You would need an array containing all screens, and another array to hold the opened screens. Something like this:
screens = [
{ id: 1, name: 'Test 1', view: './test-1.html', viewModel: './test-1' },
{ id: 2, name: 'Test 2', view: './test-2.html', viewModel: './test-2' }
];
_activeScreens = [];
get activeScreens() {
return this.screens.filter((s) => this._activeScreens.indexOf(s.id) !== -1);
}
In the HTML you just have to use <compose></compose> for each iteration of activeScreens.
I made this example https://gist.run/?id=c32f322b1f56e6f0a83679512247af7b to show you the idea. In my case, I've used an html table. In your case, you could use a tab plugin, like Bootstrap or jQuery.
Hope this helps!

Attach/Render RactiveJS component outside of template

I've got an existing SPA that was developed using nested RactiveJS components. Which is great, and offers a ton of flexibility throughout the entire app. Currently I attempting to add in client side routing support using page. My navigation switches out high-level components using simple {{#visible}}{{/visible}} template markup on each component. This is a little troublesome in its current state as it always kicks off a re-render whenever the high-level component becomes visible again.
Is there a way to render a component, for example, called widget, without using the
<widget></widget>
method? I've already "registered" the component with the parent, but obviously when constructing it by means of
new App.components.widget
I am able to control how/when it's rendered/inserted/detached, but lose the recognition in the application's component hierarchy.
There is insert exactly for that. You don't even need to "register" it to the component you plan to put it to. You can use the different find* methods or nodes to easily retrieve a reference of your planned container element.
var instance = new YourDetachedWidget({ ... });
instance.insert('#your-container'); // This could be a node, selector or jQuery object

How can I embed a twitter timeline in a Durandal view?

The code to embed the widget is nice and simple, but it includes javascript in tags.
Durandal appears to strip out such script tags.
How do I use the embed code in a Durandal view?
https://dev.twitter.com/web/embedded-timelines
<a class="twitter-timeline" href="https://twitter.com/XXX" data-widget-id="XXX">Tweets by #XXX</a>
<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+"://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
You would need to write a custom Knockout binding, or create a Durandal widget where the view is your tag, and the viewModel handles the JavaScript in your tag.
Some notes: In your widget's view model, you would avoid d.getElementsByTagName(s) in favor of simply referencing the view reference passed in to either the attached or compositionComplete handler that Durandal provides. In fact, you could pretty much eschew all direct DOM manipulation in favor of Durandal's imported view references and Knockout's/Durandal's templating/composition.
UPDATE
Take a look at this from the documentation you reference: "If you’re already including our ‘widgets.js’ JavaScript in your page to show embedded Tweets or Twitter buttons, you don’t need to include this script again; it updates automatically to support new features."
This could lead you down the path of simply referencing widgets.js in a script tag in your index.html or index.chtml file.
You cannot use script tags in Durandal views, but you can use them in your index page.
SECOND UPDATE
Once widget.js has been referenced in a script tag in the index.html or index.chtml (or perhaps even by using AMD), it becomes a matter of choosing the proper Durandal point at which to load the Twitter widget. This could be either in the attached handler or in the compositionComplete handler, as indicated above.
As the OP pointed out in his comments, a functional place to do this is compositionComplete, in the following manner:
var compositionComplete = function () {
twttr.widgets.load();
}
as documented here.
This assumes that twttr is either on the window or injected into the viewModel.
POSSIBLE MEMORY LEAK
It is equally important to note that unloading of widgets must take place in the Durandal's detached handler. Use Twitter's API to unload, and then be sure to nullify the windows reference.