Develop Reference

How can I delete a block that contains faulty JavaScript breaking the C5 interface?

I was working on an HTML block in Concrete5 located in the footer. I made a javascript call - can't quite remember it, but I think it was referencing either jQuery or the Google Maps API. Anyway, now the block won't display and oddly enough, I am completely unable to modify/add/remove blocks now. I'm pretty sure it is because of the javascript call it is making, but I can't modify or delete the block to fix the issue.
What am I supposed to now? I tried disabling javascript in my browser but of course that won't let me modify the blocks either.

I don't know 5.8+ that well yet, but this may be unfixable from within the UI.
If the error is in a global area, your best bet might be opening the template, changing the area name where the global area is used and displayed, and recreating it from scratch.
You'd be looking for something like this:
$a = new GlobalArea("Footer Nav");
and change the global area's name, thus creating a new one.
If that's not an option, you may have to resort to deleting (or altering) the faulty block through the API.
In my experience, the easiest way to get a blank page that has C5 bootstrapped is creating a custom Dashboard page:
It's a common task for a Concrete5 developer to create their own Dashboard pages. Dashboard pages are just single pages located inside the "single_pages/dashboard" directory. Once they're added within that location, they automatically show up in the Dashboard.
Now, as to how to edit or delete the block inside the area, I don't have a complete recipe, but this example page showing advanced area operations should get you started.
The API documentation for GlobalAreas is here, for Block here (notice the delete() / deleteBlock() methods.)

FYI although the solution marked as best works, it leaves data in the database that will stay there forever and forces you to change your area's name which might be ok once but not if it happens again and again.
Since that was an HTML block, the best way was to go to your database's interface, probably phpMyAdmin, go into the table "btContentLocal" and do a search for the faulty code you had entered in the HTML block then fix or delete it.
Like that you're back to normal, you don't leave stuff behind, and you can keep your area as it is

MWC: how to rerender on URL change

Heyo everyone,
story time - skip if you don't care
I'm just starting out with Meteor + Polymer using Synthesis by #aruntk and I'm very happy about the results and greatful for the time he's invested in this project. There's one issue I'm having though.
I've previously only changed a iron-pages object to change the content of my view. Putting that in a FlowRouter like FlowRouter.route("/", action: {ironpages.select("home");}); works just fine. However, my site is getting more complex and I want to rerender a whole section now. I'm being told to do it reactively which is (to my poor understanding) the preferred way of building Apps here.
tl;dr - skip to here if you don't care about stories
So what I did is just putting mwcLayout.render("test-layout",{"main":"yas-manual-page"}); in my Router action. However, I have to reload to make the changes visible which is not what I want.
the router action is being called when changing the URL
the mwcLayout.render() call works if I reload the page once in the initial building of the site
calling mwcLayout.render() again at a later point does not do anything
I've read up on the topic and people say it's a problem with single-page apps and not building it reactively and whatnot, but I have no idea how this is not reactive. It's reacting to the URL change.
Please, if you have a minute, share some insight with me, I'm really stuck. :slight_smile:
Have a wonderful day y'all!
disclaimer: it's a repost form the Meteor forums which suggests coming here instead.

This behavior is added as a feature of mwc layout to prevent multiple re rendering during each route change. Workarounds here are to create another mwc layout or to set third argument forceRender. From the mwc:layout docs
forceRender
In mwc:layout we dont re render the layout unless the new layout is not equal to the current layout or forceRender argument is set. This is to prevent unwanted rerendering while changing routes(even if you change a param/queryparam the route gets rerun so does the render function written inside FlowRouter action). forceRender comes in handy when you have to change the rendering while keeping the current layout.
...
<mwc-layout id="demo-landing">
<div region="header"></div>
<div region="main"></div>
</mwc-layout>
...
imports/startup/client/router.js
...
action:function(params,queryParams){
mwcLayout.render("demo-landing",{"main":"test-layout1","header":"test-header"});
}
...
Now if you try
mwcLayout.render("demo-landing",{"main":"test-layout2","header":"test-header"});
from console it wont work since layout is not changed and forceRender is not set.
This works->
mwcLayout.render("demo-landing",{"main":"test-layout","header":"test-header"},true);

Callback in Dart when the page is fully loaded

You may know that I totally fell in love with Dart and Polymer and once again, I have a question addressing those two technologies.
My application is a fairly compex polymer app written in Dart. There are some sort of "pages" whereas a page is shown once the user performed an action. The pages contain various types of content and the number of items can reach from zero to a few hundreds.
To enhance the user experience I've build a loader which you can register elements at and once all registered elements loaded, the page is shown. This works and feels pretty amazing but it's way to complicated to make sure to react on all the different states which can occur and overall I am not that happy with the loader thingy.
Thus I wanted to ask if there is anything in Dart or Polymer which helps me to show a loading indicator as long as not everything is fully loaded and once it is done, it hides the loader?

Use an HTML/CSS-only loading indicator and style it so that it becomes hidden when the unresolved attribute is removed from the body. See https://www.polymer-project.org/0.5/articles/styling-elements.html#preventing-fouc

Make DerbyJS only re-render certain DOM nodes

The way DerbyJS (http://derbyjs.com) seems to work at the moment is that it replaces everything in the body tag of the document whenever you click a link.
Is there anyway to say use the template, but replace the content inside #main-content with that instead of the whole body?
Navigation on the left is fixed and doesn't need the benefits of realtime interaction.
Why this is an issue is needing to run some Javascript on the page load to set the size of some containers based on the size of a users browser window, and once I click a link, this setup gets wiped and recreated, and of course, the Javascript doesn't run again, because the document itself hasn't refreshed, just the body.
This would also allow me to write nicer jQuery bindings for the most part, $('element').click(, rather than $('html').on('click','element', ...
Any thoughts, or is this a step too far for this framework at this point in time?
P.S. As I'm only just getting started with Derby, and realtime frameworks in general, maybe what I'm trying to do isn't best practice anyway? I chose Derby because I like the UX part of initial render on the server, then the rest in the client, but sharing routers, which reduces the duplication of code. Open to any better ways of achieving this.

There is no way to rerender part of body on page reload. Just whole body.
You can use app.enter hook to run js code after every page render.
No need to use jQuery bindings, use Derby bindings

I fully agree with Vladimir's answer, just trying to add something to it.
It should be possible to re-render part of the UI through transitional routes (http://derbyjs.com/#routes). In your case it seems like app.enter is the way to go though.

All events in Backbone app fire twice. Occurs randomly

First, some background. I'm fairly certain this is not because of zombie views. I use requireJS and I have only one instance of main views at any given time.
Also, this behavior is random, I haven't been able to reproduce it even once, but several of my users have pointed it out and shown me a video where every click on the app seems to trigger the handler twice. The clicks happen very very fast. It can't be mechanical failure of the mouse because the problem has been reported on multiple machines. The reports are from people with fast Internet connections, for what it's worth.
Is it possible that two instances of the app are running at the same time? Are there any steps I can take to isolate a problem of this kind in backbone?
Apologies for the wall of text, please let me know if I can put up any extra information or relevant pieces of source.
Edit : I've managed to recreate this in Opera. After stepping through part of the code that fires twice (I was inspecting code that opens a modal), I was able to look at the view that triggers the event. Both views have the same CID, so this cannot be attributed to Zombie views right?

In my experience, this is almost always related to zombie views, or other DOM leaks. My best friend in this case if the Web Inspector Profiles -> Take Heap Snapshot and look for detached DOM tree (type "detached" in the search field).
It can occur in tricky cases, even if you think you're only instanciating views once.
Beyond that, you'll have to show us some code ;)

The problem here was that I was running a third party library that reports JS errors. Due to a n error on their part, event bindings on page were affected and this caused the confusion inside the application.
Moral of the story - Whenever you hit an error you feel is impossible, remove your third party dependencies one by one and confirm the problem is your fault to begin with.