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Is this book for me? The book starts from the very basics installing ember-cli, writing your first template, etc.
If you are just starting out or about to or want to understand fundamental concepts in Ember, the book is definitely for you. Do you offer discounts to students?
Please write me an email and tell me about your school. I'll then send you a discount code for the book. Everything is changing so fast; won't the content be outdated by next week?
As Ember. In practical terms, this means I'll release a book update after each new stable Ember release, once about every six weeks.
I heard Ember is so hard. Will this book help me understand it? I think there are a handful of key concepts in Ember. Once you understand these, Ember is not that hard. The intention of the book is to introduce concepts by way of building an actual application, so you see them applied in practice right away. That also helps the learning process.
I also encourage you to work through the book as you read it, since that makes things sink in even deeper.
You have access to the code repository if you have downloadd the middle- or high-tier package. What if I don't like the book? Read the corresponding RFC here. These controllers are singletons and consequently any state defined on them persists even when the controller is no longer active.
This is something that is very easy to overlook and I stumbled into this, too. In my case, I had a music catalogue app with bands and songs. The songCreationStarted flag on the songs controller indicated that the user has begun creating a song for a particular band. The problem was that if the user then switched to another band, the value of songCreationStarted persisted, and it seemed like the half-finished song was for the other band, which was confusing.
One of the advantages of routeable components is that they have a more consistent lifecycle and always get torn down when transitioning away from their routes.
When they arrive, the above problem will vanish. However, if one forgets to call the parent implementation that I copied above in Ember. Route, one can be in for a long head-scratching session, as the controller will not have its model property set. So always call this. However, there is a greater lesson to be learned here, which is to be mindful of implementations in ancestors.
The init function, defined in Ember. Object, the mother of all objects in Ember, is another example you have to watch out for. The route API has a particularly handy method, modelFor, that can be used in child routes to fetch the model from one of the parent routes, as that model has surely been resolved by that point. For example, the following code is a valid way to fetch the band object in the bands.
If the routes from the above example were slightly altered: Router. With the introduction of block parameters in Ember 1. That trips up a lot of people since they expect the action to be fired the same way that actions from route-driven templates are, on the controller and then bubbling up on the active routes.
What makes this worse is that no error message is logged; the parent component just swallows the error. The general rule is that actions are fired on the current context. In the case of non-component templates, that context is the current controller, while in the case of component templates, it is the parent component if there is one , or again the current controller if the component is not nested. So in the above case, the band-list component would have to re-fire the action received from band-list-item in order to bubble it up to the controller or route.