Error Handling

Having errors on a book reader is uncommon, things should always pretty much work assuming the library and/or your app does not have "bugs". Some processing such as unzipping archives, fetching resources or rendering complexe documents such as PDF can lead to errors but are usually well handled.

Granular errors vs Globals

For convenience you can handle errors on a global level and just make your entire reader in error state or decide to handle them in a more granular way. One of the most likely component to fail are the Spine items. Check below sections to see how you can listen to errors within prose.

Errors in Spine Item

SpineItem instances have an error state that you can access when problem occurs. An error can potentially occurs when the resource is fetched for example, or during rendering if you have a complexe document handling. That being said, the most typical issue is usually network request error when fetching resources.

You can take advantage of the error state to display a placeholder page to let the user know something went wrong.

Our default placeholder pages are using spine item various states to display different state. You can look at it for some example.