# Error handling

The Wowza Flowplayer iOS SDK provides a long list of callbacks for monitoring the player's state. Error callbacks are part of this list, but, in many cases, they may require special handling.

## Localized error messages

There are errors that may not interrupt the content playback (eg. ad-related errors), but there are cases where the playback will be interrupted. In these cases, if you use the built-in controls, a meaningful message will be presented to the user together with a reload button. You can change these messages or provide translations to languages other than English by overriding the following string keys in your target's `Localizable.strings`:


```swift
// An error related to the playback has occurred.
"flowplayer-error-playback" = "Failed to play media.";

// The access token could not be validated and therefore the playback cannot start.
"flowplayer-error-access-token" = "Failed to validate access token.";

// Failed to load a Flowplayer config.
"flowplayer-error-config" = "Failed to load media.";

// Failed to load the built-in controls. This probably happened due to poor or no Internet connection.
"flowplayer-error-controls" = "Failed to load built-in controls.";

// This message will actually not be shown to the user since the playback will not be interrupted. The message will be included in the error callback though.
"flowplayer-error-ad" = "Failed to load ad.";

// This actually should not happen but it works as a fallback in case some other (really) unexpected error has occurred.
"flowplayer-error-unknown" = "An unknown error has occurred.";
```

If you wish to force a locale programmatically and override the default system language, then the simplest solution is to update the `UserDefaults`. The following example will force the local to French (Canada).


```swift
// Note that you need to use an underscore (_) and not a dash (-).
UserDefaults.standard.set(["fr_CA"], forKey: "AppleLanguages")
UserDefaults.standard.synchronize()
```

Alternatively, you can write the following extension:


```swift
extension Bundle {
    private static var bundle: Bundle!

    public static func setLanguage(lang: String) {
        UserDefaults.standard.set(lang, forKey: "app_lang")
        let path = Bundle.main.path(forResource: lang, ofType: "lproj")
        bundle = Bundle(path: path!)
    }
}
```

Then use it like this:


```swift
// Note that you need to use a dash (-) and not an underscore (_).
Bundle.setLanguage(lang: "fr-CA")
```

Regardless of which of the two alternatives you choose to use, you still need to override Wowza Flowplayer's string keys in your target's `Localizable.strings` as was mentioned at the top of this section.

## Reload player

Finally, if the playback has been interrupted, you may want to reload the player without having to call `prepare()` again. This can be achieved by calling:


```swift
flowplayerViewController.reload()
```