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# [Android Components](../../../README.md) > Browser > Errorpages
Responsive browser error pages for Android apps.
## Usage
### Setting up the dependency
Use Gradle to download the library from [maven.mozilla.org](https://maven.mozilla.org/) ([Setup repository](../../../README.md#maven-repository)):
```Groovy
implementation "org.mozilla.components:browser-errorpages:{latest-version}"
```
### Quick Start
If you have an `ErrorType` already at hand, and you want to generate an error page for it with the default template:
```kotlin
val errorType: ErrorType = ErrorType.Unknown
ErrorPages.createErrorPage(context, errorType)
// OR
ErrorPages.createErrorPage(context, errorType, R.raw.custom_html, R.raw.custom_css)
```
If you want to use your own custom HTML template, make sure that you have the following attributes within percentage values (`%`) added to your document so that they can be populated by the engine:
- `pageTitle` - Title of the page.
- `css` - The location of where to place the CSS contents in the document.
- `messageShort` - A one line description of the error message
Gecko and System engines map their respective error codes to the `ErrorType` values.
- `messageLong` - A more detailed message about the error that was seen.
- `button` - Button text that can be clicked on. This is commonly used to reload the page.
For example, here is an HTML error page that will have only a title, short message and some CSS:
```html
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width; user-scalable=false;" />
<title>%pageTitle%</title>
<style>%css%</style>
</head>
<body>
<div>
<h1 class="errorTitleText">%messageShort%</h1>
</div>
</body>
</html>
```
Error Pages are also mostly used along with the `RequestInterceptor`, which can be added to an Engine's Settings:
```kotlin
val settings = DefaultSettings(
requestInterceptor = RequestInterceptor {
override fun onErrorRequest(
session: EngineSession,
errorType: ErrorType,
uri: String?
): RequestInterceptor.ErrorResponse? =
RequestInterceptor.ErrorResponse(ErrorPages.createErrorPage(context, errorType))
}
)
GeckoEngine(settings)
```
See the `ErrorType` enum for the full list of supported error types.
### Engine Support
If you want to add support for another engine, you need to support the `RequestInterceptor` and have it invoked with an `ErrorType` based on the `EngineSession`'s' error code for that request:
```kotlin
class CustomEngineSession(val interceptor: RequestInterceptor) : EngineSession {
override onError(errorCode: Int, uri: String) {
val errorType = when (errorCode) {
1..5 -> ErrorType.ERROR_SECURITY_SSL
else -> ErrorType.ERROR_OFFLINE
}
interceptor.onErrorRequest(session, errorType, uri)
}
}
```
## License
This Source Code Form is subject to the terms of the Mozilla Public
License, v. 2.0. If a copy of the MPL was not distributed with this