Disable Android WebView/WebViewClient Initiated favicon.ico Request

Disable Android WebView/WebViewClient Initiated favicon.ico Request

Android WebViews, by default, automatically attempt to fetch the favicon.ico file for every website loaded. This can result in unnecessary network requests, impacting performance, particularly on slow networks. This article explores methods to disable these automatic favicon.ico requests in your Android WebView applications.

Understanding the Issue

The issue arises because Android’s WebView, by default, fetches favicon.ico using the provided URL and not necessarily the root domain. This often results in redundant requests, especially when websites don’t have a favicon.ico present, leading to performance degradation.

Example

Consider a website hosted at “https://example.com”. The WebView might attempt to fetch “https://example.com/favicon.ico”, even if the website doesn’t have a favicon.ico file. This leads to a wasted network request.

Disabling Favicon Requests

Here are several methods to disable automatic favicon.ico requests:

1. Override the `shouldInterceptRequest` Method

The most effective approach is to override the `shouldInterceptRequest` method in your `WebViewClient` implementation. This method gives you control over every network request made by the WebView.

Code Example

import android.webkit.WebView;
import android.webkit.WebViewClient;

// ...

class MyWebViewClient extends WebViewClient {
  @Override
  public android.webkit.WebResourceResponse shouldInterceptRequest(WebView view, String url) {
    if (url.endsWith("favicon.ico")) {
      return new WebResourceResponse(null, null, null); // Cancel the request
    }
    return super.shouldInterceptRequest(view, url);
  }
}

2. Modify the `settings` Object

Alternatively, you can modify the `settings` object of your WebView to control specific features. The following code disables the automatic favicon loading. However, it doesn’t completely eliminate the requests, as they might still be triggered by other internal mechanisms.

Code Example

import android.webkit.WebView;
import android.webkit.WebSettings;

// ...

webView.getSettings().setLoadsImagesAutomatically(true); // Adjust this as needed
webView.getSettings().setSupportZoom(true);
webView.getSettings().setDisplayZoomControls(false);
webView.getSettings().setBuiltInZoomControls(true);
webView.getSettings().setUseWideViewPort(true);
webView.getSettings().setLoadWithOverviewMode(true);
webView.getSettings().setDomStorageEnabled(true);
webView.getSettings().setDatabaseEnabled(true);
webView.getSettings().setAppCacheEnabled(true);
webView.getSettings().setCacheMode(WebSettings.LOAD_DEFAULT); 
webView.getSettings().setLoadsImagesAutomatically(false); // Disables favicon loading 

3. Use `onReceivedError`

This approach is less precise than the `shouldInterceptRequest` method. It relies on intercepting errors from the favicon requests. This method might not be reliable in all scenarios, as the error handling for favicons might vary.

Code Example

import android.webkit.WebView;
import android.webkit.WebViewClient;

// ...

class MyWebViewClient extends WebViewClient {
  @Override
  public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
    if (failingUrl.endsWith("favicon.ico")) {
      // Handle the error and ignore the favicon request
    } else {
      // Handle the error normally
      super.onReceivedError(view, errorCode, description, failingUrl);
    }
  }
}

4. Modify the `webResourceResponse` for Favicon Requests

Another technique is to explicitly provide an empty `WebResourceResponse` when the WebView attempts to load the favicon.ico. This method effectively cancels the request.

Code Example

import android.webkit.WebView;
import android.webkit.WebViewClient;

// ...

class MyWebViewClient extends WebViewClient {
  @Override
  public WebResourceResponse shouldInterceptRequest(WebView view, String url) {
    if (url.endsWith("favicon.ico")) {
      return new WebResourceResponse(null, null, null);
    }
    return super.shouldInterceptRequest(view, url);
  }
}

Comparison of Methods

Conclusion

Disabling automatic favicon.ico requests in your Android WebView application can significantly improve performance, especially in resource-constrained environments. Choose the most suitable method based on your application’s needs and complexity requirements. The `shouldInterceptRequest` method offers the most robust solution, while the `settings` object provides a quick and simple alternative.