Extension Support and UI Optimisation

Key Files and Changes

• Browser Startup:

  • src/chrome/browser/chrome_browser_main.cc
    Modifications are made to initialize the extension systems as part of Chromium's startup process.
  • Post-Browser Startup Initialization:
    • void ChromeBrowserMainParts::PostBrowserStart()
      Extensions-related services are initialized after the browser startup, including API hooks for extensions to interact with the Android environment. Here, a test extension is loaded from disk as part of the startup process.

• Main Classes in Chromium Codebase:

  • Extension: Represents a single Chrome extension and handles metadata such as permissions, version, etc.
  • ExtensionService: Manages the lifecycle of extensions, including loading, updating, and unloading extensions.
  • ExtensionsRegistry: A centralized registry that tracks all installed extensions, providing APIs to query extension data.

• JNI Wrapper and Java Part:

  • Native C++ part: src/chrome/browser/extensions/extensions_android.cc
  • Java part: src/chrome/android/java/src/org/chromium/chrome/browser/extensions/Extensions.java
    This file provides the Java interface to interact with Chrome extensions on Android. It facilitates communication between the native extension system and the Java components on Android.
  • Extensions Confirmation Dialog:
    • src/chrome/android/java/src/org/chromium/chrome/browser/extensions/ExtensionsConfirmationDialog.java
      This Java class handles UI dialogs for extension installation confirmation, using the Java interface to connect to native C++.

• Extension Installation:

  • src/chrome/browser/download/chrome_download_manager_delegate.cc
    This file was updated to check if a downloaded file is a .crx (Chrome extension) file, and if so, to handle its installation directly within Android Chromium.

• Wootz API:

  • Definitions: src/chrome/common/extensions/api/wootz.json
  • Implementation: src/chrome/browser/extensions/api/wootz/wootz_api.h
    For now, the chrome.wootz.info() function is implemented, which provides detailed information about the device.

Extending chrome.wootz API:

The chrome.wootz API was extended to provide access to specific browser internals. A corresponding wootz.json file defines the API, while the C++ implementation handles API requests from JavaScript. This allows extensions to interact with Android Chromium’s environment seamlessly.