VideoUploader.java 文件源码

private static void registerAccessTokenTracker() {
    accessTokenTracker = new AccessTokenTracker() {
        @Override
        protected void onCurrentAccessTokenChanged(
                AccessToken oldAccessToken,
                AccessToken currentAccessToken) {
            if (oldAccessToken == null) {
                // If we never had an access token, then there would be no pending uploads.
                return;
            }

            if (currentAccessToken == null ||
                    !Utility.areObjectsEqual(
                            currentAccessToken.getUserId(),
                            oldAccessToken.getUserId())) {
                // Cancel any pending uploads since the user changed.
                cancelAllRequests();
            }
        }
    };
}