'Check for Updates button clicked. Manually force an update check.'

def check_for_updates(self):

    common.log('SettingsDialog', 'check_for_updates')
    self._disable_buttons()
    self.qtapp.processEvents()
    def update_available(update_url, installed_version, latest_version):
        Alert(strings._('update_available', True).format(update_url, installed_version, latest_version))
    def update_not_available():
        Alert(strings._('update_not_available', True))
    u = UpdateChecker(self.onion)
    u.update_available.connect(update_available)
    u.update_not_available.connect(update_not_available)
    try:
        u.check(force=True)
    except UpdateCheckerCheckError:
        Alert(strings._('update_error_check_error', True), QtWidgets.QMessageBox.Warning)
    except UpdateCheckerInvalidLatestVersion as e:
        Alert(strings._('update_error_invalid_latest_version', True).format(e.latest_version), QtWidgets.QMessageBox.Warning)
    self._enable_buttons()
    settings = Settings(self.config)
    settings.load()
    autoupdate_timestamp = settings.get('autoupdate_timestamp')
    self._update_autoupdate_timestamp(autoupdate_timestamp)
