question: @ Override public boolean onPreferenceTreeClick ( PreferenceScreen preferenceScreen , Preference preference ) { log ( "onPreferenceTreeClick: preference=" + preference ) ; if ( preference == mAirplaneModePreference && Boolean . parseBoolean ( SystemProperties . get ( TelephonyProperties . PROPERTY_INECM_MODE ) ) ) { startActivityForResult ( new Intent ( TelephonyIntents . ACTION_SHOW_NOTICE_ECM_BLOCK_OTHERS , null ) , REQUEST_CODE_EXIT_ECM ) ; return true ; } else if ( preference == findPreference ( KEY_MANAGE_MOBILE_PLAN ) ) { onManageMobilePlanClick ( ) ; } return super . onPreferenceTreeClick ( preferenceScreen , preference ) ; }
target:  Invoked on each preference click in this hierarchy, overrides PreferenceActivity's implementation.  Used to make sure we track the preference click events.