Android: AsyncTask
Android: Loader
Android: 01, manifest launchMode. 02, intent lauchmode falg. 03, other lauchmode attrs.
Android: 01, basic usge of Fragment. 02, DialogFragment. 03, ListFramgent. 04, PreferenceFragment. 05, self define ListPreference.
Android: 01, View callback methods. 02, self-define view.