Java tutorial
/* * Tweetings - Twitter client for Android * * Copyright (C) 2012-2013 RBD Solutions Limited <apps@tweetings.net> * Copyright (C) 2012 Mariotaku Lee <mariotaku.lee@gmail.com> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package com.dwdesign.tweetings.fragment; import java.util.Timer; import java.util.TimerTask; import com.dwdesign.tweetings.adapter.CursorStatusesAdapter; import com.dwdesign.tweetings.app.TweetingsApplication; import com.dwdesign.tweetings.provider.TweetStore.Statuses; import com.dwdesign.tweetings.util.ServiceInterface; import android.app.Activity; import android.content.BroadcastReceiver; import android.content.ContentResolver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.content.SharedPreferences; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.os.Handler; import android.support.v4.content.Loader; import android.util.Log; import android.view.MotionEvent; import android.view.View; import android.view.View.OnTouchListener; import android.view.ViewGroup; import android.widget.AbsListView; import android.widget.AbsListView.OnScrollListener; import android.widget.ListView; public class HomeTimelineFragment extends CursorStatusesListFragment implements OnTouchListener { private SharedPreferences mPreferences; private ListView mListView; private ServiceInterface mService; private boolean isVisibleToUser = false; private boolean mShouldRestorePosition = false; private long mMinIdToRefresh; private Timer syncTimer; private Activity mActivity; private boolean isReadTrackingSuspended = false; private final BroadcastReceiver mStatusReceiver = new BroadcastReceiver() { @Override public void onReceive(final Context context, final Intent intent) { final String action = intent.getAction(); final Bundle extras = intent.getExtras(); if (BROADCAST_HOME_TIMELINE_REFRESHED.equals(action)) { onRefreshComplete(); if (extras != null) { mMinIdToRefresh = extras.getBoolean(INTENT_KEY_SUCCEED) ? extras.getLong(INTENT_KEY_MIN_ID, -1) : -1; } else { mMinIdToRefresh = -1; } if (mPreferences.getBoolean(PREFERENCE_KEY_SYNC_ENABLED, false)) { HomeTimelineFragment.this.scrollToSavedPosition(); } } else if (BROADCAST_HOME_TIMELINE_DATABASE_UPDATED.equals(action)) { if (isAdded() && !isDetached()) { getLoaderManager().restartLoader(0, null, HomeTimelineFragment.this); } } else if (BROADCAST_REFRESHSTATE_CHANGED.equals(action)) { if (mService.isHomeTimelineRefreshing()) { setRefreshing(false); } } } }; // Begin Sync Code private BroadcastReceiver receiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { final String action = intent.getAction(); if (TweetingsApplication.BROADCAST_SYNC_ACTION.equals(action)) { String syncType = intent.getExtras().getString(TweetingsApplication.PARAM_SYNC_TYPE); String syncId = intent.getExtras().getString(TweetingsApplication.PARAM_SYNC_ID); if (syncType.equals("timeline")) { HomeTimelineFragment.this.syncPositionReceived = syncId; HomeTimelineFragment.this.scrollToSavedPosition(); } } else if (BROADCAST_VOLUME_UP.equals(action)) { if (isVisible()) { int currentPosition = mListView.getFirstVisiblePosition(); if (currentPosition == 0) return; mListView.setSelection(currentPosition - 1); mListView.clearFocus(); } } else if (BROADCAST_VOLUME_DOWN.equals(action)) { if (isVisible()) { int currentPosition = mListView.getFirstVisiblePosition(); if (currentPosition == mListView.getCount() - 1) return; mListView.setSelection(currentPosition + 1); mListView.clearFocus(); } } } }; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mActivity = getActivity(); } @Override public void onDestroy() { super.onDestroy(); if (syncTimer != null) { syncTimer.cancel(); } } @Override public void onResume() { super.onResume(); IntentFilter filter = new IntentFilter(); filter.addAction(TweetingsApplication.BROADCAST_SYNC_ACTION); filter.addAction(BROADCAST_VOLUME_UP); filter.addAction(BROADCAST_VOLUME_DOWN); registerReceiver(receiver, filter); if (mPreferences.getBoolean(PREFERENCE_KEY_SYNC_ENABLED, false)) { getSync(); } } @Override public void setMenuVisibility(final boolean visible) { super.setMenuVisibility(visible); isVisibleToUser = visible; } @Override public void onPause() { super.onPause(); if (mPreferences.getBoolean(PREFERENCE_KEY_SYNC_ENABLED, false)) { saveSync(); } unregisterReceiver(receiver); } public void scheduleSync() { if (syncTimer != null) { syncTimer.cancel(); syncTimer = null; } syncTimer = new Timer(); syncTimer.schedule(new TimerTask() { @Override public void run() { HomeTimelineFragment.this.saveSync(); } }, 4000); } protected void saveSync() { final CursorStatusesAdapter adapter = getListAdapter(); int currentPosition = getListView().getFirstVisiblePosition(); long accountid = com.dwdesign.tweetings.util.Utils.getDefaultAccountId(getActivity()); String username = com.dwdesign.tweetings.util.Utils.getAccountUsername(getActivity(), accountid); long statusId = adapter.findItemIdByPosition(currentPosition); TweetingsApplication app = (TweetingsApplication) getApplication(); app.saveSync("timeline", "" + statusId, accountid, username); if (syncTimer != null) { syncTimer.cancel(); } } protected void getSync() { String syncTimeline = "timeline"; final long accountid = com.dwdesign.tweetings.util.Utils.getDefaultAccountId(getActivity()); final String username = com.dwdesign.tweetings.util.Utils.getAccountUsername(getActivity(), accountid); getApplication().getSync(syncTimeline, accountid, username); //scrollToSavedPosition(); } protected void scrollToSavedPosition() { final CursorStatusesAdapter adapter = getListAdapter(); try { if (this.syncPositionReceived != null && !this.syncPositionReceived.equals("(null)")) { if ((this.syncPositionReceived != null && this.syncPosition == null) || (this.syncPositionReceived != null && this.syncPosition != null && !this.syncPositionReceived.equals(this.syncPosition))) { int index = adapter.findItemPositionByStatusId(Long.parseLong(this.syncPositionReceived)); this.scrollStatusId = this.syncPositionReceived; this.syncPosition = this.syncPositionReceived; if (index >= 0 && index < adapter.getCount()) { mListView.setSelection(index); } else if (index == -1) { int guessedPosition = adapter .findNearestItemPositionByStatusId(Long.parseLong(this.syncPositionReceived)); if (guessedPosition > 0) { getListView().setSelection(guessedPosition); } } } } } catch (NumberFormatException ex) { } } // End Sync code @Override public Uri getContentUri() { return Statuses.CONTENT_URI; } @Override public int getStatuses(final long[] account_ids, final long[] max_ids, final long[] since_ids) { //if (max_ids == null) return mService.refreshAll(); isReadTrackingSuspended = true; return mService.getHomeTimelineWithSinceId(account_ids, max_ids, since_ids); } @Override public void onActivityCreated(final Bundle savedInstanceState) { mPreferences = getSharedPreferences(SHARED_PREFERENCES_NAME, Context.MODE_PRIVATE); mShouldRestorePosition = true; mService = getServiceInterface(); super.onActivityCreated(savedInstanceState); mListView = getListView(); //mListView.setDescendantFocusability(ViewGroup.FOCUS_AFTER_DESCENDANTS); mListView.setOnTouchListener(this); } @Override public void onLoadFinished(final Loader<Cursor> loader, final Cursor data) { isReadTrackingSuspended = true; final Handler handler = new Handler(); handler.postDelayed(new Runnable() { @Override public void run() { isReadTrackingSuspended = false; } }, 500); final CursorStatusesAdapter adapter = getListAdapter(); long last_viewed_id = -1; { final int position = mListView.getFirstVisiblePosition(); if (position > 0) { last_viewed_id = adapter.findItemIdByPosition(position); } } super.onLoadFinished(loader, data); final boolean remember_position = mPreferences.getBoolean(PREFERENCE_KEY_REMEMBER_POSITION, true); if (gapStatusId > 0) { if (mPreferences.getBoolean(PREFERENCE_KEY_GAP_POSITION, true)) { scrollToStatusId(gapStatusId); } gapStatusId = -1; return; } if (mShouldRestorePosition && remember_position) { final long status_id = mPreferences.getLong(PREFERENCE_KEY_SAVED_HOME_TIMELINE_ID, -1); final int position = adapter.findItemPositionByStatusId(status_id); if (position > -1 && position < mListView.getCount()) { mListView.setSelection(position); } mShouldRestorePosition = false; return; } if (mMinIdToRefresh > 0 && remember_position) { final int position = adapter .findItemPositionByStatusId(last_viewed_id > 0 ? last_viewed_id : mMinIdToRefresh); if (position >= 0 && position < mListView.getCount()) { mListView.setSelection(position); } mMinIdToRefresh = -1; return; } final int position = adapter .findItemPositionByStatusId(last_viewed_id > 0 ? last_viewed_id : mMinIdToRefresh); if (position > 0) { mListView.setSelection(position); } } @Override public void onScrollStateChanged(final AbsListView view, final int scrollState) { super.onScrollStateChanged(view, scrollState); switch (scrollState) { case SCROLL_STATE_IDLE: HomeTimelineFragment.this.scheduleSync(); final int first_visible_position = view.getFirstVisiblePosition(); final long status_id = getListAdapter().findItemIdByPosition(first_visible_position); mPreferences.edit().putLong(PREFERENCE_KEY_SAVED_HOME_TIMELINE_ID, status_id).commit(); break; case SCROLL_STATE_TOUCH_SCROLL: if (syncTimer != null) { syncTimer.cancel(); } break; } } @Override public void onStart() { super.onStart(); final IntentFilter filter = new IntentFilter(BROADCAST_HOME_TIMELINE_REFRESHED); filter.addAction(BROADCAST_ACCOUNT_LIST_DATABASE_UPDATED); filter.addAction(BROADCAST_HOME_TIMELINE_DATABASE_UPDATED); filter.addAction(BROADCAST_REFRESHSTATE_CHANGED); registerReceiver(mStatusReceiver, filter); if (mService.isHomeTimelineRefreshing()) { setRefreshing(false); } else { onRefreshComplete(); } } @Override public void onStop() { unregisterReceiver(mStatusReceiver); super.onStop(); } @Override public boolean onTouch(final View view, final MotionEvent ev) { switch (ev.getAction()) { case MotionEvent.ACTION_DOWN: { mService.clearNotification(NOTIFICATION_ID_HOME_TIMELINE); break; } } return false; } @Override public void onScroll(final AbsListView view, final int firstVisibleItem, final int visibleItemCount, final int totalItemCount) { super.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount); if (firstVisibleItem == 0 && !isReadTrackingSuspended) { Intent intent = new Intent(BROADCAST_TABS_READ_TWEETS); intent.putExtra(INTENT_KEY_UPDATE_TAB, TAB_HOME); mActivity.sendBroadcast(intent); } else if (firstVisibleItem > 0 && isReadTrackingSuspended) { final Handler handler = new Handler(); handler.postDelayed(new Runnable() { @Override public void run() { isReadTrackingSuspended = false; } }, 500); } } }