Java tutorial
/** * Android ownCloud News * * @author David Luhmer * @copyright 2013 David Luhmer david-dev@live.de * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE * License as published by the Free Software Foundation; either * version 3 of the License, or any later version. * * This library 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 AFFERO GENERAL PUBLIC LICENSE for more details. * * You should have received a copy of the GNU Affero General Public * License along with this library. If not, see <http://www.gnu.org/licenses/>. * */ package com.quarterfull.newsAndroid; import android.content.Context; import android.content.SharedPreferences; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.os.AsyncTask; import android.os.Bundle; import android.os.Parcelable; import android.preference.PreferenceManager; import android.support.v4.app.Fragment; import android.support.v4.content.ContextCompat; import android.support.v4.view.GestureDetectorCompat; import android.support.v4.widget.SwipeRefreshLayout; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.DefaultItemAnimator; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.helper.ItemTouchHelper; import android.util.AttributeSet; import android.util.Log; import android.view.GestureDetector; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import android.widget.ProgressBar; import org.apache.commons.lang3.time.StopWatch; import java.util.List; import butterknife.Bind; import butterknife.ButterKnife; import com.quarterfull.newsAndroid.ListView.SubscriptionExpandableListAdapter; import com.quarterfull.newsAndroid.adapter.DividerItemDecoration; import com.quarterfull.newsAndroid.adapter.NewsListRecyclerAdapter; import com.quarterfull.newsAndroid.adapter.ViewHolder; import com.quarterfull.newsAndroid.database.DatabaseConnectionOrm; import com.quarterfull.newsAndroid.database.DatabaseConnectionOrm.SORT_DIRECTION; import com.quarterfull.newsAndroid.database.model.RssItem; import com.quarterfull.newsAndroid.database.model.RssItemDao; import com.quarterfull.newsAndroid.helper.AsyncTaskHelper; /** * A fragment representing a single NewsReader detail screen. This fragment is * either contained in a {@link NewsReaderListActivity} in two-pane mode (on * tablets) or a {@link NewsReaderListActivity} on handsets. */ public class NewsReaderDetailFragment extends Fragment { protected final String TAG = getClass().getCanonicalName(); private Long idFeed; private Drawable markAsReadDrawable; private Drawable starredDrawable; private int accentColor; private Parcelable layoutManagerSavedState; /** * @return the idFeed */ public Long getIdFeed() { return idFeed; } Long idFolder; /** * @return the idFolder */ public Long getIdFolder() { return idFolder; } String titel; /** * @return the titel */ public String getTitel() { return titel; } private int onResumeCount = 0; private static final String LAYOUT_MANAGER_STATE = "LAYOUT_MANAGER_STATE"; private boolean mMarkAsReadWhileScrollingEnabled; @Bind(R.id.pb_loading) ProgressBar pbLoading; @Bind(R.id.tv_no_items_available) View tvNoItemsAvailable; @Bind(R.id.list) RecyclerView recyclerView; @Bind(R.id.swipeRefresh) SwipeRefreshLayout swipeRefresh; /** * Mandatory empty constructor for the fragment manager to instantiate the * fragment (e.g. upon screen orientation changes). */ public NewsReaderDetailFragment() { } public void setData(Long idFeed, Long idFolder, String titel, boolean updateListView) { Log.v(TAG, "Creating new itstance"); this.idFeed = idFeed; this.idFolder = idFolder; this.titel = titel; ((AppCompatActivity) getActivity()).getSupportActionBar().setTitle(titel); if (updateListView) UpdateCurrentRssView(getActivity()); else RefreshCurrentRssView(); } @Override public void onResume() { Log.v(TAG, "onResume called!"); SharedPreferences mPrefs = PreferenceManager.getDefaultSharedPreferences(getActivity()); mMarkAsReadWhileScrollingEnabled = mPrefs .getBoolean(SettingsActivity.CB_MARK_AS_READ_WHILE_SCROLLING_STRING, false); //When the fragment is instantiated by the xml file, onResume will be called twice if (onResumeCount >= 2) { RefreshCurrentRssView(); } onResumeCount++; super.onResume(); } private void handleMarkAsReadScrollEvent() { LinearLayoutManager linearLayoutManager = (LinearLayoutManager) recyclerView.getLayoutManager(); int firstVisibleItem = linearLayoutManager.findFirstVisibleItemPosition(); int lastVisibleItem = linearLayoutManager.findLastVisibleItemPosition(); int visibleItemCount = lastVisibleItem - firstVisibleItem; int totalItemCount = recyclerView.getAdapter().getItemCount(); NewsListRecyclerAdapter adapter = (NewsListRecyclerAdapter) recyclerView.getAdapter(); //Set the item at top to read ViewHolder vh = (ViewHolder) recyclerView.findViewHolderForLayoutPosition(firstVisibleItem); if (vh != null && !vh.shouldStayUnread()) { adapter.ChangeReadStateOfItem(vh, true); } //Check if Listview is scrolled to bottom if (lastVisibleItem == (totalItemCount - 1) && visibleItemCount != 0 && //Check if list is empty recyclerView.getChildAt(visibleItemCount).getBottom() <= recyclerView.getHeight()) { for (int i = firstVisibleItem; i <= lastVisibleItem; i++) { RecyclerView.ViewHolder vhTemp = recyclerView.findViewHolderForLayoutPosition(i); if (vhTemp instanceof ViewHolder) { //Check for ViewHolder instance because of ProgressViewHolder vh = (ViewHolder) vhTemp; if (vh != null && !vh.shouldStayUnread()) { adapter.ChangeReadStateOfItem(vh, true); } } } } } public void UpdateMenuItemsState() { NewsReaderListActivity nla = (NewsReaderListActivity) getActivity(); if (nla.getMenuItemDownloadMoreItems() != null) { if (idFolder != null && idFolder == SubscriptionExpandableListAdapter.SPECIAL_FOLDERS.ALL_UNREAD_ITEMS.getValue()) { nla.getMenuItemDownloadMoreItems().setEnabled(false); } else { nla.getMenuItemDownloadMoreItems().setEnabled(true); } } } public void notifyDataSetChangedOnAdapter() { NewsListRecyclerAdapter nca = (NewsListRecyclerAdapter) recyclerView.getAdapter(); if (nca != null) nca.notifyDataSetChanged(); } /** * Refreshes the current RSS-View */ public void RefreshCurrentRssView() { Log.v(TAG, "RefreshCurrentRssView"); NewsListRecyclerAdapter nra = ((NewsListRecyclerAdapter) recyclerView.getAdapter()); nra.refreshAdapterDataAsync(new NewsListRecyclerAdapter.IOnRefreshFinished() { @Override public void OnRefreshFinished() { pbLoading.setVisibility(View.GONE); if (layoutManagerSavedState != null) { recyclerView.getLayoutManager().onRestoreInstanceState(layoutManagerSavedState); layoutManagerSavedState = null; } } }); } /** * Updates the current RSS-View * @param context */ public void UpdateCurrentRssView(Context context) { Log.v(TAG, "UpdateCurrentRssView"); AsyncTaskHelper.StartAsyncTask(new UpdateCurrentRssViewTask(context)); } public RecyclerView getRecyclerView() { return recyclerView; } public LinearLayoutManager getLayoutManager() { if (recyclerView == null) return null; return (LinearLayoutManager) recyclerView.getLayoutManager(); } private class UpdateCurrentRssViewTask extends AsyncTask<Void, Void, List<RssItem>> { private Context context; private SORT_DIRECTION sortDirection; public UpdateCurrentRssViewTask(Context context) { this.context = context; } @Override protected void onPreExecute() { pbLoading.setVisibility(View.VISIBLE); tvNoItemsAvailable.setVisibility(View.GONE); sortDirection = getSortDirection(context); super.onPreExecute(); } @Override protected List<RssItem> doInBackground(Void... urls) { DatabaseConnectionOrm dbConn = new DatabaseConnectionOrm(context); SharedPreferences mPrefs = PreferenceManager.getDefaultSharedPreferences(context); boolean onlyUnreadItems = mPrefs.getBoolean(SettingsActivity.CB_SHOWONLYUNREAD_STRING, false); boolean onlyStarredItems = false; if (idFolder != null) if (idFolder == SubscriptionExpandableListAdapter.SPECIAL_FOLDERS.ALL_STARRED_ITEMS.getValue()) onlyStarredItems = true; String sqlSelectStatement = null; if (idFeed != null) sqlSelectStatement = dbConn.getAllItemsIdsForFeedSQL(idFeed, onlyUnreadItems, onlyStarredItems, sortDirection); else if (idFolder != null) { if (idFolder == SubscriptionExpandableListAdapter.SPECIAL_FOLDERS.ALL_STARRED_ITEMS.getValue()) onlyUnreadItems = false; sqlSelectStatement = dbConn.getAllItemsIdsForFolderSQL(idFolder, onlyUnreadItems, sortDirection); } if (sqlSelectStatement != null) { int index = sqlSelectStatement.indexOf("ORDER BY"); if (index == -1) { index = sqlSelectStatement.length(); } sqlSelectStatement = new StringBuilder(sqlSelectStatement) .insert(index, " GROUP BY " + RssItemDao.Properties.Fingerprint.columnName + " ") .toString(); dbConn.insertIntoRssCurrentViewTable(sqlSelectStatement); } StopWatch sw = new StopWatch(); sw.start(); List<RssItem> items = dbConn.getCurrentRssItemView(0); sw.stop(); Log.v(TAG, "Time needed (init loading): " + sw.toString()); return items; } @Override protected void onPostExecute(List<RssItem> rssItem) { try { NewsListRecyclerAdapter nra = ((NewsListRecyclerAdapter) recyclerView.getAdapter()); if (nra == null) { nra = new NewsListRecyclerAdapter(getActivity(), recyclerView, (PodcastFragmentActivity) getActivity()); recyclerView.setAdapter(nra); } nra.updateAdapterData(rssItem); pbLoading.setVisibility(View.GONE); if (nra.getItemCount() <= 0) { tvNoItemsAvailable.setVisibility(View.VISIBLE); } else { tvNoItemsAvailable.setVisibility(View.GONE); } recyclerView.scrollToPosition(0); } catch (Exception ex) { ex.printStackTrace(); } } } public static SORT_DIRECTION getSortDirection(Context context) { return NewsDetailActivity.getSortDirectionFromSettings(context); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_newsreader_detail, container, false); ButterKnife.bind(this, rootView); recyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false)); recyclerView.setItemAnimator(new DefaultItemAnimator()); ItemTouchHelper itemTouchHelper = new ItemTouchHelper(new NewsReaderItemTouchHelperCallback()); itemTouchHelper.attachToRecyclerView(recyclerView); recyclerView.addItemDecoration(new DividerItemDecoration(getActivity())); swipeRefresh.setColorSchemeColors(accentColor); swipeRefresh.setOnRefreshListener((SwipeRefreshLayout.OnRefreshListener) getActivity()); recyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() { GestureDetectorCompat detector = new GestureDetectorCompat(getActivity(), new RecyclerViewOnGestureListener()); @Override public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) { detector.onTouchEvent(e); return false; } @Override public void onTouchEvent(RecyclerView rv, MotionEvent e) { } @Override public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { } }); return rootView; } private class RecyclerViewOnGestureListener extends GestureDetector.SimpleOnGestureListener { @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { if (mMarkAsReadWhileScrollingEnabled && (e2.getY() - e1.getY()) < 0) { // (distance < 0) => scroll up handleMarkAsReadScrollEvent(); } return super.onScroll(e1, e2, distanceX, distanceY); } } @Override public void onInflate(Context context, AttributeSet attrs, Bundle savedInstanceState) { super.onInflate(context, attrs, savedInstanceState); TypedArray a = context.obtainStyledAttributes(attrs, new int[] { R.attr.markasreadDrawable, R.attr.starredDrawable, R.attr.colorAccent }); markAsReadDrawable = a.getDrawable(0); starredDrawable = a.getDrawable(1); accentColor = a.getColor(2, ContextCompat.getColor(context, R.color.owncloudBlueLight)); a.recycle(); } // TODO: somehow always cancel item out animation private class NewsReaderItemTouchHelperCallback extends ItemTouchHelper.SimpleCallback { public NewsReaderItemTouchHelperCallback() { super(0, ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT); } @Override public float getSwipeThreshold(RecyclerView.ViewHolder viewHolder) { return 0.25f; } @Override public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) { return false; } @Override public void onSwiped(final RecyclerView.ViewHolder viewHolder, final int direction) { final NewsListRecyclerAdapter adapter = (NewsListRecyclerAdapter) recyclerView.getAdapter(); if (direction == ItemTouchHelper.LEFT) { adapter.toggleReadStateOfItem((ViewHolder) viewHolder); } else if (direction == ItemTouchHelper.RIGHT) { adapter.toggleStarredStateOfItem((ViewHolder) viewHolder); //adapter.toggleReadStateOfItem((ViewHolder) viewHolder); } // Hack to reset view, see https://code.google.com/p/android/issues/detail?id=175798 recyclerView.removeView(viewHolder.itemView); } @Override public void onChildDraw(Canvas c, RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) { super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive); // swipeRefresh cancels swiping left/right when accidentally moving in the y direction; swipeRefresh.setEnabled(!isCurrentlyActive); if (isCurrentlyActive) { Rect viewRect = new Rect(); viewHolder.itemView.getDrawingRect(viewRect); float fractionMoved = Math.abs(dX / viewHolder.itemView.getMeasuredWidth()); Drawable drawable; if (dX < 0) { drawable = markAsReadDrawable; viewRect.left = (int) dX + viewRect.right; } else { drawable = starredDrawable; viewRect.right = (int) dX - viewRect.left; } if (fractionMoved > getSwipeThreshold(viewHolder)) drawable.setState(new int[] { android.R.attr.state_above_anchor }); else drawable.setState(new int[] { -android.R.attr.state_above_anchor }); viewRect.offset(0, viewHolder.itemView.getTop()); drawable.setBounds(viewRect); drawable.draw(c); } } } @Override public void onViewStateRestored(Bundle savedInstanceState) { if (savedInstanceState != null) layoutManagerSavedState = savedInstanceState.getParcelable(LAYOUT_MANAGER_STATE); super.onViewStateRestored(savedInstanceState); } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putParcelable(LAYOUT_MANAGER_STATE, getLayoutManager().onSaveInstanceState()); } public int getFirstVisibleScrollPosition() { LinearLayoutManager layoutManager = ((LinearLayoutManager) recyclerView.getLayoutManager()); return layoutManager.findFirstVisibleItemPosition(); } }