Java tutorial
/* * Copyright (c) 2015 Ha Duy Trung * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package io.github.hidroh.materialistic; import android.content.Context; import android.os.Bundle; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.support.v4.app.DialogFragment; import android.support.v4.app.Fragment; import android.support.v4.widget.SwipeRefreshLayout; import android.support.v7.widget.RecyclerView; import android.text.TextUtils; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import java.lang.ref.WeakReference; import java.util.ArrayList; import java.util.Arrays; import javax.inject.Inject; import javax.inject.Named; import io.github.hidroh.materialistic.annotation.Synthetic; import io.github.hidroh.materialistic.data.Item; import io.github.hidroh.materialistic.data.ItemManager; import io.github.hidroh.materialistic.data.ResponseListener; import io.github.hidroh.materialistic.data.WebItem; import io.github.hidroh.materialistic.widget.CommentItemDecoration; import io.github.hidroh.materialistic.widget.ItemRecyclerViewAdapter; import io.github.hidroh.materialistic.widget.MultiPageItemRecyclerViewAdapter; import io.github.hidroh.materialistic.widget.SinglePageItemRecyclerViewAdapter; import io.github.hidroh.materialistic.widget.SnappyLinearLayoutManager; public class ItemFragment extends LazyLoadFragment implements Scrollable, Navigable { public static final String EXTRA_ITEM = ItemFragment.class.getName() + ".EXTRA_ITEM"; public static final String EXTRA_CACHE_MODE = ItemFragment.class.getName() + ".EXTRA_CACHE_MODE"; private static final String STATE_ITEM = "state:item"; private static final String STATE_ITEM_ID = "state:itemId"; private static final String STATE_ADAPTER_ITEMS = "state:adapterItems"; private static final String STATE_CACHE_MODE = "state:cacheMode"; private RecyclerView mRecyclerView; private View mEmptyView; private Item mItem; private String mItemId; @Inject @Named(ActivityModule.HN) ItemManager mItemManager; private SwipeRefreshLayout mSwipeRefreshLayout; private SinglePageItemRecyclerViewAdapter.SavedState mAdapterItems; private ItemRecyclerViewAdapter mAdapter; private KeyDelegate.RecyclerViewHelper mScrollableHelper; private @ItemManager.CacheMode int mCacheMode = ItemManager.MODE_DEFAULT; private final Preferences.Observable mPreferenceObservable = new Preferences.Observable(); private CommentItemDecoration mItemDecoration; @Override public void onAttach(Context context) { super.onAttach(context); mPreferenceObservable.subscribe(context, this::onPreferenceChanged, R.string.pref_comment_display, R.string.pref_max_lines, R.string.pref_username, R.string.pref_line_height, R.string.pref_color_code, R.string.pref_thread_indicator, R.string.pref_font, R.string.pref_text_size, R.string.pref_smooth_scroll); } @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setHasOptionsMenu(true); if (savedInstanceState != null) { mCacheMode = savedInstanceState.getInt(STATE_CACHE_MODE, ItemManager.MODE_DEFAULT); mItem = savedInstanceState.getParcelable(STATE_ITEM); mItemId = savedInstanceState.getString(STATE_ITEM_ID); mAdapterItems = savedInstanceState.getParcelable(STATE_ADAPTER_ITEMS); } else { mCacheMode = getArguments().getInt(EXTRA_CACHE_MODE, ItemManager.MODE_DEFAULT); WebItem item = getArguments().getParcelable(EXTRA_ITEM); if (item instanceof Item) { mItem = (Item) item; } mItemId = item != null ? item.getId() : null; } } @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable final Bundle savedInstanceState) { final View view = getLayoutInflater(savedInstanceState).inflate(R.layout.fragment_item, container, false); mEmptyView = view.findViewById(R.id.empty); mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view); mRecyclerView.setLayoutManager(new SnappyLinearLayoutManager(getActivity(), true)); mItemDecoration = new CommentItemDecoration(getActivity()); mRecyclerView.addItemDecoration(mItemDecoration); mSwipeRefreshLayout = (SwipeRefreshLayout) view.findViewById(R.id.swipe_layout); mSwipeRefreshLayout.setColorSchemeResources(R.color.white); mSwipeRefreshLayout.setProgressBackgroundColorSchemeResource(R.color.redA200); mSwipeRefreshLayout.setOnRefreshListener(() -> { if (TextUtils.isEmpty(mItemId)) { return; } mCacheMode = ItemManager.MODE_NETWORK; if (mAdapter != null) { mAdapter.setCacheMode(mCacheMode); } loadKidData(); }); return view; } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); mScrollableHelper = new KeyDelegate.RecyclerViewHelper(mRecyclerView, KeyDelegate.RecyclerViewHelper.SCROLL_ITEM); mScrollableHelper.smoothScrollEnabled(Preferences.smoothScrollEnabled(getActivity())); } @Override public boolean onOptionsItemSelected(MenuItem item) { if (item.getItemId() == R.id.menu_comments) { showPreferences(); return true; } return super.onOptionsItemSelected(item); } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putParcelable(STATE_ITEM, mItem); outState.putString(STATE_ITEM_ID, mItemId); outState.putParcelable(STATE_ADAPTER_ITEMS, mAdapterItems); outState.putInt(STATE_CACHE_MODE, mCacheMode); } @Override public void onDetach() { super.onDetach(); mRecyclerView.setAdapter(null); mPreferenceObservable.unsubscribe(getActivity()); } @Override public void scrollToTop() { mScrollableHelper.scrollToTop(); } @Override public boolean scrollToNext() { return mScrollableHelper.scrollToNext(); } @Override public boolean scrollToPrevious() { return mScrollableHelper.scrollToPrevious(); } @Override public void onNavigate(int direction) { if (mAdapter == null) { // no kids return; } mAdapter.getNextPosition(mScrollableHelper.getCurrentPosition(), direction, position -> mAdapter.lockBinding(mScrollableHelper.scrollToPosition(position))); } @Override protected void load() { if (mItem != null) { bindKidData(); } else if (!TextUtils.isEmpty(mItemId)) { loadKidData(); } } @Override protected void createOptionsMenu(Menu menu, MenuInflater inflater) { inflater.inflate(R.menu.menu_item_view, menu); } private void loadKidData() { mItemManager.getItem(mItemId, mCacheMode, new ItemResponseListener(this)); } void onItemLoaded(@Nullable Item item) { mSwipeRefreshLayout.setRefreshing(false); if (item != null) { mAdapterItems = null; mItem = item; notifyItemLoaded(item); bindKidData(); } } private void bindKidData() { if (mItem == null || mItem.getKidCount() == 0) { mEmptyView.setVisibility(View.VISIBLE); return; } String displayOption = Preferences.getCommentDisplayOption(getActivity()); if (Preferences.isSinglePage(getActivity(), displayOption)) { boolean autoExpand = Preferences.isAutoExpand(getActivity(), displayOption); // if collapsed or no saved state then start a fresh (adapter items all collapsed) if (!autoExpand || mAdapterItems == null) { mAdapterItems = new SinglePageItemRecyclerViewAdapter.SavedState( new ArrayList<>(Arrays.asList(mItem.getKidItems()))); } mAdapter = new SinglePageItemRecyclerViewAdapter(mItemManager, mAdapterItems, autoExpand); } else { mAdapter = new MultiPageItemRecyclerViewAdapter(mItemManager, mItem.getKidItems()); } mAdapter.setCacheMode(mCacheMode); mAdapter.initDisplayOptions(getActivity()); mRecyclerView.setAdapter(mAdapter); } private void onPreferenceChanged(int key, boolean contextChanged) { if (contextChanged || key == R.string.pref_comment_display) { load(); } else if (mAdapter != null) { mScrollableHelper.smoothScrollEnabled(Preferences.smoothScrollEnabled(getActivity())); mItemDecoration.setColorCodeEnabled(Preferences.colorCodeEnabled(getActivity())); mItemDecoration.setThreadIndicatorEnabled(Preferences.threadIndicatorEnabled(getActivity())); mAdapter.initDisplayOptions(getActivity()); mAdapter.notifyDataSetChanged(); } } private void showPreferences() { Bundle args = new Bundle(); args.putInt(PopupSettingsFragment.EXTRA_TITLE, R.string.font_options); args.putInt(PopupSettingsFragment.EXTRA_SUMMARY, R.string.pull_up_hint); args.putIntArray(PopupSettingsFragment.EXTRA_XML_PREFERENCES, new int[] { R.xml.preferences_font, R.xml.preferences_comments }); ((DialogFragment) Fragment.instantiate(getActivity(), PopupSettingsFragment.class.getName(), args)) .show(getFragmentManager(), PopupSettingsFragment.class.getName()); } private void notifyItemLoaded(@NonNull Item item) { if (getActivity() instanceof ItemChangedListener) { ((ItemChangedListener) getActivity()).onItemChanged(item); } } static class ItemResponseListener implements ResponseListener<Item> { private WeakReference<ItemFragment> mItemFragment; @Synthetic ItemResponseListener(ItemFragment itemFragment) { mItemFragment = new WeakReference<>(itemFragment); } @Override public void onResponse(@Nullable Item response) { if (mItemFragment.get() != null && mItemFragment.get().isAttached()) { mItemFragment.get().onItemLoaded(response); } } @Override public void onError(String errorMessage) { if (mItemFragment.get() != null && mItemFragment.get().isAttached()) { mItemFragment.get().onItemLoaded(null); } } } interface ItemChangedListener { void onItemChanged(@NonNull Item item); } }