Java tutorial
/* * Copyright 2015 Google Inc. All rights reserved. * * 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 com.google.samples.apps.iosched.map; import com.google.samples.apps.iosched.R; import com.google.samples.apps.iosched.map.util.SingleSessionLoader; import com.google.samples.apps.iosched.map.util.OverviewSessionLoader; import com.google.samples.apps.iosched.map.util.MarkerModel; import com.google.samples.apps.iosched.map.util.SessionLoader; import com.google.samples.apps.iosched.model.ScheduleHelper; import com.google.samples.apps.iosched.util.MapUtils; import com.google.samples.apps.iosched.util.TimeUtils; import com.google.samples.apps.iosched.util.UIUtils; import android.app.Activity; import android.app.Fragment; import android.app.LoaderManager; import android.content.Context; import android.content.Loader; import android.content.res.Resources; import android.database.Cursor; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Rect; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.content.res.ResourcesCompat; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.TextView; /** * Displays information about the map. * This includes a list of sessions that are directly loaded by this fragment. */ public abstract class MapInfoFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> { private static final int QUERY_TOKEN_SESSION_ROOM = 0x1; private static final int QUERY_TOKEN_SUBTITLE = 0x2; private static final String QUERY_ARG_ROOMID = "roomid"; private static final String QUERY_ARG_ROOMTITLE = "roomtitle"; private static final String QUERY_ARG_ROOMTYPE = "roomicon"; protected TextView mTitle; protected TextView mSubtitle; protected ImageView mIcon; protected RecyclerView mList; protected Callback mCallback = sDummyCallback; private static Callback sDummyCallback = new Callback() { @Override public void onInfoSizeChanged(int left, int top, int right, int bottom) { } @Override public void onSessionClicked(String id) { } }; @Override public void onAttach(Activity activity) { super.onAttach(activity); if (!(activity instanceof Callback)) { throw new ClassCastException("Activity must implement fragment's callback."); } mCallback = (Callback) activity; } @Override public void onDetach() { super.onDetach(); mCallback = sDummyCallback; } @Nullable @Override public abstract View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState); @Nullable public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState, int layout) { View root = inflater.inflate(layout, container, false); mTitle = (TextView) root.findViewById(R.id.map_info_title); mSubtitle = (TextView) root.findViewById(R.id.map_info_subtitle); mIcon = (ImageView) root.findViewById(R.id.map_info_icon); mIcon.setColorFilter(getResources().getColor(R.color.my_schedule_icon_default)); mList = (RecyclerView) root.findViewById(R.id.map_info_list); final Context context = mList.getContext(); mList.addItemDecoration(new DividerDecoration(context)); mList.setLayoutManager(new LinearLayoutManager(context)); return root; } @Override public Loader<Cursor> onCreateLoader(int id, Bundle args) { if (id != QUERY_TOKEN_SESSION_ROOM && id != QUERY_TOKEN_SUBTITLE) { return null; } final long time = TimeUtils.getCurrentTime(getActivity()); final String roomId = args.getString(QUERY_ARG_ROOMID); final String roomTitle = args.getString(QUERY_ARG_ROOMTITLE); final int roomType = args.getInt(QUERY_ARG_ROOMTYPE); if (id == QUERY_TOKEN_SESSION_ROOM) { return new OverviewSessionLoader(getActivity(), roomId, roomTitle, roomType, time); } else if (id == QUERY_TOKEN_SUBTITLE) { return new SingleSessionLoader(getActivity(), roomId, roomTitle, roomType); } return null; } @Override public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) { if (getActivity() == null) { return; } switch (loader.getId()) { case QUERY_TOKEN_SESSION_ROOM: { SessionLoader sessionLoader = (SessionLoader) loader; showSessionList(sessionLoader.getRoomTitle(), sessionLoader.getRoomType(), cursor); break; } case QUERY_TOKEN_SUBTITLE: { SessionLoader sessionLoader = (SessionLoader) loader; showSessionSubtitle(sessionLoader.getRoomTitle(), sessionLoader.getRoomType(), cursor); } } } /** * Creates a new instance depending of the form factor of the device. * For tablets, creates an {@link com.google.samples.apps.iosched.map.InlineInfoFragment}, * for other form factors a {@link com.google.samples.apps.iosched.map.SlideableInfoFragment}. * * @see com.google.samples.apps.iosched.util.UIUtils#isTablet(android.content.Context) */ public static MapInfoFragment newInstace(Context c) { if (UIUtils.isTablet(c)) { return InlineInfoFragment.newInstance(); } else { return SlideableInfoFragment.newInstance(); } } private void showSessionList(String roomTitle, int roomType, Cursor sessions) { if (sessions == null || sessions.isAfterLast()) { onSessionLoadingFailed(roomTitle, roomType); return; } onSessionsLoaded(roomTitle, roomType, sessions); mList.setAdapter(new SessionAdapter(getActivity(), sessions, MapUtils.hasInfoSessionListIcons(roomType), mOnClickListener)); } private void showSessionSubtitle(String roomTitle, int roomType, Cursor sessions) { if (sessions == null || sessions.isAfterLast()) { onSessionLoadingFailed(roomTitle, roomType); return; } sessions.moveToFirst(); final String title = roomTitle; final String subtitle = sessions.getString(SingleSessionLoader.Query.SESSION_ABSTRACT); setHeader(MapUtils.getRoomIcon(roomType), title, subtitle); mList.setVisibility(View.GONE); onRoomSubtitleLoaded(title, roomType, subtitle); } /** * Called when the subtitle has been loaded for a room. */ protected void onRoomSubtitleLoaded(String roomTitle, int roomType, String subTitle) { } /** * Called when the session list is about to be loaded for a new room. */ protected void onSessionListLoading(String roomId, String roomTitle) { // No default behavior } /** * Prepares and starts a SessionLoader for the specified query token. */ private void loadSessions(String roomId, String roomTitle, int roomType, int queryToken) { setHeader(MapUtils.getRoomIcon(roomType), roomTitle, null); onSessionListLoading(roomId, roomTitle); // Load the following sessions for this room LoaderManager lm = getLoaderManager(); Bundle args = new Bundle(); args.putString(QUERY_ARG_ROOMID, roomId); args.putString(QUERY_ARG_ROOMTITLE, roomTitle); args.putInt(QUERY_ARG_ROOMTYPE, roomType); lm.restartLoader(queryToken, args, this); } /** * Called when the abstract of the first session in this room is to be used as the subtitle. */ public void showFirstSessionTitle(String roomId, String roomTitle, int roomType) { loadSessions(roomId, roomTitle, roomType, QUERY_TOKEN_SUBTITLE); } /** * Called when a session list is to be displayed and has to be loaded. */ public void showSessionList(String roomId, String roomTitle, int roomType) { loadSessions(roomId, roomTitle, roomType, QUERY_TOKEN_SESSION_ROOM); } protected void onSessionsLoaded(String roomTitle, int roomType, Cursor cursor) { setHeader(MapUtils.getRoomIcon(roomType), roomTitle, null); mList.setVisibility(View.VISIBLE); } protected void onSessionLoadingFailed(String roomTitle, int roomType) { setHeader(MapUtils.getRoomIcon(roomType), roomTitle, null); mList.setVisibility(View.GONE); } public void showVenue() { setHeader(MapUtils.getRoomIcon(MarkerModel.TYPE_VENUE), R.string.map_venue_name, R.string.map_venue_address); mList.setVisibility(View.GONE); } protected void setHeader(int icon, int title, int subTitle) { mIcon.setImageResource(icon); if (title != 0) { mTitle.setText(title); mTitle.setVisibility(View.VISIBLE); } else { mTitle.setVisibility(View.GONE); } if (subTitle != 0) { mSubtitle.setText(subTitle); mSubtitle.setVisibility(View.VISIBLE); } else { mSubtitle.setVisibility(View.GONE); } } private void setHeader(int icon, String title, String subTitle) { mIcon.setImageResource(icon); if (title != null && !title.isEmpty()) { mTitle.setText(title); mTitle.setVisibility(View.VISIBLE); } else { mTitle.setVisibility(View.GONE); } if (subTitle != null && !subTitle.isEmpty()) { mSubtitle.setText(subTitle); mSubtitle.setVisibility(View.VISIBLE); } else { mSubtitle.setVisibility(View.GONE); } } public void showTitleOnly(int roomType, String title) { setHeader(MapUtils.getRoomIcon(roomType), title, null); mList.setVisibility(View.GONE); } public abstract void hide(); public abstract boolean isExpanded(); public abstract void minimize(); @Override public void onLoaderReset(Loader<Cursor> loader) { } interface Callback { public void onInfoSizeChanged(int left, int top, int right, int bottom); public void onSessionClicked(String id); } private View.OnClickListener mOnClickListener = new View.OnClickListener() { @Override public void onClick(final View v) { String sessionId = (String) v.getTag(R.id.tag_session_id); if (sessionId != null) { mCallback.onSessionClicked(sessionId); } } }; private static class DividerDecoration extends RecyclerView.ItemDecoration { private final Paint mPaint = new Paint(); private final int mHeight; public DividerDecoration(Context context) { final Resources resources = context.getResources(); mPaint.setColor(ResourcesCompat.getColor(resources, R.color.divider, context.getTheme())); mHeight = resources.getDimensionPixelSize(R.dimen.divider_height); } @Override public void getItemOffsets(final Rect outRect, final View view, final RecyclerView parent, final RecyclerView.State state) { outRect.set(0, 0, 0, mHeight); } @Override public void onDraw(final Canvas c, final RecyclerView parent, final RecyclerView.State state) { int width = parent.getWidth(); for (int i = 0, count = parent.getChildCount(); i < count; i++) { View child = parent.getChildAt(i); int bottom = child.getBottom(); c.drawRect(0, bottom, width, bottom + mHeight, mPaint); } } } /** * Adapter that displays a list of sessions. * This includes its title, time slot and icon. */ private static class SessionAdapter extends RecyclerView.Adapter<ItemHolder> { private final StringBuilder mStringBuilder = new StringBuilder(); private final Context mContext; private final Cursor mCursor; private final boolean mDisplayIcons; private final View.OnClickListener mListener; public SessionAdapter(Context context, Cursor cursor, boolean displayIcons, View.OnClickListener listener) { mContext = context; mCursor = cursor; mDisplayIcons = displayIcons; mListener = listener; } public String getSessionIdAtPosition(int position) { if (mCursor.moveToPosition(position)) { return mCursor.getString(OverviewSessionLoader.Query.SESSION_ID); } else { return null; } } @Override public ItemHolder onCreateViewHolder(final ViewGroup parent, final int viewType) { final ItemHolder holder = new ItemHolder(LayoutInflater.from(mContext), parent); holder.image.setVisibility(mDisplayIcons ? View.VISIBLE : View.INVISIBLE); holder.itemView.setOnClickListener(mListener); return holder; } @Override public void onBindViewHolder(final ItemHolder holder, final int position) { mCursor.moveToPosition(position); final String title = mCursor.getString(OverviewSessionLoader.Query.SESSION_TITLE); final String sessionId = mCursor.getString(OverviewSessionLoader.Query.SESSION_ID); final long blockStart = mCursor.getLong(OverviewSessionLoader.Query.SESSION_START); final long blockEnd = mCursor.getLong(OverviewSessionLoader.Query.SESSION_END); final String sessionTag = mCursor.getString(OverviewSessionLoader.Query.SESSION_TAGS); final int sessionType = ScheduleHelper.detectSessionType(sessionTag); final String text = UIUtils.formatIntervalTimeString(blockStart, blockEnd, mStringBuilder, mContext); holder.itemView.setTag(R.id.tag_session_id, sessionId); holder.title.setText(title); holder.text.setText(text); if (mDisplayIcons) { holder.image.setImageResource(UIUtils.getSessionIcon(sessionType)); } } @Override public int getItemCount() { return mCursor.getCount(); } } private static class ItemHolder extends RecyclerView.ViewHolder { TextView title; TextView text; ImageView image; public ItemHolder(LayoutInflater inflater, ViewGroup parent) { super(inflater.inflate(R.layout.map_item_session, parent, false)); title = (TextView) itemView.findViewById(R.id.map_item_title); text = (TextView) itemView.findViewById(R.id.map_item_text); image = (ImageView) itemView.findViewById(R.id.map_item_image); } } }