Java tutorial
/* * Copyright 2016 Google Inc. * * 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.g11x.checklistapp; import android.content.Intent; import android.database.ContentObserver; import android.database.Cursor; import android.graphics.Paint; import android.net.Uri; import android.os.Bundle; import android.os.Handler; import android.support.v4.app.LoaderManager; import android.support.v4.content.CursorLoader; import android.support.v4.content.Loader; import android.support.v4.util.ArrayMap; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.View; import android.widget.CheckBox; import android.widget.TextView; import com.firebase.ui.database.FirebaseRecyclerAdapter; import com.g11x.checklistapp.data.ChecklistItem; import com.g11x.checklistapp.data.Database; import com.g11x.checklistapp.language.Language; import com.google.firebase.database.DatabaseReference; import com.google.firebase.database.FirebaseDatabase; public class ChecklistActivity extends NavigationActivity implements LoaderManager.LoaderCallbacks<Cursor> { private static final int LOADER_ID = 9001; private FirebaseRecyclerAdapter<ChecklistItem, ChecklistItemHolder> checklistAdapter; private Language language; private final ArrayMap<String, Boolean> isDoneMapping = new ArrayMap<>(); private ContentObserver checklistContentObserver = null; @Override protected int getNavDrawerItemIndex() { return NavigationActivity.NAVDRAWER_ITEM_CHECKLIST; } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_checklist); language = AppPreferences.getLanguageOverride(this); DatabaseReference databaseRef = FirebaseDatabase.getInstance().getReference().child("checklists") .child("basic"); RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerview_checklist); recyclerView.setHasFixedSize(true); LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this); recyclerView.setLayoutManager(linearLayoutManager); checklistAdapter = new FirebaseRecyclerAdapter<ChecklistItem, ChecklistItemHolder>(ChecklistItem.class, R.layout.view_checklist_item, ChecklistItemHolder.class, databaseRef) { @Override protected void populateViewHolder(final ChecklistItemHolder itemHolder, final ChecklistItem model, final int position) { Boolean isDone = isDoneMapping.get(model.getHash()); if (isDoneMapping.get(model.getHash()) == null) { isDone = false; } itemHolder.markDone(isDone); itemHolder.setText(model.getName(language)); itemHolder.setDbRef(getRef(position)); itemHolder.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent intent = new Intent(ChecklistActivity.this, ChecklistItemActivity.class); intent.putExtra("databaseRefUrl", itemHolder.databaseRefUrl); startActivity(intent); } }); final Boolean finalIsDone = isDone; itemHolder.setCheckBoxOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { model.setDone(getContentResolver(), !finalIsDone); } }); } }; recyclerView.setAdapter(checklistAdapter); getSupportLoaderManager().initLoader(LOADER_ID, null, this); } @Override public void onLanguageChange(Language newLanguage) { language = newLanguage; } @Override protected void onDestroy() { super.onDestroy(); checklistAdapter.cleanup(); } public static class ChecklistItemHolder extends RecyclerView.ViewHolder { final View view; String databaseRefUrl; public ChecklistItemHolder(View itemView) { super(itemView); view = itemView; } public void markDone(boolean done) { TextView textView = (TextView) view.findViewById(R.id.info_text); if (done) { textView.setPaintFlags(textView.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG); } else { textView.setPaintFlags(textView.getPaintFlags() & (~Paint.STRIKE_THRU_TEXT_FLAG)); } CheckBox checkBox = (CheckBox) view.findViewById(R.id.checkbox); checkBox.setChecked(done); } public void setText(String title) { TextView textView = (TextView) view.findViewById(R.id.info_text); textView.setText(title); } public void setDbRef(DatabaseReference reference) { databaseRefUrl = reference.toString(); } public void setOnClickListener(View.OnClickListener listener) { TextView textView = (TextView) view.findViewById(R.id.info_text); textView.setOnClickListener(listener); } void setCheckBoxOnClickListener(View.OnClickListener listener) { CheckBox checkBox = (CheckBox) view.findViewById(R.id.checkbox); checkBox.setOnClickListener(listener); } } @Override public Loader<Cursor> onCreateLoader(int id, Bundle args) { if (checklistContentObserver != null) { getContentResolver().unregisterContentObserver(checklistContentObserver); } checklistContentObserver = new ContentObserver(new Handler()) { @Override public void onChange(boolean selfChange) { getSupportLoaderManager().restartLoader(LOADER_ID, null, ChecklistActivity.this); super.onChange(selfChange); } @Override public void onChange(boolean selfChange, Uri uri) { getSupportLoaderManager().restartLoader(LOADER_ID, null, ChecklistActivity.this); super.onChange(selfChange, uri); } }; getContentResolver().registerContentObserver(Database.ChecklistItem.CONTENT_URI, true, checklistContentObserver); return new CursorLoader(ChecklistActivity.this, Database.ChecklistItem.CONTENT_URI, ChecklistItem.PROJECTION, null, null, null); } @Override public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) { while (cursor.moveToNext()) { isDoneMapping.put(cursor.getString(ChecklistItem.ITEM_HASH_COLUMN_INDEX), cursor.getInt(ChecklistItem.DONE_COLUMN_INDEX) != 0); } checklistAdapter.notifyDataSetChanged(); } @Override public void onLoaderReset(Loader<Cursor> loader) { // don't bother telling the adapter that data has changed, just leave it be with the stale // data. } }