Java tutorial
/* * Copyright 2015 Udacity, 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.jpventura.alexandria; import android.app.Activity; import android.content.Context; import android.content.Intent; import android.database.Cursor; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.LoaderManager; import android.support.v4.content.CursorLoader; import android.text.Editable; import android.text.TextWatcher; import android.util.Patterns; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.EditText; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; import com.jpventura.alexandria.data.AlexandriaContract; import com.jpventura.alexandria.services.BookService; import com.jpventura.alexandria.services.DownloadImage; public class AddBook extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> { private static final String TAG = "INTENT_TO_SCAN_ACTIVITY"; private EditText ean; private final int LOADER_ID = 1; private View rootView; private final String EAN_CONTENT = "eanContent"; private static final String SCAN_FORMAT = "scanFormat"; private static final String SCAN_CONTENTS = "scanContents"; private String mScanFormat = "Format:"; private String mScanContents = "Contents:"; public AddBook() { } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); if (ean != null) { outState.putString(EAN_CONTENT, ean.getText().toString()); } } @Override public View onCreateView(final LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { rootView = inflater.inflate(R.layout.fragment_add_book, container, false); ean = (EditText) rootView.findViewById(R.id.ean); ean.addTextChangedListener(new TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { //no need } @Override public void onTextChanged(CharSequence s, int start, int before, int count) { //no need } @Override public void afterTextChanged(Editable s) { String ean = s.toString(); //catch isbn10 numbers if (ean.length() == 10 && !ean.startsWith("978")) { ean = "978" + ean; } if (ean.length() < 13) { clearFields(); return; } //Once we have an ISBN, start a book intent Intent bookIntent = new Intent(getActivity(), BookService.class); bookIntent.putExtra(BookService.EAN, ean); bookIntent.setAction(BookService.FETCH_BOOK); getActivity().startService(bookIntent); AddBook.this.restartLoader(); } }); rootView.findViewById(R.id.scan_button).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // This is the callback method that the system will invoke when your button is // clicked. You might do this by launching another app or by including the //functionality directly in this app. // Hint: Use a Try/Catch block to handle the Intent dispatch gracefully, if you // are using an external app. //when you're done, remove the toast below. Context context = getActivity(); CharSequence text = "This button should let you scan a book for its barcode!"; int duration = Toast.LENGTH_SHORT; Toast toast = Toast.makeText(context, text, duration); toast.show(); } }); rootView.findViewById(R.id.save_button).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { ean.setText(""); } }); rootView.findViewById(R.id.delete_button).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent bookIntent = new Intent(getActivity(), BookService.class); bookIntent.putExtra(BookService.EAN, ean.getText().toString()); bookIntent.setAction(BookService.DELETE_BOOK); getActivity().startService(bookIntent); ean.setText(""); } }); if (savedInstanceState != null) { ean.setText(savedInstanceState.getString(EAN_CONTENT)); ean.setHint(""); } return rootView; } private void restartLoader() { getLoaderManager().restartLoader(LOADER_ID, null, this); } @Override public android.support.v4.content.Loader<Cursor> onCreateLoader(int id, Bundle args) { if (ean.getText().length() == 0) { return null; } String eanStr = ean.getText().toString(); if (eanStr.length() == 10 && !eanStr.startsWith("978")) { eanStr = "978" + eanStr; } return new CursorLoader(getActivity(), AlexandriaContract.BookEntry.buildFullBookUri(Long.parseLong(eanStr)), null, null, null, null); } @Override public void onLoadFinished(android.support.v4.content.Loader<Cursor> loader, Cursor data) { if (!data.moveToFirst()) { return; } String bookTitle = data.getString(data.getColumnIndex(AlexandriaContract.BookEntry.TITLE)); ((TextView) rootView.findViewById(R.id.bookTitle)).setText(bookTitle); String bookSubTitle = data.getString(data.getColumnIndex(AlexandriaContract.BookEntry.SUBTITLE)); ((TextView) rootView.findViewById(R.id.bookSubTitle)).setText(bookSubTitle); String authors = data.getString(data.getColumnIndex(AlexandriaContract.AuthorEntry.AUTHOR)); String[] authorsArr = authors.split(","); ((TextView) rootView.findViewById(R.id.authors)).setLines(authorsArr.length); ((TextView) rootView.findViewById(R.id.authors)).setText(authors.replace(",", "\n")); String imgUrl = data.getString(data.getColumnIndex(AlexandriaContract.BookEntry.IMAGE_URL)); if (Patterns.WEB_URL.matcher(imgUrl).matches()) { new DownloadImage((ImageView) rootView.findViewById(R.id.bookCover)).execute(imgUrl); rootView.findViewById(R.id.bookCover).setVisibility(View.VISIBLE); } String categories = data.getString(data.getColumnIndex(AlexandriaContract.CategoryEntry.CATEGORY)); ((TextView) rootView.findViewById(R.id.categories)).setText(categories); rootView.findViewById(R.id.save_button).setVisibility(View.VISIBLE); rootView.findViewById(R.id.delete_button).setVisibility(View.VISIBLE); } @Override public void onLoaderReset(android.support.v4.content.Loader<Cursor> loader) { } private void clearFields() { ((TextView) rootView.findViewById(R.id.bookTitle)).setText(""); ((TextView) rootView.findViewById(R.id.bookSubTitle)).setText(""); ((TextView) rootView.findViewById(R.id.authors)).setText(""); ((TextView) rootView.findViewById(R.id.categories)).setText(""); rootView.findViewById(R.id.bookCover).setVisibility(View.INVISIBLE); rootView.findViewById(R.id.save_button).setVisibility(View.INVISIBLE); rootView.findViewById(R.id.delete_button).setVisibility(View.INVISIBLE); } @Override public void onAttach(Activity activity) { super.onAttach(activity); activity.setTitle(R.string.scan); } }