以下是图书馆应用。在当前状态下，应用程序只能搜索单个单词。像＆＃34;哈利波特＆＃34;没有结果。我被告知要使用URLEncoder，但我尝试过，甚至没有用。以下是我的java文件。＆＃39;
MainActivity.java
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Bundle;
import android.app.LoaderManager;
import android.app.LoaderManager.LoaderCallbacks;
import android.content.Loader;
import android.support.v7.app.AppCompatActivity;
import android.text.TextUtils;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.Toast;
import com.google.android.gms.appindexing.Action;
import com.google.android.gms.appindexing.AppIndex;
import com.google.android.gms.appindexing.Thing;
import com.google.android.gms.common.api.GoogleApiClient;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity implements LoaderCallbacks<List<Books>>, SearchView.OnQueryTextListener {
LoaderManager loaderManager;
String mQuery;
SearchView mSearchView;
MenuItem mMenuSearchItem;
private static final String LOG_TAG = MainActivity.class.getName();
private static final String GOOGLE_REQUEST_URL = "https://www.googleapis.com/books/v1/volumes?maxResults=40&q=";
private String url = GOOGLE_REQUEST_URL + "android";
private static final int BOOK_LOADER_ID = 1;
private BookAdapter adapter;
/**
* ATTENTION: This was auto-generated to implement the App Indexing API.
* See https://g.co/AppIndexing/AndroidStudio for more information.
*/
private GoogleApiClient client;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView bookListView = (ListView) findViewById(R.id.list);
adapter = new BookAdapter(this, new ArrayList<Books>());
bookListView.setAdapter(adapter);
loaderManager = getLoaderManager();
loaderManager.initLoader(BOOK_LOADER_ID, null, this);
bookListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
Books currentBook = adapter.getItem(position);
Uri bookUri = Uri.parse(currentBook.getUrl());
Intent websiteIntent = new Intent(Intent.ACTION_VIEW, bookUri);
startActivity(websiteIntent);
}
});
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
}
public boolean isOnline() {
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
return netInfo != null && netInfo.isConnectedOrConnecting();
}
@Override
public boolean onQueryTextSubmit(String query) {
if(isOnline()){
url = GOOGLE_REQUEST_URL + query;
loaderManager.restartLoader(BOOK_LOADER_ID, null, this);
}else{
Toast.makeText(this, "No Internet Connection Found!", Toast.LENGTH_LONG).show();
}
return false;
}
@Override
public boolean onQueryTextChange(String newText) {
mQuery = newText;
return false;
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.options_menu, menu);
mMenuSearchItem = menu.findItem(R.id.menu_search);
mSearchView = (SearchView) menu.findItem(R.id.menu_search).getActionView();
if (mSearchView != null) {
mSearchView.setIconifiedByDefault(false);
mSearchView.setOnQueryTextListener(this);
mSearchView.setOnQueryTextFocusChangeListener(new View.OnFocusChangeListener() {
@Override
public void onFocusChange(View view, boolean queryTextFocused) {
if (!queryTextFocused) {
if (TextUtils.isEmpty(mQuery))
adapter.clear();
}
}
});
}
return true;
}
@Override
public Loader<List<Books>> onCreateLoader(int i, Bundle bundle) {
return new BookLoader(this, url);
}
@Override
public void onLoadFinished(Loader<List<Books>> loader, List<Books> books) {
adapter.clear();
if (books != null && !books.isEmpty()) {
adapter.addAll(books);
}
}
@Override
public void onLoaderReset(Loader<List<Books>> loader) {
adapter.clear();
}
/**
* ATTENTION: This was auto-generated to implement the App Indexing API.
* See https://g.co/AppIndexing/AndroidStudio for more information.
*/
public Action getIndexApiAction() {
Thing object = new Thing.Builder()
.setName("Main Page") // TODO: Define a title for the content shown.
// TODO: Make sure this auto-generated URL is correct.
.setUrl(Uri.parse("http://[ENTER-YOUR-URL-HERE]"))
.build();
return new Action.Builder(Action.TYPE_VIEW)
.setObject(object)
.setActionStatus(Action.STATUS_TYPE_COMPLETED)
.build();
}
@Override
public void onStart() {
super.onStart();
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
client.connect();
AppIndex.AppIndexApi.start(client, getIndexApiAction());
}
@Override
public void onStop() {
super.onStop();
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
AppIndex.AppIndexApi.end(client, getIndexApiAction());
client.disconnect();
}
BookUtils.java
import android.text.TextUtils;
import android.util.Log;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;
public final class BookUtils {
private static final String LOG_TAG = BookUtils.class.getSimpleName();
private BookUtils() {}
public static List<Books> fetchBookData(String requestUrl) {
URL url = createUrl(requestUrl);
String jsonResponse = null;
try {jsonResponse = makeHttpRequest(url);}
catch (IOException e) {Log.e(LOG_TAG, "Problem making the HTTP request.", e);}
List<Books> books = extractFeatureFromJson(jsonResponse);
return books;
}
private static URL createUrl(String stringUrl) {
URL url = null;
try {url = new URL(stringUrl);}
catch (MalformedURLException e) {Log.e(LOG_TAG, "Problem building the URL ", e);}
return url;
}
private static String makeHttpRequest(URL url) throws IOException {
String jsonResponse = "";
if (url == null) {return jsonResponse;}
HttpURLConnection urlConnection = null;
InputStream inputStream = null;
try {
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setReadTimeout(10000);
urlConnection.setConnectTimeout(15000);
urlConnection.setRequestMethod("GET");
urlConnection.connect();
if (urlConnection.getResponseCode() == 200) {
inputStream = urlConnection.getInputStream();
jsonResponse = readFromStream(inputStream);
} else {Log.e(LOG_TAG, "Error response code: " + urlConnection.getResponseCode());}
}
catch (IOException e) {Log.e(LOG_TAG, "Problem retrieving the book JSON results.", e);}
finally {
if (urlConnection != null) {urlConnection.disconnect();}
if (inputStream != null) {inputStream.close();}
}
return jsonResponse;
}
private static String readFromStream(InputStream inputStream) throws IOException {
StringBuilder output = new StringBuilder();
if (inputStream != null) {
InputStreamReader inputStreamReader = new InputStreamReader(inputStream, Charset.forName("UTF-8"));
BufferedReader reader = new BufferedReader(inputStreamReader);
String line = reader.readLine();
while (line != null) {
output.append(line);
line = reader.readLine();
}
}
return output.toString();
}
private static List<Books> extractFeatureFromJson(String bookJSON) {
if (TextUtils.isEmpty(bookJSON)) {return null;}
List<Books> books = new ArrayList<>();
try {
JSONObject jsonResponse = new JSONObject(bookJSON);
JSONArray booksArray = jsonResponse.getJSONArray("items");
for (int i = 0; i < booksArray.length(); i++) {
JSONObject currentBook = booksArray.getJSONObject(i);
JSONObject volumeInfo = currentBook.getJSONObject("volumeInfo");
JSONArray authorsArray = volumeInfo.getJSONArray("authors");
String title = "", publisher = "", publishedDate = "", language = "", pageCount = "", printType = "", maturityRating = "", authors = "";
if(volumeInfo.has("title")){
language = volumeInfo.getString("language");
}
for (int j = 0; j < authorsArray.length(); j++) {
if (volumeInfo.has("authors")){
authors = authorsArray.getString(j);
}
}
if(volumeInfo.has("publisher")){
publisher = volumeInfo.getString("publisher");
}
if(volumeInfo.has("publishedDate")){
publishedDate = volumeInfo.getString("publishedDate");
}
if(volumeInfo.has("language")){
language = volumeInfo.getString("language");
}
if(volumeInfo.has("pageCount")){
pageCount = volumeInfo.getString("pageCount");
}
if(volumeInfo.has("printType")){
printType = volumeInfo.getString("printType");
}
if(volumeInfo.has("maturityRating")){
maturityRating = volumeInfo.getString("maturityRating");
}
Books book = new Books(title, authors, publisher, publishedDate, language, pageCount, printType, maturityRating);
books.add(book);
}
}
catch (JSONException e) {Log.e("QueryUtils", "Problem parsing the book JSON results", e);}
return books;
}
}
Books.java
public class Books {
private String mTitle;
private String mAuthors;
private String mPublisher;
private String mPublishingDate;
private String mLanguage;
private String mCount;
private String mPrintType;
private String mMaturityRating;
private String mURL;
public Books(String title, String authors, String publisher, String publishingDate, String language, String count, String printType, String maturityRating) {
mTitle = title;
mAuthors = authors;
mPublisher = publisher;
mPublishingDate = publishingDate;
mLanguage = language;
mCount = count;
mPrintType = printType;
mMaturityRating = maturityRating;
}
public String getTitle() {return mTitle;}
public String getAuthors(){return mAuthors;}
public String getPublisher(){return mPublisher;}
public String getPublishedDate(){return mPublishingDate;}
public String getLanguage(){return mLanguage;}
public String getCount(){return mCount;}
public String getPrintType(){return mPrintType;}
public String getMaturityRating(){return mMaturityRating;}
public String getUrl() {return mURL;}
}
BookLoader.java
import android.content.AsyncTaskLoader;
import android.content.Context;
import java.util.List;
public class BookLoader extends AsyncTaskLoader<List<Books>> {
private static final String LOG_TAG = BookLoader.class.getName();
private String mUrl;
public BookLoader(Context context, String url) {
super(context);
mUrl = url;
}
@Override
protected void onStartLoading() {forceLoad();}
@Override
public List<Books> loadInBackground() {
if (mUrl == null) {return null;}
List<Books> books = BookUtils.fetchBookData(mUrl);
return books;
}
}
BookAdapter.java
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import java.util.List;
public class BookAdapter extends ArrayAdapter<Books> {
public BookAdapter(Context context, List<Books> books) {
super(context, 0, books);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View listItemView = convertView;
if (listItemView == null) {listItemView = LayoutInflater.from(getContext()).inflate(R.layout.book_list_item, parent, false);}
Books currentBook = getItem(position);
TextView title = (TextView) listItemView.findViewById(R.id.book_title);
title.setText(currentBook.getTitle());
TextView authors = (TextView) listItemView.findViewById(R.id.book_author);
authors.setText(currentBook.getAuthors());
TextView publisher = (TextView) listItemView.findViewById(R.id.book_publisher);
publisher.setText(currentBook.getPublisher());
TextView publishingDate = (TextView) listItemView.findViewById(R.id.book_publishing_date);
publishingDate.setText(currentBook.getPublishedDate());
TextView language = (TextView) listItemView.findViewById(R.id.book_language);
language.setText(currentBook.getLanguage());
TextView pageCount = (TextView) listItemView.findViewById(R.id.book_page_count);
pageCount.setText(currentBook.getCount());
TextView printType = (TextView) listItemView.findViewById(R.id.book_print_type);
printType.setText(currentBook.getPrintType());
TextView maturityRating = (TextView) listItemView.findViewById(R.id.book_maturity_rating);
maturityRating.setText(currentBook.getMaturityRating());
return listItemView;
}
}
在我的onQueryTextSubmit方法中，我尝试将url = GOOGLE_REQUEST_URL + query;替换为：
Uri.Builder uriBuilder = Uri.parse(GOOGLE_REQUEST_URL).buildUpon().appendQueryParameter("q", query);
url = uriBuilder.toString();
但它没有用。