Access the Internet
/*
Welcome to the source code for Android Programming Tutorials (http://commonsware.com/AndTutorials)!
Specifically, this is for Version 3.2 and above of this book.
For the source code for older versions of this book, please
visit:
https://github.com/commonsguy/cw-andtutorials
All of the source code in this archive is licensed under the
Apache 2.0 license except as noted.
The names of the top-level directories roughly correspond to a
shortened form of the chapter titles. Since chapter numbers
change with every release, and since some samples are used by
multiple chapters, I am loathe to put chapter numbers in the
actual directory names.
If you wish to use this code, bear in mind a few things:
* The projects are set up to be built by Ant, not by Eclipse.
If you wish to use the code with Eclipse, you will need to
create a suitable Android Eclipse project and import the
code and other assets.
* You should delete build.xml from the project, then run
android update project -p ...
(where ... is the path to a project of interest)
on those projects you wish to use, so the build files are
updated for your Android SDK version.
*/
package apt.tutorial;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
public class DetailForm extends Activity {
EditText name=null;
EditText address=null;
EditText notes=null;
EditText feed=null;
RadioGroup types=null;
RestaurantHelper helper=null;
String restaurantId=null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.detail_form);
helper=new RestaurantHelper(this);
name=(EditText)findViewById(R.id.name);
address=(EditText)findViewById(R.id.addr);
notes=(EditText)findViewById(R.id.notes);
types=(RadioGroup)findViewById(R.id.types);
feed=(EditText)findViewById(R.id.feed);
Button save=(Button)findViewById(R.id.save);
save.setOnClickListener(onSave);
restaurantId=getIntent().getStringExtra(LunchList.ID_EXTRA);
if (restaurantId!=null) {
load();
}
}
@Override
public void onDestroy() {
super.onDestroy();
helper.close();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
new MenuInflater(this).inflate(R.menu.details_option, menu);
return(super.onCreateOptionsMenu(menu));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId()==R.id.feed) {
if (isNetworkAvailable()) {
Intent i=new Intent(this, FeedActivity.class);
i.putExtra(FeedActivity.FEED_URL, feed.getText().toString());
startActivity(i);
}
else {
Toast
.makeText(this, "Sorry, the Internet is not available",
Toast.LENGTH_LONG)
.show();
}
return(true);
}
return(super.onOptionsItemSelected(item));
}
private boolean isNetworkAvailable() {
ConnectivityManager cm=(ConnectivityManager)getSystemService(CONNECTIVITY_SERVICE);
NetworkInfo info=cm.getActiveNetworkInfo();
return(info!=null);
}
private void load() {
Cursor c=helper.getById(restaurantId);
c.moveToFirst();
name.setText(helper.getName(c));
address.setText(helper.getAddress(c));
notes.setText(helper.getNotes(c));
feed.setText(helper.getFeed(c));
if (helper.getType(c).equals("sit_down")) {
types.check(R.id.sit_down);
}
else if (helper.getType(c).equals("take_out")) {
types.check(R.id.take_out);
}
else {
types.check(R.id.delivery);
}
c.close();
}
private View.OnClickListener onSave=new View.OnClickListener() {
public void onClick(View v) {
String type=null;
switch (types.getCheckedRadioButtonId()) {
case R.id.sit_down:
type="sit_down";
break;
case R.id.take_out:
type="take_out";
break;
case R.id.delivery:
type="delivery";
break;
}
if (restaurantId==null) {
helper.insert(name.getText().toString(),
address.getText().toString(), type,
notes.getText().toString(),
feed.getText().toString());
}
else {
helper.update(restaurantId, name.getText().toString(),
address.getText().toString(), type,
notes.getText().toString(),
feed.getText().toString());
}
finish();
}
};
}
package apt.tutorial;
import android.app.Activity;
import android.os.Bundle;
import android.preference.PreferenceActivity;
public class EditPreferences extends PreferenceActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.preferences);
}
}
package apt.tutorial;
import android.app.AlertDialog;
import android.app.ListActivity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
import org.mcsoxford.rss.RSSItem;
import org.mcsoxford.rss.RSSFeed;
import org.mcsoxford.rss.RSSReader;
public class FeedActivity extends ListActivity {
public static final String FEED_URL="apt.tutorial.FEED_URL";
private InstanceState state=null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
state=(InstanceState)getLastNonConfigurationInstance();
if (state==null) {
state=new InstanceState();
state.task=new FeedTask(this);
state.task.execute(getIntent().getStringExtra(FEED_URL));
}
else {
if (state.task!=null) {
state.task.attach(this);
}
if (state.feed!=null) {
setFeed(state.feed);
}
}
}
@Override
public Object onRetainNonConfigurationInstance() {
if (state.task!=null) {
state.task.detach();
}
return(state);
}
private void setFeed(RSSFeed feed) {
state.feed=feed;
setListAdapter(new FeedAdapter(feed));
}
private void goBlooey(Throwable t) {
AlertDialog.Builder builder=new AlertDialog.Builder(this);
builder
.setTitle("Exception!")
.setMessage(t.toString())
.setPositiveButton("OK", null)
.show();
}
private static class InstanceState {
RSSFeed feed=null;
FeedTask task=null;
}
private static class FeedTask extends AsyncTask<String, Void, RSSFeed> {
private RSSReader reader=new RSSReader();
private Exception e=null;
private FeedActivity activity=null;
FeedTask(FeedActivity activity) {
attach(activity);
}
void attach(FeedActivity activity) {
this.activity=activity;
}
void detach() {
this.activity=null;
}
@Override
public RSSFeed doInBackground(String... urls) {
RSSFeed result=null;
try {
result=reader.load(urls[0]);
}
catch (Exception e) {
this.e=e;
}
return(result);
}
@Override
public void onPostExecute(RSSFeed feed) {
if (e==null) {
activity.setFeed(feed);
}
else {
Log.e("LunchList", "Exception parsing feed", e);
activity.goBlooey(e);
}
}
}
private class FeedAdapter extends BaseAdapter {
RSSFeed feed=null;
FeedAdapter(RSSFeed feed) {
super();
this.feed=feed;
}
@Override
public int getCount() {
return(feed.getItems().size());
}
@Override
public Object getItem(int position) {
return(feed.getItems().get(position));
}
@Override
public long getItemId(int position) {
return(position);
}
@Override
public View getView(int position, View convertView,
ViewGroup parent) {
View row=convertView;
if (row==null) {
LayoutInflater inflater=getLayoutInflater();
row=inflater.inflate(android.R.layout.simple_list_item_1,
parent, false);
}
RSSItem item=(RSSItem)getItem(position);
((TextView)row).setText(item.getTitle());
return(row);
}
}
}
package apt.tutorial;
import android.app.ListActivity;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.LayoutInflater;
import android.widget.AdapterView;
import android.widget.CursorAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
public class LunchList extends ListActivity {
public final static String ID_EXTRA="apt.tutorial._ID";
Cursor model=null;
RestaurantAdapter adapter=null;
RestaurantHelper helper=null;
SharedPreferences prefs=null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
helper=new RestaurantHelper(this);
prefs=PreferenceManager.getDefaultSharedPreferences(this);
initList();
prefs.registerOnSharedPreferenceChangeListener(prefListener);
}
@Override
public void onDestroy() {
super.onDestroy();
helper.close();
}
@Override
public void onListItemClick(ListView list, View view,
int position, long id) {
Intent i=new Intent(LunchList.this, DetailForm.class);
i.putExtra(ID_EXTRA, String.valueOf(id));
startActivity(i);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
new MenuInflater(this).inflate(R.menu.option, menu);
return(super.onCreateOptionsMenu(menu));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId()==R.id.add) {
startActivity(new Intent(LunchList.this, DetailForm.class));
return(true);
}
else if (item.getItemId()==R.id.prefs) {
startActivity(new Intent(this, EditPreferences.class));
return(true);
}
return(super.onOptionsItemSelected(item));
}
private void initList() {
if (model!=null) {
stopManagingCursor(model);
model.close();
}
model=helper.getAll(prefs.getString("sort_order", "name"));
startManagingCursor(model);
adapter=new RestaurantAdapter(model);
setListAdapter(adapter);
}
private SharedPreferences.OnSharedPreferenceChangeListener prefListener=
new SharedPreferences.OnSharedPreferenceChangeListener() {
public void onSharedPreferenceChanged(SharedPreferences sharedPrefs,
String key) {
if (key.equals("sort_order")) {
initList();
}
}
};
class RestaurantAdapter extends CursorAdapter {
RestaurantAdapter(Cursor c) {
super(LunchList.this, c);
}
@Override
public void bindView(View row, Context ctxt,
Cursor c) {
RestaurantHolder holder=(RestaurantHolder)row.getTag();
holder.populateFrom(c, helper);
}
@Override
public View newView(Context ctxt, Cursor c,
ViewGroup parent) {
LayoutInflater inflater=getLayoutInflater();
View row=inflater.inflate(R.layout.row, parent, false);
RestaurantHolder holder=new RestaurantHolder(row);
row.setTag(holder);
return(row);
}
}
static class RestaurantHolder {
private TextView name=null;
private TextView address=null;
private ImageView icon=null;
RestaurantHolder(View row) {
name=(TextView)row.findViewById(R.id.title);
address=(TextView)row.findViewById(R.id.address);
icon=(ImageView)row.findViewById(R.id.icon);
}
void populateFrom(Cursor c, RestaurantHelper helper) {
name.setText(helper.getName(c));
address.setText(helper.getAddress(c));
if (helper.getType(c).equals("sit_down")) {
icon.setImageResource(R.drawable.ball_red);
}
else if (helper.getType(c).equals("take_out")) {
icon.setImageResource(R.drawable.ball_yellow);
}
else {
icon.setImageResource(R.drawable.ball_green);
}
}
}
}
package apt.tutorial;
import android.content.Context;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteQueryBuilder;
class RestaurantHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME="lunchlist.db";
private static final int SCHEMA_VERSION=2;
public RestaurantHelper(Context context) {
super(context, DATABASE_NAME, null, SCHEMA_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE restaurants (_id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, address TEXT, type TEXT, notes TEXT, feed TEXT);");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("ALTER TABLE restaurants ADD COLUMN feed TEXT");
}
public Cursor getAll(String orderBy) {
return(getReadableDatabase()
.rawQuery("SELECT _id, name, address, type, notes, feed FROM restaurants ORDER BY "+orderBy,
null));
}
public Cursor getById(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, name, address, type, notes, feed FROM restaurants WHERE _ID=?",
args));
}
public void insert(String name, String address,
String type, String notes,
String feed) {
ContentValues cv=new ContentValues();
cv.put("name", name);
cv.put("address", address);
cv.put("type", type);
cv.put("notes", notes);
cv.put("feed", feed);
getWritableDatabase().insert("restaurants", "name", cv);
}
public void update(String id, String name, String address,
String type, String notes, String feed) {
ContentValues cv=new ContentValues();
String[] args={id};
cv.put("name", name);
cv.put("address", address);
cv.put("type", type);
cv.put("notes", notes);
cv.put("feed", feed);
getWritableDatabase().update("restaurants", cv, "_ID=?",
args);
}
public String getName(Cursor c) {
return(c.getString(1));
}
public String getAddress(Cursor c) {
return(c.getString(2));
}
public String getType(Cursor c) {
return(c.getString(3));
}
public String getNotes(Cursor c) {
return(c.getString(4));
}
public String getFeed(Cursor c) {
return(c.getString(5));
}
}
//res\xml\preferences.xml
<PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android">
<ListPreference
android:key="sort_order"
android:title="Sort Order"
android:summary="Choose the order the list uses"
android:entries="@array/sort_names"
android:entryValues="@array/sort_clauses"
android:dialogTitle="Choose a sort order" />
</PreferenceScreen>
//res\values\arrays.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string-array name="sort_names">
<item>By Name, Ascending</item>
<item>By Name, Descending</item>
<item>By Type</item>
<item>By Address, Ascending</item>
<item>By Address, Descending</item>
</string-array>
<string-array name="sort_clauses">
<item>name ASC</item>
<item>name DESC</item>
<item>type, name ASC</item>
<item>address ASC</item>
<item>address DESC</item>
</string-array>
</resources>
//res\values\strings.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">LunchList</string>
</resources>
//res\menu\details_option.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/feed"
android:title="RSS Feed"
android:icon="@drawable/ic_menu_friendslist"
/>
</menu>
//res\menu\option.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/add"
android:title="Add"
android:icon="@drawable/ic_menu_add"
/>
<item android:id="@+id/prefs"
android:title="Settings"
android:icon="@drawable/ic_menu_preferences"
/>
</menu>
//res\layout-land\detail_form.xml
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:stretchColumns="2"
>
<TableRow>
<TextView android:text="Name:" />
<EditText android:id="@+id/name"
android:layout_span="2"
/>
</TableRow>
<TableRow>
<TextView android:text="Address:" />
<EditText android:id="@+id/addr"
android:layout_span="2"
/>
</TableRow>
<TableRow>
<TextView android:text="Type:" />
<RadioGroup android:id="@+id/types">
<RadioButton android:id="@+id/take_out"
android:text="Take-Out"
/>
<RadioButton android:id="@+id/sit_down"
android:text="Sit-Down"
/>
<RadioButton android:id="@+id/delivery"
android:text="Delivery"
/>
</RadioGroup>
<LinearLayout android:orientation="vertical">
<EditText android:id="@+id/notes"
android:singleLine="false"
android:gravity="top"
android:lines="2"
android:scrollHorizontally="false"
android:maxLines="2"
android:maxWidth="140sp"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:hint="Notes"
/>
<EditText android:id="@+id/feed"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:hint="Feed URL"
/>
<Button android:id="@+id/save"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Save"
/>
</LinearLayout>
</TableRow>
</TableLayout>
//res\layout\detail_form.xml
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:stretchColumns="1"
>
<TableRow>
<TextView android:text="Name:" />
<EditText android:id="@+id/name" />
</TableRow>
<TableRow>
<TextView android:text="Address:" />
<EditText android:id="@+id/addr" />
</TableRow>
<TableRow>
<TextView android:text="Type:" />
<RadioGroup android:id="@+id/types">
<RadioButton android:id="@+id/take_out"
android:text="Take-Out"
/>
<RadioButton android:id="@+id/sit_down"
android:text="Sit-Down"
/>
<RadioButton android:id="@+id/delivery"
android:text="Delivery"
/>
</RadioGroup>
</TableRow>
<EditText android:id="@+id/notes"
android:singleLine="false"
android:gravity="top"
android:lines="2"
android:scrollHorizontally="false"
android:maxLines="2"
android:maxWidth="200sp"
android:hint="Notes"
/>
<EditText android:id="@+id/feed"
android:hint="Feed URL"
/>
<Button android:id="@+id/save"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Save"
/>
</TableLayout>
//res\layout\main.xml
<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
//res\layout\row.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="4dip"
>
<ImageView android:id="@+id/icon"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_alignParentTop="true"
android:layout_alignParentBottom="true"
android:layout_marginRight="4dip"
/>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
>
<TextView android:id="@+id/title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_vertical"
android:textStyle="bold"
android:singleLine="true"
android:ellipsize="end"
/>
<TextView android:id="@+id/address"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_vertical"
android:singleLine="true"
android:ellipsize="end"
/>
</LinearLayout>
</LinearLayout>