Service : IntentService « Core Class « Android

1. Android
2. Core Class
3. IntentService

Service

  

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.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.Messenger;
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;

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.handler=new FeedHandler(this);
      
      Intent i=new Intent(this, FeedService.class);
      
      i.putExtra(FeedService.EXTRA_URL,
                 getIntent().getStringExtra(FEED_URL));
      i.putExtra(FeedService.EXTRA_MESSENGER,
                 new Messenger(state.handler));
      
      startService(i);
    }
    else {
      if (state.handler!=null) {
        state.handler.attach(this);
      }
      
      if (state.feed!=null) {
        setFeed(state.feed);
      }
    }
  }
  
  @Override
  public Object onRetainNonConfigurationInstance() {
    if (state.handler!=null) {
      state.handler.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;
    FeedHandler handler=null;
  }
  
  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);
    }
  }
  
  private static class FeedHandler extends Handler {
    FeedActivity activity=null;
    
    FeedHandler(FeedActivity activity) {
      attach(activity);
    }
    
    void attach(FeedActivity activity) {
      this.activity=activity;
    }
    
    void detach() {
      this.activity=null;
    }
    
    @Override
    public void handleMessage(Message msg) {
      if (msg.arg1==RESULT_OK) {
        activity.setFeed((RSSFeed)msg.obj);
      }
      else {
        activity.goBlooey((Exception)msg.obj);
      }
    }
  }
}



package apt.tutorial;

import android.app.Activity;
import android.app.IntentService;
import android.content.Intent;
import android.os.Message;
import android.os.Messenger;
import android.util.Log;
import org.mcsoxford.rss.RSSItem;
import org.mcsoxford.rss.RSSFeed;
import org.mcsoxford.rss.RSSReader;

public class FeedService extends IntentService {
  public static final String EXTRA_URL="apt.tutorial.EXTRA_URL";
  public static final String EXTRA_MESSENGER="apt.tutorial.EXTRA_MESSENGER";

  public FeedService() {
    super("FeedService");
  }
  
  @Override
  public void onHandleIntent(Intent i) {
    RSSReader reader=new RSSReader();
    Messenger messenger=(Messenger)i.getExtras().get(EXTRA_MESSENGER);
    Message msg=Message.obtain();
    
    try {
      RSSFeed result=reader.load(i.getStringExtra(EXTRA_URL));
      
      msg.arg1=Activity.RESULT_OK;
      msg.obj=result;
    }
    catch (Exception e) {
      Log.e("LunchList", "Exception parsing feed", e);
      msg.arg1=Activity.RESULT_CANCELED;
      msg.obj=e;
    }
    
    try {
      messenger.send(msg);
    }
    catch (Exception e) {
      Log.w("LunchList", "Exception sending results to activity", e);
    }
  }
}




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 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:layout_span="2"
    android:hint="Notes"
  />
  <EditText android:id="@+id/feed"
    android:layout_span="2"
    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>

   
    
  

Related examples in the same category