use a service as packet receiver

Author: oly-nittka

AndroidManifest.xml

@@ -10,7 +10,6 @@
     <uses-permission android:name="android.permission.INTERNET"/>
 
     <application
-        android:name=".AppMain" 
         android:icon="@drawable/netpowerctrl"
         android:label="@string/app_name" android:allowBackup="true">
         <activity
@@ -64,6 +63,13 @@
 	          android:name="android.appwidget.provider"
 	          android:resource="@xml/appwidget_provider" />
 		</receiver>
+		
+        <service 
+            android:label="@string/app_name"
+            android:icon="@drawable/netpowerctrl"
+            android:name=".NetpowerctrlService"
+            android:permission="android.permission.INTERNET">
+        </service>
 
      </application>
 

src/oly/netpowerctrl/AppMain.java

@@ -43,12 +43,13 @@ public class DeviceControl extends Activity implements OnClickListener {
 	public void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
 
-        ((AppMain)getApplicationContext()).maybeStartDiscoveryThreads(this);
+		Intent it = new Intent(this, NetpowerctrlService.class);
+		startService(it);
 
 		buttons = new ArrayList<CompoundButton>();
 
 		device = null;
-		Intent it = getIntent();
+		it = getIntent();
 		if (it != null) {
 			Bundle extra = it.getExtras();
 			if (extra != null) {
@@ -98,7 +99,6 @@ public void onCreate(Bundle savedInstanceState) {
 			ll.addView(cb, lp);
 			buttons.add(cb);
 		}
-		
 	}
 
 

src/oly/netpowerctrl/DeviceControl.java

@@ -83,6 +83,8 @@ public boolean onPreferenceChange(Preference preference, Object newValue) {
 
 		        getPreferenceManager().getSharedPreferences()
 		          .edit().putInt(SharedPrefs.PREF_RECVPORT, port);
+		        
+		        DeviceQuery.restartDiscovery(self);  // port may have changed
 				return true;
 			}
 		});

src/oly/netpowerctrl/DevicePreferences.java

@@ -12,8 +12,10 @@
 
 import android.app.Activity;
 import android.content.Context;
+import android.content.Intent;
 import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
+import android.support.v4.content.LocalBroadcastManager;
 import android.widget.Toast;
 
 public class DeviceQuery {
@@ -106,4 +108,9 @@ public static ArrayList<Integer> getAllReceivePorts(Context context) {
 		return new ArrayList<Integer>(ports);
 	}
 
+	public static void restartDiscovery(Context ctx) {
+		Intent it = new Intent(DiscoveryThread.BROADCAST_RESTART_DISCOVERY);
+        LocalBroadcastManager.getInstance(ctx).sendBroadcast(it);
+	}
+	
 }

src/oly/netpowerctrl/DeviceQuery.java

@@ -4,23 +4,24 @@
 import java.net.DatagramPacket;
 import java.net.DatagramSocket;
 
-import android.app.Activity;
+import android.content.Context;
 import android.content.Intent;
 import android.support.v4.content.LocalBroadcastManager;
 import android.widget.Toast;
 
 public class DiscoveryThread extends Thread {
 
 	public static String BROADCAST_DEVICE_DISCOVERED = "com.nittka.netpowerctrl.DEVICE_DISCOVERED";
+	public static String BROADCAST_RESTART_DISCOVERY = "com.nittka.netpowerctrl.RESTART_DISCOVERY";
 
 	int recv_port;
-	Activity activity;
+	Context ctx;
 	boolean keep_running;
 	DatagramSocket socket;
 
-	public DiscoveryThread(int port, Activity act) {
+	public DiscoveryThread(int port, Context context) {
 		recv_port = port;
-		activity = act;
+		ctx = context;
 		socket = null;
 	}
 
@@ -40,14 +41,10 @@ public void run() {
 				socket.close();
 			} catch (final IOException e) {
 				if (keep_running) { // no message if we were interrupt()ed
-					activity.runOnUiThread(new Runnable() {
-					    public void run() {
-					    	String msg = String.format(activity.getResources().getString(R.string.error_listen_thread_exception), recv_port);
-					    	msg += e.getLocalizedMessage();
-					    	if (recv_port < 1024) msg += activity.getResources().getString(R.string.error_port_lt_1024);
-					    	Toast.makeText(activity, msg, Toast.LENGTH_LONG).show();
-					    }
-					});
+			    	String msg = String.format(ctx.getResources().getString(R.string.error_listen_thread_exception), recv_port);
+			    	msg += e.getLocalizedMessage();
+			    	if (recv_port < 1024) msg += ctx.getResources().getString(R.string.error_port_lt_1024);
+			    	Toast.makeText(ctx, msg, Toast.LENGTH_LONG).show();
 				}
 				break;
 			}
@@ -73,18 +70,14 @@ public void parsePacket(final String message, int recevied_port) {
 			// error packet received
 			String desc;
 			if (msg[2].trim().equals("NoPass"))
-				desc = activity.getResources().getString(R.string.error_nopass);
+				desc = ctx.getResources().getString(R.string.error_nopass);
 			else desc = msg[2];
-			final String error = activity.getResources().getString(R.string.error_packet_received) + desc;
-			activity.runOnUiThread(new Runnable() {
-			    public void run() {
-			    	Toast.makeText(activity, error, Toast.LENGTH_LONG).show();
-			    }
-			});
+			String error = ctx.getResources().getString(R.string.error_packet_received) + desc;
+	    	Toast.makeText(ctx, error, Toast.LENGTH_LONG).show();
 			return;
 		}
 
-		final DeviceInfo di = new DeviceInfo(activity);
+		final DeviceInfo di = new DeviceInfo(ctx);
 		di.DeviceName = msg[1].trim();
 		di.HostName = msg[2];
 		di.MacAddress = msg[5];
@@ -103,13 +96,8 @@ public void run() {
 			di.Outlets.add(oi);
 		}
 
-		activity.runOnUiThread(new Runnable() {
-			public void run() {
-				Intent it = new Intent(BROADCAST_DEVICE_DISCOVERED);
-				it.putExtra("device_info", di);
-		        LocalBroadcastManager.getInstance(activity).sendBroadcast(it);
-			}
-		});
-		
+		Intent it = new Intent(BROADCAST_DEVICE_DISCOVERED);
+		it.putExtra("device_info", di);
+        LocalBroadcastManager.getInstance(ctx).sendBroadcast(it);
 	}
 }

src/oly/netpowerctrl/DiscoveryThread.java

@@ -59,8 +59,6 @@ public void onCreate(Bundle savedInstanceState) {
     	adpDiscoveredDevices = new DeviceListAdapter(this, alDiscoveredDevices);
   		lvDiscoveredDevices.setAdapter(adpDiscoveredDevices);
 
-        ReadConfiguredDevices();
-
         lvConfiguredDevices.setOnItemClickListener(this);
         lvDiscoveredDevices.setOnItemClickListener(this);
 
@@ -69,7 +67,6 @@ public void onCreate(Bundle savedInstanceState) {
 
         adpConfiguredDevices.setDeviceConfigureEvent(this);
         adpDiscoveredDevices.setDeviceConfigureEvent(this);
-        
     }
 
 
@@ -83,6 +80,9 @@ protected void onResume() {
     	IntentFilter itf= new IntentFilter(DiscoveryThread.BROADCAST_DEVICE_DISCOVERED);
         LocalBroadcastManager.getInstance(this).registerReceiver(onDeviceDiscovered, itf);
 
+		Intent it = new Intent(this, NetpowerctrlService.class);
+		startService(it);
+        
     	DeviceQuery.sendBroadcastQuery(this);
     }
 
@@ -161,12 +161,11 @@ public void ReadConfiguredDevices() {
     	alConfiguredDevices = SharedPrefs.ReadConfiguredDevices(this);
     	adpConfiguredDevices.setDevices(alConfiguredDevices);
         adpConfiguredDevices.getFilter().filter("");
-        ((AppMain)getApplicationContext()).restartDiscoveryThreads(this);
     }
 
     public void SaveConfiguredDevices() {
     	SharedPrefs.SaveConfiguredDevices(alConfiguredDevices, this);
-        ((AppMain)getApplicationContext()).restartDiscoveryThreads(this);
+        DeviceQuery.restartDiscovery(this);  // ports may have changed
     }
 
   	@Override

src/oly/netpowerctrl/NetpowerctrlActivity.java

@@ -0,0 +1,68 @@
+package oly.netpowerctrl;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import android.app.Service;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.IBinder;
+import android.support.v4.content.LocalBroadcastManager;
+
+public class NetpowerctrlService extends Service {
+
+	public static String BROADCAST_PORTS_CHANGED = "com.nittka.netpowerctrl.DEVICE_DISCOVERED";
+	List<DiscoveryThread> discoveryThreads;
+	
+	@Override
+	public void onCreate() {
+		//android.os.Debug.waitForDebugger();
+        discoveryThreads = new ArrayList<DiscoveryThread>();
+    	IntentFilter itf= new IntentFilter(DiscoveryThread.BROADCAST_RESTART_DISCOVERY);
+        LocalBroadcastManager.getInstance(this).registerReceiver(onConfigChanged, itf);
+	}
+
+	@Override
+	public IBinder onBind(Intent intent) {
+		// not needed, we use broadcasts
+		return null;
+	}
+
+	@Override
+	public int onStartCommand(Intent intent, int flags, int startId) {
+	    startDiscoveryThreads();
+	    return START_STICKY;
+	}
+	
+    public void startDiscoveryThreads() {
+    	// only start if not yet running
+    	if (discoveryThreads.size() == 0) {
+	    	for (int port: DeviceQuery.getAllReceivePorts(this)) {
+	        	DiscoveryThread thr = new DiscoveryThread(port, this);
+	        	thr.start();
+	        	discoveryThreads.add(thr);
+	        }
+    	}
+    	// give the threads a chance to start
+    	try {Thread.sleep(100);} catch (InterruptedException e) {}
+	}
+	
+    public void restartDiscoveryThreads() {
+    	for (DiscoveryThread thr: discoveryThreads)
+    		thr.interrupt();
+    	discoveryThreads.clear();
+    	// socket needs minimal time to really go away
+    	try {Thread.sleep(100);} catch (InterruptedException e) {}
+    	startDiscoveryThreads();
+	}
+	
+	private BroadcastReceiver onConfigChanged= new BroadcastReceiver() {
+		@Override
+	    public void onReceive(Context context, Intent intent) {
+			restartDiscoveryThreads();
+		}
+	};
+    
+}