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Clear all list item on button click

I have created simple chatting application and it contains some ListView which handles all chat messages, but every ListView is defined in another class. I want to clear my list items from Clear Chat from an overflow menu, which is present in main activity. How can I achieve this?
Here is my main activity called WiFiServiceDiscoveryActivity:
public class WiFiServiceDiscoveryActivity extends AppCompatActivity implements
DeviceClickListener, Handler.Callback, MessageTarget,
ConnectionInfoListener {
public static final String TAG = "wifidirectdemo";
// TXT RECORD properties
public static final String TXTRECORD_PROP_AVAILABLE = "available";
public static final String SERVICE_INSTANCE = " ";
public static final String SERVICE_REG_TYPE = "_presence._tcp";
public static final int MESSAGE_READ = 0x400 + 1;
public static final int MY_HANDLE = 0x400 + 2;
private WifiP2pManager manager;
static final int SERVER_PORT = 4545;
private final IntentFilter intentFilter = new IntentFilter();
private Channel channel;
private BroadcastReceiver receiver = null;
private WifiP2pDnsSdServiceRequest serviceRequest;
private Handler handler = new Handler(this);
private WiFiChatFragment chatFragment;
private WiFiDirectServicesList servicesList;
private TextView statusTxtView;
Toolbar toolbar;
private String friend;
private WiFiP2pService service;
WiFiChatFragment listView;
WiFiChatFragment.ChatMessageAdapter a;
public Handler getHandler() {
return handler;
}
public void setHandler(Handler handler) {
this.handler = handler;
}
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
toolbar=(Toolbar)findViewById(R.id.toolbar);
statusTxtView = (TextView) findViewById(R.id.status_text);
intentFilter.addAction(WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION);
intentFilter.addAction(WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION);
intentFilter
.addAction(WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION);
intentFilter
.addAction(WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION);
manager = (WifiP2pManager) getSystemService(Context.WIFI_P2P_SERVICE);
channel = manager.initialize(this, getMainLooper(), null);
startRegistrationAndDiscovery();
servicesList = new WiFiDirectServicesList();
getFragmentManager().beginTransaction()
.add(R.id.container_root, servicesList, "services").commit();
setSupportActionBar(toolbar);
}
#Override
protected void onRestart() {
Fragment frag = getFragmentManager().findFragmentByTag("services");
if (frag != null) {
getFragmentManager().beginTransaction().remove(frag).commit();
}
super.onRestart();
}
#Override
protected void onStop() {
if (manager != null && channel != null) {
manager.removeGroup(channel, new ActionListener() {
#Override
public void onFailure(int reasonCode) {
Log.d(TAG, "Disconnect failed. Reason :" + reasonCode);
}
#Override
public void onSuccess() {
}
});
}
super.onStop();
}
/**
* Registers a local service and then initiates a service discovery
*/
private void startRegistrationAndDiscovery() {
Map<String, String> record = new HashMap<String, String>();
record.put(TXTRECORD_PROP_AVAILABLE, "visible");
WifiP2pDnsSdServiceInfo service = WifiP2pDnsSdServiceInfo.newInstance(
SERVICE_INSTANCE, SERVICE_REG_TYPE, record);
manager.addLocalService(channel, service, new ActionListener() {
#Override
public void onSuccess() {
//appendStatus("Added Local Service");
}
#Override
public void onFailure(int error) {
// appendStatus("Failed to add a service");
}
});
discoverService();
}
private void discoverService() {
/*
* Register listeners for DNS-SD services. These are callbacks invoked
* by the system when a service is actually discovered.
*/
manager.setDnsSdResponseListeners(channel,
new DnsSdServiceResponseListener() {
#Override
public void onDnsSdServiceAvailable(String instanceName,
String registrationType, WifiP2pDevice srcDevice) {
// A service has been discovered. Is this our app?
if (instanceName.equalsIgnoreCase(SERVICE_INSTANCE)) {
// update the UI and add the item the discovered
// device.
WiFiDirectServicesList fragment = (WiFiDirectServicesList) getFragmentManager()
.findFragmentByTag("services");
if (fragment != null) {
WiFiDevicesAdapter adapter = ((WiFiDevicesAdapter) fragment
.getListAdapter());
service = new WiFiP2pService();
service.device = srcDevice;
service.instanceName = instanceName;
service.serviceRegistrationType = registrationType;
adapter.add(service);
adapter.notifyDataSetChanged();
Log.d(TAG, "onBonjourServiceAvailable "
+ instanceName);
}
}
}
}, new DnsSdTxtRecordListener() {
/**
* A new TXT record is available. Pick up the advertised
* buddy name.
*/
#Override
public void onDnsSdTxtRecordAvailable(
String fullDomainName, Map<String, String> record,
WifiP2pDevice device) {
Log.d(TAG,
device.deviceName + " is "
+ record.get(TXTRECORD_PROP_AVAILABLE));
}
});
// After attaching listeners, create a service request and initiate
// discovery.
serviceRequest = WifiP2pDnsSdServiceRequest.newInstance();
manager.addServiceRequest(channel, serviceRequest,
new ActionListener() {
#Override
public void onSuccess() {
// appendStatus("Added service discovery request");
}
#Override
public void onFailure(int arg0) {
appendStatus("Failed adding service discovery request");
}
});
manager.discoverServices(channel, new ActionListener() {
#Override
public void onSuccess() {
//appendStatus("Service discovery initiated");
}
#Override
public void onFailure(int arg0) {
appendStatus("Service discovery failed");
}
});
}
#Override
public void connectP2p(WiFiP2pService service) {
WifiP2pConfig config = new WifiP2pConfig();
config.deviceAddress = service.device.deviceAddress;
config.wps.setup = WpsInfo.PBC;
if (serviceRequest != null)
manager.removeServiceRequest(channel, serviceRequest,
new ActionListener() {
#Override
public void onSuccess() {
}
#Override
public void onFailure(int arg0) {
}
});
manager.connect(channel, config, new ActionListener() {
#Override
public void onSuccess() {
appendStatus("Connecting to service");
}
#Override
public void onFailure(int errorCode) {
appendStatus("Failed connecting to service");
}
});
}
#Override
public boolean handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
String readMessage = new String(readBuf, 0, msg.arg1);
Log.d(TAG, readMessage);
(chatFragment).pushMessage("Friend :" + readMessage);
break;
case MY_HANDLE:
Object obj = msg.obj;
(chatFragment).setChatManager((ChatManager) obj);
}
return true;
}
#Override
public void onResume() {
super.onResume();
receiver = new HomeActivity(manager, channel, this);
registerReceiver(receiver, intentFilter);
}
#Override
public void onPause() {
super.onPause();
unregisterReceiver(receiver);
}
#Override
public void onConnectionInfoAvailable(WifiP2pInfo p2pInfo) {
Thread handler = null;
if (p2pInfo.isGroupOwner) {
Log.d(TAG, "Connected as group owner");
try {
handler = new GroupOwnerSocketHandler(
((MessageTarget) this).getHandler());
handler.start();
} catch (IOException e) {
Log.d(TAG,
"Failed to create a server thread - " + e.getMessage());
return;
}
} else {
Log.d(TAG, "Connected as peer");
handler = new ClientSocketHandler(
((MessageTarget) this).getHandler(),
p2pInfo.groupOwnerAddress);
handler.start();
}
chatFragment = new WiFiChatFragment();
getFragmentManager().beginTransaction()
.replace(R.id.container_root, chatFragment).commit();
statusTxtView.setVisibility(View.GONE);
}
public void appendStatus(String status) {
String current = statusTxtView.getText().toString();
statusTxtView.setText(current + "\n" + status);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_settings:
Toast.makeText(this, "Settings selected", Toast.LENGTH_SHORT)
.show();
break;
case R.id.clean:
Toast.makeText(this, "Clear Chat", Toast.LENGTH_SHORT).show();
break;
default:
break;
}
return true;
}
}
And another class which has the ListView called WiFiChatFragment:
public class WiFiChatFragment extends Fragment {
private View view;
private ChatManager chatManager;
private TextView chatLine;
private ListView listView;
ChatMessageAdapter adapter = null;
private List<String> items = new ArrayList<String>();
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_chat, container, false);
chatLine = (TextView) view.findViewById(R.id.txtChatLine);
listView = (ListView) view.findViewById(android.R.id.list);
adapter = new ChatMessageAdapter(getActivity(), android.R.id.text1,
items);
listView.setAdapter(adapter);
view.findViewById(R.id.button1).setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View arg0) {
if (chatManager != null) {
chatManager.write(chatLine.getText().toString()
.getBytes());
pushMessage("Me: " + chatLine.getText().toString());
chatLine.setText("");
chatLine.clearFocus();
}
}
});
return view;
}
public interface MessageTarget {
public Handler getHandler();
}
public void setChatManager(ChatManager obj) {
chatManager = obj;
}
public void pushMessage(String readMessage) {
adapter.add(readMessage);
adapter.notifyDataSetChanged();
}
/**
* ArrayAdapter to manage chat messages.
*/
public class ChatMessageAdapter extends ArrayAdapter<String> {
List<String> messages = null;
public ChatMessageAdapter(Context context, int textViewResourceId,
List<String> items) {
super(context, textViewResourceId, items);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
if (v == null) {
LayoutInflater vi = (LayoutInflater) getActivity()
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(android.R.layout.simple_list_item_1, null);
}
String message = items.get(position);
if (message != null && !message.isEmpty()) {
TextView nameText = (TextView) v
.findViewById(android.R.id.text1);
if (nameText != null) {
nameText.setText(message);
if (message.startsWith("Me: ")) {
nameText.setBackgroundResource(R.drawable.bubble_b );
nameText.setTextAppearance(getActivity(),
R.style.normalText);
} else {
nameText.setBackgroundResource(R.drawable.bubble_a );
nameText.setTextAppearance(getActivity(),
R.style.boldText);
}
}
}
return v;
}
}
}

Hey Adesh you could do this when the overflow item is clicked:
Call setListAdapter() again. This time with an empty ArrayList.
Hope it helps !

Error: ViewPostImeInputStage ACTION_DOWN

I can't figure out why my onClick method for my buttons are not working. Everytime I click the button, my logcat says ViewPostImeInputStage Action_Down.
I appreciate any help!
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
BluetoothConnect fragment = new BluetoothConnect();
transaction.add(R.id.sample_content_fragment, fragment);
transaction.commit();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
And this is my fragment.
public class BluetoothConnect extends Fragment {
//For debugging purposes
private static final String TAG = "BluetoothConnect";
// Intent request codes
private static final int REQUEST_CONNECT_DEVICE_SECURE = 1;
private static final int REQUEST_CONNECT_DEVICE_INSECURE = 2;
private static final int REQUEST_ENABLE_BT = 3;
//Main buttons
private Button shareButton;
private Button listenButton;
private TextView test;
/**
* Name of the connected device
*/
private String mConnectedDeviceName = null;
/**
* Local Bluetooth adapter
*/
private BluetoothAdapter mBluetoothAdapter = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
//Get local Bluetooth adapter
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
//If the adapter is null, then Bluetooth is not supported
if (mBluetoothAdapter == null) {
FragmentActivity activity = getActivity();
Toast.makeText(activity, "Bluetooth is not available", Toast.LENGTH_LONG).show();
activity.finish();
}
}
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container,
#Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.activity_main, container, false);
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
listenButton = (Button) view.findViewById(R.id.listen);
shareButton = (Button) view.findViewById(R.id.share);
test = (TextView) view.findViewById(R.id.test);
}
#Override
public void onStart() {
super.onStart();
//If BT is not on, request that it be enabled
if (!mBluetoothAdapter.isEnabled()) {
Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
} else {
setupButtons();
}
}
#Override
public void onDestroy() {
super.onDestroy();
//Figure out what to do if we need to destroy
}
#Override public void onResume() {
super.onResume();
//figure out what to do if person pauses out of app
}
public void setupButtons() {
Log.d(TAG, "setupButtons()");
//Initialize the music buttons
listenButton.setOnClickListener(new ButtonOnClickListener("listen"));
Log.d(TAG, "finished listenButton");
shareButton.setOnClickListener(new ButtonOnClickListener("share"));
}
private class ButtonOnClickListener implements View.OnClickListener {
String type;
public ButtonOnClickListener(String button) {
Log.d(TAG, this.type);
this.type = button;
}
public void onClick(View view) {
if (this.type == "listen") {
listenMusic();
} else {
shareMusic();
}
}
}
private void ensureDiscoverable() {
if (mBluetoothAdapter.getScanMode() !=
BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
startActivity(discoverableIntent);
}
}
private void listenMusic() {
Log.d(TAG, "OMG ITS WORKING");
}
private void shareMusic() {
Log.d(TAG, "OMG ITS WORKING");
}
}
Thanks so much!

have a look here
https://stackoverflow.com/a/32016362/5281187
Wrap your layout over the one you already have

Textview click in listview [duplicate]

This question already has answers here:
Call Activity method from adapter
(9 answers)
Closed 8 years ago.
I have a textview in a listview on clicking which it should perform some activity. Currently,I am writing onClick of textview inside getView method of custom adapter class. On click of textview , I am trigerring a method in my Activity class . But that Activity has that variable value as NULL eventhough its already been initialised in onCreate of Activity. Here's my code:
Adapter class:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final int pos = position;
Item item = (Item) getItem(position);
TextView textView = (TextView) view
.findViewById(R.id.tv_song_title);
textView.setText(item.text);
textView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
MainActivity main = new MainActivity();
main.songPicked(pos); //calling act class method
}
});
Activity class:
private MusicService musicSrv;
public void songPicked(int position) { //method called
if (musicSrv!=null) //is null .Why??
{
musicSrv.setSong(position);
songName = musicSrv.playSong();
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
songAdt = new SongAdapter();
songAdt.setRows(rows);
songView.setAdapter(songAdt);
playMusic();
}
public void playMusic() {
if (playIntent == null) {
playIntent = new Intent(this, MusicService.class);
startService(playIntent);
bindService(playIntent, musicConnection, Context.BIND_AUTO_CREATE);
}
}
// connect to the service
private ServiceConnection musicConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
MusicBinder binder = (MusicBinder) service;
// get service
musicSrv = binder.getService();
// pass list
musicSrv.setList(songList);
musicBound = true;
Log.i("LEAKTEST", "Connected to instance " + this.toString());
}
#Override
public void onServiceDisconnected(ComponentName name) {
musicBound = false;
musicSrv = null;
}

Use listeners instead of passing the whole activity.
The main idea is
public interface SmthListener() {
void onSmthHappens(smthParams);
}
public class WhoNotify {
SmthListener mListener;
public WhoNotify(SmthListener listener) {
mListener = listener;
}
public void smthHappensInMyClass() {
mListener.onSmthHappens(smthParams);
}
}
public class WhoListene implements SmthListener {
#Override
public void onCreate(...) {
... new WhoNotify(this);
}
#Override
void onSmthHappens(smthParams) {
// do stuff;
}
}

Android: Execute http requests via Service

I have a trouble with getting Activity(Nullpointerexception) after that I have rotate screen and received callback from AsyncTask to update my views of the fragment. If I wont change orientation then everything is OK(but not all the time, sometimes this bug appears)
My main activity:
public class MainActivity extends SherlockFragmentActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.pager_layout);
fm = getSupportFragmentManager();
fm.addOnBackStackChangedListener(this);
session = new SessionManager(getApplicationContext());
if (session.isAuthorizated()) {
disableTabs();
FragmentTransaction ft = fm.beginTransaction();
if (session.termsAndConditions()) {
ft.replace(android.R.id.content, new TermsAndConditionsFragment(), "terms-and-conditions").commit();
}
}
} else {
enableTabs();
mTabsAdapter = new TabsAdapter(this, mViewPager);
mTabsAdapter.addTab(actionBar.newTab().setText("Log in"), LoginFragment.class, null);
mTabsAdapter.addTab(actionBar.newTab().setText("Calculator"), CalculatorFragment.class, null);
}
}
That`s my fragment:
public class TermsAndConditionsFragment extends SherlockFragment implements OnClickListener, OnTouchListener, OnEditorActionListener, ValueSelectedListener, AsyncUpdateViewsListener {
private static final String TAG = "TermsAndConditionsFragment";
private TermsAndConditionsManager termsAndConditionsM;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
prepareData();
}
public void prepareData() {
if (getSherlockActivity() == null)
Log.d(TAG, "Activity is null");
termsAndConditionsM = new TermsAndConditionsManager(getSherlockActivity().getApplicationContext());
termsAndConditions = termsAndConditionsM.getTermsAndConditions();
...
// some stuff
...
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
rootView = init(inflater, container);
return rootView;
}
private View init(LayoutInflater inflater, ViewGroup container) {
rootView = inflater.inflate(R.layout.fragment_terms_and_conditions, container, false);
//bla bla bla
return rootView;
}
public void updateTermsAndConditionsView() {
//update views here
}
#Override
public void onClick(View v) {
ft = fm.beginTransaction();
switch (v.getId()) {
case R.id.etHowMuch:
d = NumberPaymentsPickerFragment.newInstance(getSherlockActivity(), Integer.valueOf(howMuch.replace("£", "")), 0);
d.setValueSelectedListener(this);
d.show(getFragmentManager(), Const.HOW_MUCH);
break;
}
}
#Override
public void onValueSelected() {
Bundle args = new Bundle();
...
ExecuteServerTaskBackground task = new ExecuteServerTaskBackground(getSherlockActivity());
task.setAsyncUpdateViewsListener(this);
task.action = ServerAPI.GET_TERMS_AND_CONDITIONS;
task.args = args;
task.execute();
}
#Override
public void onUpdateViews() {
prepareData();
updateTermsAndConditionsView();
}
}
My AsyncTask with callback:
public class ExecuteServerTaskBackground extends AsyncTask<Void, Void, Void> {
private static final String TAG = "ExecuteServerTaskBackground";
Activity mActivity;
Context mContext;
private AsyncUpdateViewsListener callback;
public ExecuteServerTaskBackground(Activity activity) {
this.mActivity = activity;
this.mContext = activity.getApplicationContext();
}
public void setAsyncUpdateViewsListener(AsyncUpdateViewsListener listener) {
callback = listener;
}
#Override
protected Void doInBackground(Void... params) {
ServerAPI server = new ServerAPI(mContext);
if (!args.isEmpty())
msg = server.serverRequest(action, args);
else
msg = server.serverRequest(action, null);
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
callback.onUpdateViews();
}
}
Why does it behave so? How can I get activity correctly if I change orientation.
EDIT:
As I understand correctly nullpointer appears after orientation changed and asynctask executed due to wrong reference between asyctask and Activity. Recreated activity doesnt have this reference thats why when I receive callback I use wrong activity reference which isn`t exist anymore. But how can I save current activity reference?
EDIT:
I have decided to try realize my task throughout Service and that`s what I have done.
Activity:
public class MainFragment extends Fragment implements ServiceExecutorListener, OnClickListener {
private static final String TAG = MainFragment.class.getName();
Button btnSend, btnCheck;
TextView serviceStatus;
Intent intent;
Boolean bound = false;
ServiceConnection sConn;
RESTService service;
ProgressDialog pd = new ProgressDialog();
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setRetainInstance(true);
intent = new Intent(getActivity(), RESTService.class);
getActivity().startService(intent);
sConn = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName name, IBinder binder) {
Log.d(TAG, "MainFragment onServiceConnected");
service = ((RESTService.MyBinder) binder).getService();
service.registerListener(MainFragment.this);
if (service.taskIsDone())
serviceStatus.setText(service.getResult());
bound = true;
}
public void onServiceDisconnected(ComponentName name) {
Log.d(TAG, "MainFragment onServiceDisconnected");
bound = false;
}
};
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.main_fragment, container, false);
serviceStatus = (TextView) rootView.findViewById(R.id.tvServiceStatusValue);
btnSend = (Button) rootView.findViewById(R.id.btnSend);
btnCheck = (Button) rootView.findViewById(R.id.btnCheck);
btnSend.setOnClickListener(this);
btnCheck.setOnClickListener(this);
return rootView;
}
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnSend:
pd.show(getFragmentManager(), "ProgressDialog");
service.run(7);
service.run(2);
service.run(4);
break;
case R.id.btnCheck:
if (service != null)
serviceStatus.setText(String.valueOf(service.taskIsDone()) + service.getTasksCount());
break;
}
}
#Override
public void onStart() {
super.onStart();
Log.d(TAG, "Bind service");
getActivity().bindService(intent, sConn, 0);
}
#Override
public void onPause() {
super.onDestroy();
Log.d(TAG, "onDestroy: Unbind service");
if (!bound)
return;
getActivity().unbindService(sConn);
service.unregisterListener(this);
bound = false;
}
#Override
public void onComplete(String result) {
Log.d(TAG, "Task Completed");
pd.dismiss();
serviceStatus.setText(result);
}
}
Dialog:
public class ProgressDialog extends DialogFragment implements OnClickListener {
final String TAG = ProgressDialog.class.getName();
public Dialog onCreateDialog(Bundle savedInstanceState) {
setRetainInstance(true);
AlertDialog.Builder adb = new AlertDialog.Builder(getActivity())
.setTitle("Title!")
.setPositiveButton(R.string.yes, this)
.setNegativeButton(R.string.no, this)
.setNeutralButton(R.string.maybe, this)
.setCancelable(false)
.setMessage(R.string.message_text)
.setOnKeyListener(new OnKeyListener() {
#Override
public boolean onKey(DialogInterface dialog, int keyCode, KeyEvent event) {
return true;
}
});
return adb.create();
}
public void onClick(DialogInterface dialog, int which) {
int i = 0;
switch (which) {
case Dialog.BUTTON_POSITIVE:
i = R.string.yes;
break;
case Dialog.BUTTON_NEGATIVE:
i = R.string.no;
break;
case Dialog.BUTTON_NEUTRAL:
i = R.string.maybe;
break;
}
if (i > 0)
Log.d(TAG, "Dialog 2: " + getResources().getString(i));
}
public void onDismiss(DialogInterface dialog) {
Log.d(TAG, "Dialog 2: onDismiss");
// Fix to avoid simple dialog dismiss in orientation change
if ((getDialog() != null) && getRetainInstance())
getDialog().setDismissMessage(null);
super.onDestroyView();
}
public void onCancel(DialogInterface dialog) {
super.onCancel(dialog);
Log.d(TAG, "Dialog 2: onCancel");
}
}
Service:
public class RESTService extends Service {
final String TAG = RESTService.class.getName();
MyBinder binder = new MyBinder();
ArrayList<ServiceExecutorListener> listeners = new ArrayList<ServiceExecutorListener>();
Handler h = new Handler();
RequestManager mRequest;
ExecutorService es;
Object obj;
int time;
StringBuilder builder;
String result = null;
public void onCreate() {
super.onCreate();
Log.d(TAG, "RESTService onCreate");
es = Executors.newFixedThreadPool(1);
obj = new Object();
builder = new StringBuilder();
}
public void run(int time) {
RunRequest rr = new RunRequest(time);
es.execute(rr);
}
class RunRequest implements Runnable {
int time;
public RunRequest(int time) {
this.time = time;
Log.d(TAG, "RunRequest create");
}
public void run() {
Log.d(TAG, "RunRequest start, time = " + time);
try {
TimeUnit.SECONDS.sleep(time);
} catch (InterruptedException e) {
e.printStackTrace();
}
try {
Log.d(TAG, "RunRequest obj = " + obj.getClass());
} catch (NullPointerException e) {
Log.d(TAG, "RunRequest error, null pointer");
}
builder.append("result " + time + ", ");
result = builder.toString();
sendCallback();
}
}
private void sendCallback() {
h.post(new Runnable() {
#Override
public void run() {
for (ServiceExecutorListener listener : listeners)
listener.onComplete();
}
});
}
public boolean taskIsDone() {
if (result != null)
return true;
return false;
}
public String getResult() {
return result;
}
public void registerListener(ServiceExecutorListener listener) {
listeners.add(listener);
}
public void unregisterListener(ServiceExecutorListener listener) {
listeners.remove(listener);
}
public IBinder onBind(Intent intent) {
Log.d(TAG, "RESTService onBind");
return binder;
}
public boolean onUnbind(Intent intent) {
Log.d(TAG, "RESTService onUnbind");
return true;
}
public class MyBinder extends Binder {
public RESTService getService() {
return RESTService.this;
}
}
}

As you mention in your edit, the current Activity is destroyed and recreated on orientation change.
But how can I save current activity reference?
You shouldn't. The previous Activity is no longer valid. This will not only cause NPEs but also memory leaks because the AsyncTask might hold the reference to old Activity, maybe forever.
Solution is to use Loaders.

How to Show ListView Items in Tabs

In Contacts Tab, trying to fetch list of all Facebook Friends
In Month Tab, trying to fetch list of Facebook Friends those Birthdays in Current Month
In Week Tab, trying to fetch list of Facebook Friends those Birthdays in Current Week
I have written code for all and i am not getting any error while build and run my program, but i am not getting list of friends in any of the Tab.
Please let me know, where i am doing silly mistake...where i am missing..
TabSample.Java :-
public class TabSample extends TabActivity {
String response;
private static JSONArray jsonArray;
public static TabHost mTabHost;
private MyFacebook fb = MyFacebook.getInstance();
public static MyLocalDB db = null;
private BcReceiver bcr = null;
private BcReceiverAlarm bcra = null;
private PendingIntent mAlarmSender;
private boolean isAlarmSet;
private ProgressDialog busyDialog;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mAlarmSender = PendingIntent.getService(TabSample.this, 0, new Intent(
TabSample.this, BdRemService.class), 0);
setContentView(R.layout.main);
if (db == null) {
db = new MyLocalDB(this);
db.open();
}
if (!fb.isReady()) {
Log.v(TAG, "TabSample- initiating facebook");
fb.init(this);// after finishing, this will call loadContents itself
} else {
loadContents();
}
busyDialog = new ProgressDialog(this);
busyDialog.setIndeterminate(true);
busyDialog.setMessage("Refreshing");
Bundle extras = getIntent().getExtras();
if (extras == null) {
return;
}
response = getIntent().getStringExtra("FRIENDS");
try {
jsonArray = new JSONArray(response);
} catch (JSONException e) {
FacebookUtility.displayMessageBox(this,
this.getString(R.string.json_failed));
}
setTabs();
}
private void setTabs() {
addTab("Contacts", com.chr.tatu.sample.friendslist.ContactTab.class);
addTab("Month", com.chr.tatu.sample.friendslist.MonthTab.class);
addTab("Week", com.chr.tatu.sample.friendslist.WeekTab.class);
}
private void setupTabHost() {
mTabHost = (TabHost) findViewById(android.R.id.tabhost);
mTabHost.setup();
}
private void setupTab(final View view, final String tag, Intent intent,
int id) {
View tabview = createTabView(mTabHost.getContext(), tag, id);
TabSpec setContent = mTabHost.newTabSpec(tag).setIndicator(tabview)
.setContent(intent);
mTabHost.addTab(setContent);
}
private void addTab(String labelId, Class<?> c) {
TabHost tabHost = getTabHost();
Intent intent = new Intent(this, c);
intent.putExtra("FRIENDS", response);
TabHost.TabSpec spec = tabHost.newTabSpec("tab" + labelId);
View tabIndicator = LayoutInflater.from(this).inflate(
R.layout.tab_indicator, getTabWidget(), false);
TextView title = (TextView) tabIndicator.findViewById(R.id.title);
title.setText(labelId);
spec.setIndicator(tabIndicator);
spec.setContent(intent);
tabHost.addTab(spec);
}
private static View createTabView(final Context context, final String text,
final int id)
{
View view = LayoutInflater.from(context).inflate(
R.layout.tab_indicator, null);
return view;
}
#Override
protected void onResume() {
if (bcr == null) {
bcr = new BcReceiver();
registerReceiver(bcr, new IntentFilter(MyUtils.BIRTHDAY_ALERT));
}
if (bcra == null) {
bcra = new BcReceiverAlarm();
registerReceiver(bcra, new IntentFilter(MyUtils.ALARM_RESET));
}
super.onResume();
}
public void loadContents() {
if (fb.getFriendsCount() > 0) {
return;
}
fb.setMyFriends(db.getAllFriends());
if (fb.getFriendsCount() > 0) {
notifyTabSample(Note.FRIENDLIST_CHANGED);
} else {
fb.reLoadAllFriends();
}
// 4. initiate alarm
if (!isAlarmSet) {
setAlarm(true);
}
}
private void setAlarm(boolean isON) {
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
if (isON) {
am.setRepeating(AlarmManager.RTC_WAKEUP, MyUtils
.getAlarmStartTimeAsLong(MyUtils.getAlarmHour(), MyUtils
.getAlarmMinute()), 24 * 60 * 60 * 1000,
mAlarmSender);
isAlarmSet = true;
Log.v(TAG, "TabSample- alarm set");
} else {
am.cancel(mAlarmSender);
isAlarmSet = true;
Log.v(TAG, "TabSample- alarm cancelled");
}
}
public void notifyTabSample(Note what) {
switch (what) {
case FRIENDLIST_RELOADED:
db.syncFriends(fb.getMyFriends());
sendBroadcast(new Intent(MyUtils.FRIENDLIST_CHANGED));
break;
case FRIENDLIST_CHANGED:
sendBroadcast(new Intent(MyUtils.FRIENDLIST_CHANGED));
// setup timer
break;
default:
break;
}
}
ContactTab.Java :-
public class ContactTab extends ListActivity {
private MyFacebook fb = MyFacebook.getInstance();
private BcReceiver bcr = null;
private MyAdapter adapter;
private List<MyFriend> list;
private ProgressDialog busyDialog;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
busyDialog = new ProgressDialog(this);
busyDialog.setIndeterminate(true);
busyDialog.setMessage("Refreshing");
}
private void refreshList() {
new Thread() {
public void run() {
list = fb.getAllFriends();
Log.v(TAG, "contactstab- refresh called. " + list.size());
adapter = new MyAdapter(ContactTab.this, list);
handler.sendEmptyMessage(0);
}
}.start();
}
#Override
protected void onResume() {
if (bcr == null) {
bcr = new BcReceiver();
registerReceiver(bcr, new IntentFilter(MyUtils.FRIENDLIST_CHANGED));
}
refreshList();
super.onResume();
}
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
MyFriend friend = (MyFriend) this.getListAdapter().getItem(position);
Intent intent = new Intent(ContactTab.this, PersonalGreeting.class);
intent.putExtra("fbID", friend.getFbID());
intent.putExtra("name", friend.getName());
intent.putExtra("pic", friend.getPic());
startActivity(intent);
}
public boolean onCreateOptionsMenu(Menu menu) {
new MenuInflater(getApplication()).inflate(R.layout.menu, menu);
return (super.onPrepareOptionsMenu(menu));
}
public boolean onOptionsItemSelected(MenuItem item) {
Intent intent;
switch (item.getItemId()) {
case R.id.globalGreeting:
intent = new Intent(ContactTab.this, com.chr.tatu.sample.friendslist.GlobalGreeting.class);
startActivity(intent);
break;
case R.id.Settings:
intent = new Intent(ContactTab.this, com.chr.tatu.sample.friendslist.Settings.class);
startActivity(intent);
}
return (super.onOptionsItemSelected(item));
}
public class BcReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
runOnUiThread(new Runnable() {
public void run() {
refreshList();
}
});
}
}
private Handler handler = new Handler() {
#Override
public void handleMessage(Message msg) {
setListAdapter(adapter);
//busyDialog.dismiss();
}
};
}
MonthTab.Java :-
public class MonthTab extends ListActivity {
private MyFacebook fb = MyFacebook.getInstance();
private BcReceiver bcr = null;
private MyAdapter adapter;
private List<MyFriend> list;
private ProgressDialog busyDialog;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
busyDialog = new ProgressDialog(this);
busyDialog.setIndeterminate(true);
busyDialog.setMessage("Please wait ...");
busyDialog.show();
refreshList();
}
private void refreshList() {
// list = fb.getFilteredFriends(Filter.MONTH);
list = fb.getFilteredFriends(Filter.MONTH);
adapter = new MyAdapter(MonthTab.this, list);
setListAdapter(adapter);
busyDialog.dismiss();
}
#Override
protected void onResume() {
if (bcr == null) {
bcr = new BcReceiver();
registerReceiver(bcr, new IntentFilter(MyUtils.FRIENDLIST_CHANGED));
}
super.onResume();
}
#Override
#SuppressWarnings("unchecked")
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
MyFriend friend = (MyFriend) this.getListAdapter().getItem(position);
Intent intent = new Intent(MonthTab.this, PersonalGreeting.class);
intent.putExtra("fbID", friend.getFbID());
intent.putExtra("name", friend.getName());
startActivity(intent);
}
public boolean onCreateOptionsMenu(Menu menu) {
new MenuInflater(getApplication()).inflate(R.layout.menu, menu);
return (super.onPrepareOptionsMenu(menu));
}
public boolean onOptionsItemSelected(MenuItem item) {
Intent intent;
switch (item.getItemId()) {
case R.id.globalGreeting:
intent = new Intent(MonthTab.this, GlobalGreeting.class);
startActivity(intent);
break;
case R.id.Settings:
intent = new Intent(MonthTab.this, Settings.class);
startActivity(intent);
}
return (super.onOptionsItemSelected(item));
}
public class BcReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
runOnUiThread(new Runnable() {
public void run() {
refreshList();
}
});
}
}
}