I want to make a callback function in the ShipInfoManager to inform the MainActivity to do some action.
If I put onEvent() into Runnable, it runs.
However If I put it like this, it shows an error.
Is there any way to fire the callback after loading data?
Or, is there any way to do the callback like Android's API's LocatioManger's requestLocationUpdates, giving a callback when the data/variables is changed?
Thank you for any replies!
MyCallback Interface:
interface MyCallback {
void callbackCall();
}
ShipInfoManager class:
public class ShipInfoManager {
Context mContext;
public ShipInfoManager(Context _mContext) {
this.mContext = _mContext;
reloadData();
startTimer();
}
MyCallback callback;
void onEvent() {
callback.callbackCall();
}
private void startTimer() {
/* RUN EVERY MIN */
final Handler handler = new Handler();
Timer timer = new Timer();
TimerTask doAsynchronousTask = new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
#SuppressWarnings("unchecked")
public void run() {
try {
reloadData();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
};
// TEMP SUSPEND FROM PREVENTING RELOAD //
timer.schedule(doAsynchronousTask, 0, 5000);
}
/* JSON handling and extraction */
private void reloadData() {
//Do sth to reload the data
//After reload, I want to fire the callback
onEvent();
}
}
It looks like you haven't any listeners to your callback and you're not checking for this.
You should replace your ShipInfoManager with this:
public class ShipInfoManager {
public interface MyCallback {
void callbackCall();
}
public void setCustomEventListener(MyCallback eventListener) {
callback = eventListener;
}
Context mContext;
public ShipInfoManager(Context _mContext) {
this.mContext = _mContext;
reloadData();
startTimer();
}
MyCallback callback;
void onEvent() {
// Check if we have listeners
if (callback != null)
callback.callbackCall();
}
private void startTimer() {
/* RUN EVERY MIN */
final Handler handler = new Handler();
Timer timer = new Timer();
TimerTask doAsynchronousTask = new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
#SuppressWarnings("unchecked")
public void run() {
try {
reloadData();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
};
// TEMP SUSPEND FROM PREVENTING RELOAD //
timer.schedule(doAsynchronousTask, 0, 5000);
}
/* JSON handling and extraction */
private void reloadData() {
//Do sth to reload the data
//After reload, I want to fire the callback
onEvent();
}
}
Inside your Activity or Fragment you should have something like:
public class MainActivity extends ActionBarActivity implements ShipInfoManager.MyCallback {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ShipInfoManager s = new ShipInfoManager(this);
s.setCustomEventListener(this);
}
#Override
public void callbackCall() {
}
}
I changed my MainActivity like this. It works now.
Thank you for your suggestion and reply!!!!!
public class MainActivity extends ActionBarActivity {
ShipInfoManager mShipInfo;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mShipInfo = new ShipInfoManager(this);
Log.i("Show Ship List Size", String.valueOf(mShipInfo.get_shipsList().size()));
Log.i("Show Ship - 6", String.valueOf(mShipInfo.getShip(6).getShip_name()));
mShipInfo.callback = new ShipInfoManager.MyCallback() {
#Override
public void callbackCall() {
Log.i("Call Back", "it is called");
}
};
}
Related
I am running a recursive handler which runs some code. I am posting the handler using a HandlerThread. I want to run the next recursive call only after the completion of the previous call.
Is it possible to do so? If not what are the alternatives.
HandlerThread ht = new HandlerThread();
ht.start();
Handler h = new Handler(ht.getLooper());
h.post(new Runnable() {
#override
public void run(){
//Some code
h.postDelay(this,1000);
}
});
Your code should work, but if you want a complete example how to run something recursively using HandlerThread, here it is:
public class Main2Activity extends AppCompatActivity {
private MyWorkerThread mWorkerThread;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
mWorkerThread = new MyWorkerThread("myWorkerThread");
final Runnable task = new Runnable() {
#Override
public void run() {
Log.d("TAG", "Done.");
mWorkerThread.postTask(this);
}
};
mWorkerThread.start();
mWorkerThread.prepareHandler();
mWorkerThread.postTask(task);
}
#Override
protected void onDestroy() {
mWorkerThread.quit();
super.onDestroy();
}
}
class MyWorkerThread extends HandlerThread {
private Handler mWorkerHandler;
public MyWorkerThread(String name) {
super(name);
}
public void postTask(Runnable task){
mWorkerHandler.postDelayed(task, 1000); // set timeout which needed
}
public void prepareHandler(){
mWorkerHandler = new Handler(getLooper());
}
}
Don't forget to call handlerThread.quit() in onDestroy
What I want to do is call a method which is placed in my MainActivity.java file from another subclass. But everytime i want to call this method, my app crashes.
I already tried to make SetGerateStat() static but that didn't change anything. Also, I can build the apk without any errors, the application only crashes when the SetGerateStat() is called from the Thread.
What am I doing wrong here?
My code is below (please note that this is only a snippet):
MainActivity.java:
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
private CheckedTextView gerätestat;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void setGeraeteStat(boolean x) {
if (x==true) {
gerätestat.setCheckMarkDrawable(android.R.drawable.presence_online);
} else {
gerätestat.setCheckMarkDrawable(android.R.drawable.presence_busy);
}
}
public void onClick(View v) {
if(v==button_refresh) {
Thread connection = new Thread(new Conn("refresh", MainActivity.this));
connection.start();
}
}
Conn.java:
public class Conn implements Runnable {
private MainActivity act;
private String actioncommand;
public Conn(String a) {
actioncommand = a;
act = null;
}
public Conn(String a, MainActivity m) {
actioncommand = a;
act = m;
}
public void run() {
switch(actioncommand) {
case "refresh": {
act.setGeraeteStat(true);
}
break;
}
}
Have you forgot to initialize gerätestat ? You have to initialize gerätestat after setcontentview. After that use runOnUIThread method as below
public void setGeraeteStat(final boolean x){
runOnUiThread (new Runnable() {
public void run() {
if (x==true) {
gerätestat.setCheckMarkDrawable(android.R.drawable.presence_online);
} else {
gerätestat.setCheckMarkDrawable(android.R.drawable.presence_busy);
}
}
});}
I need to execute some tasks when my application is closed.
I have made a service for do this and tried many things, but i don't have the good result.
If someone have a tutorial or some path to follow, it would be great
This is my service:
public class TrackersImporter extends Service {
private static TrackersImporter instance;
private static long refreshDelay = 1; // Minutes
private Looper mServiceLooper;
private ServiceHandler mServiceHandler;
private boolean isInit = false;
public ArrayList<Tracker> trackers = new ArrayList<>();
public static TrackersImporter getInstance(){
if (instance == null)
instance = new TrackersImporter();
return instance;
}
#Override
public void onCreate() {
HandlerThread thread = new HandlerThread("TrackersImporter",
Process.THREAD_PRIORITY_BACKGROUND);
thread.start();
mServiceLooper = thread.getLooper();
mServiceHandler = new ServiceHandler(mServiceLooper);
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
try {
Toast.makeText(this, "onStartCommand", Toast.LENGTH_SHORT).show();
Message message = mServiceHandler.obtainMessage();
message.arg1 = startId;
mServiceHandler.sendMessage(message);
} catch (Exception e) {
Log.w("TrackersImporter", e.getMessage());
}
return START_STICKY;
}
public void addTracker(Tracker tracker) {
trackers.add(tracker);
}
protected void showToast(final String msg){
Handler handler = new Handler(Looper.getMainLooper());
handler.post(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_SHORT).show();
}
});
}
// Object responsible for
private final class ServiceHandler extends Handler {
public ServiceHandler(Looper looper) {
super(looper);
}
#Override
public void handleMessage(Message msg) {
addTracker(Runkeeper.getInstance(MainActivity.getActivity()));
addTracker(Strava.getInstance(MainActivity.getActivity()));
startImport(MainActivity.getActivity().getBaseContext(), MainActivity.getActivity().getAppUser(), trackers);
stopSelf(msg.arg1);
}
/**
* Perform data imports.
* Imports are performed only 1 time.
* Additional calls to this method are equivalent to no-op.
* Call init() then performImport() for each TrackerImportable
* #param user user receiving the datas
*/
public void startImport(Context context, User user, ArrayList<Tracker> trackers) {
Context ctx = MainActivity.getActivity().getApplicationContext();
LocalDateTime now = new LocalDateTime();
if (Preferences.getPref(ctx, "tracker_import_date") == "")
Preferences.setPref(ctx, "tracker_import_date", now.toString());
LocalDateTime past = LocalDateTime.parse(Preferences.getPref(ctx, "tracker_import_date"));
long duration = new Duration(past.toDateTime(), now.toDateTime()).getStandardMinutes();
if (isInit)
return;
if (duration > refreshDelay) {
Preferences.setPref(ctx, "tracker_import_date", now.toString());
for (Tracker tracker : trackers) {
if (tracker.isEnabled() && Tracker.isUserEnabled(context, tracker.getName())) {
tracker.init();
tracker.performImport(user);
}
}
}
isInit = true;
}
}
}
This is my mainActivity
public class MainActivity extends BaseActivity {
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
if (ConnectivityUtil.isConnected(this.getApplicationContext())) {
initGoogleFit();
initTrackers(appUser);
}
}
private void initTrackers(User user) {
Intent trackersIntentService = new Intent(this, TrackersImporter.class);
trackersIntentService.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
this.startService(trackersIntentService);
}
#Override
protected void onResume() {
...
if (ConnectivityUtil.isConnected(this.getApplicationContext())) {
initTrackers(appUser);
}
}
}
First Create one launcher Activity which is like your Main Activity.
In Activity "onCreate" Method you need to start Service and Do Some thing if you wont in Service "onStartCommand" Method.
public class MainActivity extends Activity {
ArrayList<Integer> list;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startService(new Intent(MainActivity.this,TrackersImporter.class);
}
public class TrackersImporter extends Service {
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
// do something
Log.v(TAG ,"Service is started");
}
}
And also Register this Service at manifest.xml like this.
<service android:name=".TrackersImporter"></service>
if you like stop service
stopService(new Intent(MainActivity.this,TrackersImporter.class);
I have an activity in which I call Service on background, I am quite new to AIDL
my codes are as follows:
on Activity
//declaration
private Intent mIntentInvenueService;
private IInvenueService mIInvenueService;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mIntentInvenueService = new Intent(this, InvenueService.class);
startService(mIntentInvenueService);
}
private final ServiceConnection mServiceConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
mIInvenueService = IInvenueService.Stub.asInterface(service);
try {
mIInvenueService.registerCallback(mCallback);
} catch (RemoteException e) {
e.printStackTrace();
}
}
#Override
public void onServiceDisconnected(ComponentName name) {
mIInvenueService = null;
try {
mIInvenueService.unregisterCallback(mCallback);
} catch (RemoteException e) {
e.printStackTrace();
}
}
};
private final IInvenueServiceCallback.Stub mCallback = new IInvenueServiceCallback.Stub() {
#Override
public void onReceiveResponse() throws RemoteException {
runOnUiThread(new Runnable() {
public void run() {
if (flagChanged){
}
else
{
cAdapter.notifyDataSetChanged();
}
}
});
}
};
public void onResume() {
super.onResume();
bindService(mIntentInvenueService, mServiceConnection, BIND_AUTO_CREATE);
}
#Override
public void onDestroy() {
super.onDestroy();
unbindService(mServiceConnection);
unregisterReceiver(mBroadcastReceiver);
}
ON MY SERVICE:
private final RemoteCallbackList<IInvenueServiceCallback> mCallbacks = new RemoteCallbackList<IInvenueServiceCallback>();
private boolean isUpdated = false;
#Override
public IBinder onBind(Intent intent) {
return mBinder;
}
private final IInvenueService.Stub mBinder = new IInvenueService.Stub() {
#Override
public void startProcess() throws RemoteException {
Timer timer = new Timer();
timer.schedule(new TimerTask() {
public void run() {
Toast.makeText(......).show()// Toast Here
}
}, 60000, 60000);
}
#Override
public void unregisterCallback(IInvenueServiceCallback callback)
throws RemoteException {
mCallbacks.unregister(callback);
}
#Override
public void registerCallback(IInvenueServiceCallback callback)
throws RemoteException {
mCallbacks.register(callback);
}
};
My AIDL:
interface IInvenueService {
void startProcess();
void registerCallback(IInvenueServiceCallback callback);
void unregisterCallback(IInvenueServiceCallback callback);
}
My Question is why is that the Toast not showing? Am I missing something that start process isnt working?
Any Help?
You should show Toasts from the UIThread, using a TimerTask will cause it to run on a seperate thread.
Try posting a runnable with the Toast to a Handler.
I get this error "Can't create handler inside thread that has not called Looper.prepare()"
Can you tell me how to fix it?
public class PaymentActivity extends BaseActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.payment);
final Button buttonBank = (Button) findViewById(R.id.buttonBank);
buttonBank.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
progressDialog = ProgressDialog.show(PaymentActivity.this, "",
"Redirecting to payment gateway...", true, true);
new Thread() {
public void run() {
try {
startPayment("Bank");
} catch (Exception e) {
alertDialog.setMessage(e.getMessage());
handler.sendEmptyMessage(1);
progressDialog.cancel();
}
}
}.start();
}
});
StartPayment Method:
private void startPayment(String id) {
Bundle b = getIntent().getExtras();
final Sail sail = b.getParcelable(Constant.SAIL);
final Intent bankIntent = new Intent(this, BankActivity.class);
try {
Reservation reservation = RestService.createReservation(
sail.getId(),
getSharedPreferences(Constant.PREF_NAME_CONTACT, 0));
bankIntent.putExtra(Constant.RESERVATION, reservation);
// <workingWithDB> Storing Reservation info in Database
DBAdapter db = new DBAdapter(this);
db.open();
#SuppressWarnings("unused")
long rowid;
rowid = db.insertRow(sail.getId(), sail.getFrom(),
sail.getTo(), sail.getShip(), sail.getDateFrom().getTime(),
sail.getPrice().toString(), reservation.getId().floatValue());
db.close();
// </workingWithDB>
String html = PaymentService.getRedirectHTML(id, reservation);
bankIntent.putExtra(Constant.BANK, html);
} catch (Exception e) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
AlertDialog alertDialog = builder.create();
alertDialog.setMessage(e.getMessage());
alertDialog.show();
}
startActivity(bankIntent);
}
You should know that when you try to modify your UI , the only thread who can do that is the UiThread.
So if you want to modify your UI in another thread, try to use the method: Activity.runOnUiThread(new Runnable);
Your code should be like this :
new Thread() {
public void run() {
YourActivity.this.runOnUiThread(new Runnable(){
#Override
public void run(){
try {
startPayment("Bank");//Edit,integrate this on the runOnUiThread
} catch (Exception e) {
alertDialog.setMessage(e.getMessage());
handler.sendEmptyMessage(1);
progressDialog.cancel();
}
});
}
}
}.start();
I assume you create a Handler in startPayment() method. You can't do that, as handlers can be created on th UI thread only. Just create it in your activity class.
Instead of new Thread() line, try giving
this.runOnUiThread(new Runnable() {
you cant change any UI in thread you can use runOnUIThread or AsyncTask for more detail about this click here
I've found that most thread handling can be replaced by AsyncTasks like this:
public class TestStuff extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button buttonBank = (Button) findViewById(R.id.button);
buttonBank.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
new StartPaymentAsyncTask(TestStuff.this).execute((Void []) null);
}
});
}
private class StartPaymentAsyncTask extends AsyncTask<Void, Void, String> {
private ProgressDialog dialog;
private final Context context;
public StartPaymentAsyncTask(Context context) {
this.context = context;
}
#Override
protected void onPreExecute() {
dialog = new ProgressDialog(context);
// setup your dialog here
dialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
dialog.setMessage(context.getString(R.string.doing_db_work));
dialog.setCancelable(false);
dialog.show();
}
#Override
protected String doInBackground(Void... ignored) {
String returnMessage = null;
try {
startPayment("Bank");
} catch (Exception e) {
returnMessage = e.getMessage();
}
return returnMessage;
}
#Override
protected void onPostExecute(String message) {
dialog.dismiss();
if (message != null) {
// process the error (show alert etc)
Log.e("StartPaymentAsyncTask", String.format("I received an error: %s", message));
} else {
Log.i("StartPaymentAsyncTask", "No problems");
}
}
}
public void startPayment(String string) throws Exception {
SystemClock.sleep(2000); // pause for 2 seconds for dialog
Log.i("PaymentStuff", "I am pretending to do some work");
throw new Exception("Oh dear, database error");
}
}
I pass in the Application Context to the Async so it can create dialogs from it.
The advantage of doing it this way is you know exactly which methods are run in your UI and which are in a separate background thread. Your main UI thread isn't delayed, and the separation into small async tasks is quite nice.
The code assumes your startPayment() method does nothing with the UI, and if it does, move it into the onPostExecute of the AsyncTask so it's done in the UI thread.
Try
final Handler handlerTimer = new Handler(Looper.getMainLooper());
handlerTimer.postDelayed(new Runnable() {
public void run() {
......
}
}, time_interval});