[Solved] How to add backbutton functionality to app

What you looking is call BottomNavigationView. You should place the id in onNavigationItemSelected. MainActivty public class MainActivity extends AppCompatActivity { private TextView mTextMessage; private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener = new BottomNavigationView.OnNavigationItemSelectedListener() { @Override public boolean onNavigationItemSelected(@NonNull MenuItem item) { switch (item.getItemId()) { case R.id.navigation_home: mTextMessage.setText(R.string.title_home); return true; case R.id.back: finish(); return true; } return false; } }; … Read more

[Solved] Read last incomming SMS from phone inbox

You just need to register a BroadcastReceiver with IntentFilter of “android.provider.Telephony.SMS_RECEIVED”. Then you can get a received message from the intent like this: try { Object[] messages = (Object[]) intent.getSerializableExtra(“pdus”); for (Object msg : messages) { byte[] bytes = (byte[]) msg; SmsMessage message = SmsMessage.createFromPdu(bytes); String messageBody = message.getDisplayMessageBody(); // this is your SMS message … Read more

[Solved] Java Array Search, on a value which i’snt inside the array Exception Error

Yes. For example, if you were trying to ‘catch’ an InvalidYearException, you would do something like this: try { // Your code (the code that will possibly cause an exception to be thrown) } catch(InvalidYearException exception) { // Your code (the code that will be executed when you ‘catch’ an InvalidYearException) // for example: System.out.println(“Error!” … Read more

[Solved] printing an array with arbitrary nesting levels, in java [closed]

You can do this recursivly by checking if the current element is again a list and by using the toString-method which every object in java has. public void printList(List<Object> a) { for (Iterator<Object> it = a.iterator(); it.hasNext();) { Object item = it.next(); if (item instanceof List) printList((List<Object>) item); else System.out.print(item + “, “); } } … Read more

[Solved] Returning from a function once an async operation is done [duplicate]

Personally, RxJava is overkill. All you need is to pass in the continuation function as a parameter class Validator { void validate(DataListener dl){ DataProvider.getInstance(dl); } And now, wherever you call this method, put in your new DataListener. Don’t assign a result of validate() to a variable solved Returning from a function once an async operation … Read more

[Solved] Explain the output of the java program [duplicate]

So the quick answer, the output will be feline cougar c c The reason now. new Cougar() will create an instance Cougar, since a Cougar is a Feline, Feline‘s constructor is the first thing called in the Cougar‘s constructor. This explain “feline cougar”. public Cougar() { System.out.print(“cougar “); } is actually looking like public Cougar() … Read more

[Solved] I have a Java homework problem that I cannot seem to figure out. Using regular expression and/or API classes like Pattern, Matcher is not allowed [closed]

I have a Java homework problem that I cannot seem to figure out. Using regular expression and/or API classes like Pattern, Matcher is not allowed [closed] solved I have a Java homework problem that I cannot seem to figure out. Using regular expression and/or API classes like Pattern, Matcher is not allowed [closed]