Database Develop

Please help with Java homework!!!

Okay here's the thing:
I have an assignment in Java class that's due in 1.5 hours and figured that this would be the best place to ask since you guys are (hopefully) good at this kind of stuff.
Here's the code:
/**
* Exercise 3.
*
* Complete the setBalances method below to set all accounts in an array to the specified value.
*
* The test methods should pass.
*
*/
public class AccountMethods {
public static void main(String[] args) {
Account[] accounts = {new Account(100, "joe"),
new Account(200, "jane"),
new Account(300, "jerry")};
testSetBalances(accounts, 50);
testBalanceNonNegative();
}
public static void setBalances(Account[] accounts, double value) {
double balance = 0;
for (int i = 0; i < accounts.length; i++) {
balance += accounts.getBalance();
}
}
public static boolean testSetBalances(Account[] accounts, double value) {
setBalances(accounts, value);
for (int i = 0; i < accounts.length; i++) {
if (accounts.getBalance() != value) {
System.out.println("testSetBalances fails on element " + i);
return false;
}
}
System.out.println("testSetBalances passes.");
return true;
}
public static boolean testBalanceNonNegative() {
Account a = new Account(100, "jim");
a.setBalance(-100);
if (a.getBalance() < 0) {
System.out.println("testBalanceNonNegtaive fails");
return false;
} else {
System.out.println("testBalanceNonNegative passes.");
return true;
}
}
}
The bold part is what I'm suppose to be working with, but I can't get it to pass in the testSetBalances method. I don't know if I'm explaining this right, but when I'm compiling the code, it's suppose to say:
testSetBalances passes
But instead, it's saying: testSetBalances fails on element 0
Don't worry about the other parts of the code because the assignment for that is done already.

[Q] How to update a textView every second.

I have a textview that shows your amount of money and i would like the ui to update every second to visually show how much money you have in real time. Would i be able to accomplish this with a timer?, and if so what would it look like.

Hello,
You should do inside your class, outside of any method:
Code:
TextView tv;
String calculatedString;
MyAsyncTask mAsync = null;
Timer timer = null;
TimerTask task = null;
private class MyAsyncTask extends AsyncTask<String, Void, String> {
public MyAsyncTask(){
}
@Override
protected String doInBackground(String... params) {
//Background operation in a separate thread
//Write here your code to run in the background thread
//calculate here whatever you like
calculatedString = ....;
return null;
}
@Override
protected void onPostExecute(String result) {
//Called on Main UI Thread. Executed after the Background operation, allows you to have access to the UI
tv.setText(calculatedString);
}
@Override
protected void onPreExecute() {
//Called on Main UI Thread. Executed before the Background operation, allows you to have access to the UI
}
}
inside the onCreate after super and setContentView:
Code:
tv = (TextView) findViewById(R.id.tv); //your tv id here
final Handler handler = new Handler();
timer = new Timer();
task = new TimerTask() {
@Override
public void run() {
handler.post(new Runnable() {
public void run() {
MyAsyncTask mAsync = new MyAsyncTask();
mAsync.execute();
}
});
}
};
timer.schedule(task, 0, 1000); //Every 1 second
If you still need help, feel free to ask

I have attached 2 screenshots showing the errors i was given after inputting. Any idea how to fix this?
mmdeveloper10 said:
Hello,
You should do inside your class, outside of any method:
Code:
TextView tv;
String calculatedString;
MyAsyncTask mAsync = null;
Timer timer = null;
TimerTask task = null;
private class MyAsyncTask extends AsyncTask<String, Void, String> {
public MyAsyncTask(){
}
@Override
protected String doInBackground(String... params) {
//Background operation in a separate thread
//Write here your code to run in the background thread
//calculate here whatever you like
calculatedString = ....;
return null;
}
@Override
protected void onPostExecute(String result) {
//Called on Main UI Thread. Executed after the Background operation, allows you to have access to the UI
tv.setText(calculatedString);
}
@Override
protected void onPreExecute() {
//Called on Main UI Thread. Executed before the Background operation, allows you to have access to the UI
}
}
inside the onCreate after super and setContentView:
Code:
tv = (TextView) findViewById(R.id.tv); //your tv id here
final Handler handler = new Handler();
timer = new Timer();
task = new TimerTask() {
@Override
public void run() {
handler.post(new Runnable() {
public void run() {
MyAsyncTask mAsync = new MyAsyncTask();
mAsync.execute();
}
});
}
};
timer.schedule(task, 0, 1000); //Every 1 second
If you still need help, feel free to ask
Click to expand...
Click to collapse

Hello,
For the first image:
You have to import the AsyncTask.
add this
Code:
import android.os.AsyncTask;
with the other imports in your java file.
For your second image:
You haven't wrote the line
Code:
setContentView(R.layout.activity_main);
under your super.onCreate(savedInstanceState); and then the code I said above (I said that on my post )
inside onCreate, where activity_main is your xml layout. And you should have inside that layout, a TextView with an id "tv" (or whatever you like)
and then:
Code:
tv = (TextView) findViewById(R.id.tv); //your tv id here
R.id.tv must much the id you have in your layout. Replace it with the actual id of your TextView. If your id is "tv", write R.id.tv, if it is "mytv" write R.id.mytv. ( I said that on my post also)
Can you show your layout file? (XML - your activity_main.xml). You said that you have a TextView Where is your TextView?

Ok I fixed the problems stated and now only have these two errors remaining
mmdeveloper10 said:
Hello,
For the first image:
You have to import the AsyncTask.
add this
Code:
import android.os.AsyncTask;
with the other imports in your java file.
For your second image:
You haven't wrote the line
Code:
setContentView(R.layout.activity_main);
under your super.onCreate(savedInstanceState); and then the code I said above (I said that on my post )
inside onCreate, where activity_main is your xml layout. And you should have inside that layout, a TextView with an id "tv" (or whatever you like)
and then:
Code:
tv = (TextView) findViewById(R.id.tv); //your tv id here
R.id.tv must much the id you have in your layout. Replace it with the actual id of your TextView. If your id is "tv", write R.id.tv, if it is "mytv" write R.id.mytv. ( I said that on my post also)
Can you show your layout file? (XML - your activity_main.xml). You said that you have a TextView Where is your TextView?
Click to expand...
Click to collapse

Have you imported this?
Code:
import java.util.logging.Handler;
If so, change it to
Code:
import android.os.Handler;

Im not at the computer but I think that should solve my issue I will keep you updated
Sent from my HTC6525LVW using XDA Free mobile app

Hey thanks so much its working perfectly now :good:

TabHost display content above

Hi. Is there a way for a tabhost to display content of it's tabs above insted below like in all examples i found on net?

just use buttons and framelayout as fragment container
change fragment inside container when user click button

Thank you. And just another question, can I somehow display name of tab which is opened in action bar so I don't need to create new LinearLayout bellow it?

NVM. Found it: setTitle()

Is it possible to use Views (Button) from one fragment in another?

I need to have button in my other fragment. When I press on it so it returns to some other or opens new fragment. But I can't make OnClickListener for button that will be initialized later and it isn't on my Main_Layout. How can I solve this so I can use that button to move between my tabs or open new frames?
Code:
onCreate(){
home.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
setFragment(new HomeFragment());
setTitle("Home");
}
});
signin.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
setFragment(new SigninFragment());
setTitle("Sign In");
}
});
}
protected void setFragment(Fragment fragment) {
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction =
fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.frameLayout, fragment);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
public class HomeFragment extends Fragment {
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState)
{
return inflater.inflate(R.layout.home_fragment,container,false);
}
}

My app crashes on start. Anyone see the problem?
Code:
public class Fragment3 extends Fragment implements View.OnClickListener {
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState)
{
View myView = inflater.inflate(R.layout.fragment3_layout, container, false);
final Button b12=(Button) myView.findViewById(R.id.button35);
b12.setOnClickListener(this);
return myView;
}
[user=439709]@override[/user]
public void onClick(View v) {
}
}

Trouble with implementing In App Billing into my app...

So I was programming in some In app Billing code for my Android app using Android Studio. I was following an Android tutorial called 'Preparing your In-app Billing Application' at the Android Developer website (not allowed to give a link because I'm a new user). All was going well, until I get to the part where I have to paste their code into my code. Check out their code put into mine (I left the base64EncodedPublicKey empty so nobody would steal it):
Code:
public class MainActivity extends ActionBarActivity {
//Add other java files to the main class
private JokeBook mJokeBook = new JokeBook();
private ColorWheel mColorWheel = new ColorWheel();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Declare View variables
final TextView jokeLabel = (TextView) findViewById(R.id.jokeTextView);
final Button showJokeButton = (Button) findViewById(R.id.showJokeButton);
final RelativeLayout relativeLayout = (RelativeLayout) findViewById(R.id.relativeLayout);
final Button moreJokes = (Button) findViewById(R.id.moreJokes);
//On Click
View.OnClickListener listener = new View.OnClickListener() {
@Override
public void onClick(View v) {
String joke = mJokeBook.getJoke();
//Update label with fact
jokeLabel.setText(joke);
int color = mColorWheel.getColor();
relativeLayout.setBackgroundColor(color);
showJokeButton.setTextColor(color);
moreJokes.setTextColor(color);
}
};
showJokeButton.setOnClickListener(listener);
goToTwitter();
goToFacebook();
goToExxellerate();
IabHelper mHelper;
@Override
public void [U]onCreate(Bundle savedInstanceState)[/U] {
// ...
String base64EncodedPublicKey = "";
// compute your public key and store it in base64EncodedPublicKey
[B]mHelper = new IabHelper(this, base64EncodedPublicKey);[/B]
}
mHelper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
public void onIabSetupFinished(IabResult result) {
if (!result.isSuccess()) {
// Oh noes, there was a problem.
[I]Log.d(TAG, "Problem setting up In-app Billing: " + result);[/I]
}
// Hooray, IAB is fully set up!
}
});
@Override
public void [U]onDestroy()[/U] {
super.onDestroy();
if (mHelper != null) mHelper.dispose();
mHelper = null;
}
}
The code that they gave me had many errors when pasted into Android Studio, which were:
TAG has private access in 'android.support.v4.app.FragmentActivity' (Italicized text)
Annotations are not allowed here (@Override)
; expected (Underlined text)
IabHelper (android.view.View.onClickListener, String) in IabHelper cannot be applied to (com.exxellerate.joketeller.MainActivity, String) (Bolded Text)
Any help with fixing there errors? I'm a beginner at code and very confused that the code they gave me was wrong...

Using Intent(send mail) in Navigation drawer

I want to send mail from Navigation Drawer using the intent. First, my MainActivity.
Code:
else if(id==R.id.nav_mail) {
fragment = new MailFragment();
}
and MailFragment.
Code:
public class MailFragment extends Fragment {
public MailFragment() {
Intent email = new Intent(Intent.ACTION_SEND);
email.setType("plain/text");
String[] address = {"********@gmail.com"};
email.putExtra(Intent.EXTRA_EMAIL, address);
email.putExtra(Intent.EXTRA_SUBJECT, "Subject___****");
email.putExtra(Intent.EXTRA_TEXT, "Text___****.\n\n");
startActivity(email);
}
// @Override
// public View onCreateView(LayoutInflater inflater, ViewGroup container,
// Bundle savedInstanceState) {
// TextView textView = new TextView(getActivity());
// textView.setText(R.string.hello_blank_fragment);
// return textView;
// }
}
Run to create crash. The reason why I used to use fragment is because I made the simple screen change function fragment.
If you need more code, comment plz.

I didn't get what you are trying to do. If you are trying to invoke the "Select your mail app" screen and then send a message thru the Intent all of this when the user clicks on a row on the drawer then you should just copy the code to
Code:
else if(id==R.id.nav_mail) {
// here
}
without switching any fragment.
By the way, as far as I know, the fragment's public constructor must be empty.

You cannot do it from Fragment's constructor. Move your code to onActivityCreated() method.

qlife1146 said:
I want to send mail from Navigation Drawer using the intent. First, my MainActivity.
Code:
else if(id==R.id.nav_mail) {
fragment = new MailFragment();
}
and MailFragment.
Code:
public class MailFragment extends Fragment {
public MailFragment() {
Intent email = new Intent(Intent.ACTION_SEND);
email.setType("plain/text");
String[] address = {"********@gmail.com"};
email.putExtra(Intent.EXTRA_EMAIL, address);
email.putExtra(Intent.EXTRA_SUBJECT, "Subject___****");
email.putExtra(Intent.EXTRA_TEXT, "Text___****.\n\n");
startActivity(email);
}
// @Override
// public View onCreateView(LayoutInflater inflater, ViewGroup container,
// Bundle savedInstanceState) {
// TextView textView = new TextView(getActivity());
// textView.setText(R.string.hello_blank_fragment);
// return textView;
// }
}
Run to create crash. The reason why I used to use fragment is because I made the simple screen change function fragment.
If you need more code, comment plz.
Click to expand...
Click to collapse
Creating a new Intent in the constructor is a really bad idea. An example from the android's developer guide
Code:
public class MainActivity extends AppCompatActivity {
public static final String EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
/** Called when the user taps the Send button */
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.editText);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}
}