Develop Reference

What is the easiest way to update a textView from a service?

I am making an app which consists of an activity and a service. By pressing a button the service is started, it collects data in the background from a sensor and classifies it and outputs a string. I want to display the string in a textView. Right now I can see in the log that the variable is updated 2 times every second, but when I try and update the textView from the service class nothing is happening unless I press the button, whenever I press the button, the string is displayed in the textView.
What is the easiest solution here? I tried to make the textView static and it still can't update it. Can you make it so that the view is updated automatically every second? Can I add a listener somehow? Since I am not very experienced I would like an easy solution that does not have to be a "good" one.
Here is my code
Activity:
public class CollectorActivity extends Activity {
private enum State {
IDLE, COLLECTING, TRAINING, CLASSIFYING
};
private final String[] mLabels = { Globals.CLASS_LABEL_STANDING,
Globals.CLASS_LABEL_WALKING, Globals.CLASS_LABEL_RUNNING,
Globals.CLASS_LABEL_OTHER };
private RadioGroup radioGroup;
private final RadioButton[] radioBtns = new RadioButton[4];
private Intent mServiceIntent;
private File mFeatureFile;
public static TextView mCurrentLabel;
private State mState;
private Button btnDelete;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
radioGroup = (RadioGroup) findViewById(R.id.radioGroupLabels);
radioBtns[0] = (RadioButton) findViewById(R.id.radioStanding);
radioBtns[1] = (RadioButton) findViewById(R.id.radioWalking);
radioBtns[2] = (RadioButton) findViewById(R.id.radioRunning);
radioBtns[3] = (RadioButton) findViewById(R.id.radioOther);
btnDelete = (Button) findViewById(R.id.btnDeleteData);
mCurrentLabel = (TextView) findViewById(R.id.textView);
mState = State.IDLE;
mFeatureFile = new File(getExternalFilesDir(null),
Globals.FEATURE_FILE_NAME);
mServiceIntent = new Intent(this, SensorsService.class);
}
public void onCollectClicked(View view) {
if (mState == State.IDLE) {
mState = State.COLLECTING;
((Button) view).setText(R.string.ui_collector_button_stop_title);
btnDelete.setEnabled(false);
radioBtns[0].setEnabled(false);
radioBtns[1].setEnabled(false);
radioBtns[2].setEnabled(false);
radioBtns[3].setEnabled(false);
int acvitivtyId = radioGroup.indexOfChild(findViewById(radioGroup
.getCheckedRadioButtonId()));
String label = mLabels[acvitivtyId];
Bundle extras = new Bundle();
extras.putString(Globals.CLASS_LABEL_KEY, label);
mServiceIntent.putExtras(extras);
startService(mServiceIntent);
} else if (mState == State.COLLECTING) {
mState = State.IDLE;
((Button) view).setText(R.string.ui_collector_button_start_title);
btnDelete.setEnabled(true);
radioBtns[0].setEnabled(true);
radioBtns[1].setEnabled(true);
radioBtns[2].setEnabled(true);
radioBtns[3].setEnabled(true);
stopService(mServiceIntent);
((NotificationManager) getSystemService(NOTIFICATION_SERVICE)).cancelAll();
}
}
public void onDeleteDataClicked(View view) {
if (Environment.MEDIA_MOUNTED.equals(Environment
.getExternalStorageState())) {
if (mFeatureFile.exists()) {
mFeatureFile.delete();
}
Toast.makeText(getApplicationContext(),
R.string.ui_collector_toast_file_deleted,
Toast.LENGTH_SHORT).show();
}
}
#Override
public void onBackPressed() {
if (mState == State.TRAINING) {
return;
} else if (mState == State.COLLECTING || mState == State.CLASSIFYING) {
stopService(mServiceIntent);
((NotificationManager) getSystemService(NOTIFICATION_SERVICE))
.cancel(Globals.NOTIFICATION_ID);
}
super.onBackPressed();
}
#Override
public void onDestroy() {
// Stop the service and the notification.
// Need to check whether the mSensorService is null or not.
if (mState == State.TRAINING) {
return;
} else if (mState == State.COLLECTING || mState == State.CLASSIFYING) {
stopService(mServiceIntent);
((NotificationManager) getSystemService(NOTIFICATION_SERVICE))
.cancelAll();
}
finish();
super.onDestroy();
}
And this is the "doInBackground" method in my service class. The line "CollectorActivity.mCurrentLabel.setText(classification);" is the problem. I want this to update the textView continously.
public class OnSensorChangedTask extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... arg0) {
Instance inst = new DenseInstance(mFeatLen);
inst.setDataset(mDataset);
Instance inst2 = new DenseInstance(65);
int blockSize = 0;
FFT fft = new FFT(Globals.ACCELEROMETER_BLOCK_CAPACITY);
double[] accBlock = new double[Globals.ACCELEROMETER_BLOCK_CAPACITY];
double[] re = accBlock;
double[] im = new double[Globals.ACCELEROMETER_BLOCK_CAPACITY];
double max = Double.MIN_VALUE;
while (true) {
try {
// need to check if the AsyncTask is cancelled or not in the while loop
if (isCancelled () == true)
{
return null;
}
// Dumping buffer
accBlock[blockSize++] = mAccBuffer.take().doubleValue();
if (blockSize == Globals.ACCELEROMETER_BLOCK_CAPACITY) {
blockSize = 0;
testList = new ArrayList<Double>();
// time = System.currentTimeMillis();
max = .0;
for (double val : accBlock) {
if (max < val) {
max = val;
}
}
fft.fft(re, im);
for (int i = 0; i < re.length; i++) {
double mag = Math.sqrt(re[i] * re[i] + im[i]
* im[i]);
inst.setValue(i, mag);
testList.add(i,mag);
im[i] = .0; // Clear the field
}
// Append max after frequency component
inst.setValue(Globals.ACCELEROMETER_BLOCK_CAPACITY, max);
inst2.setValue(Globals.ACCELEROMETER_BLOCK_CAPACITY, max);
testList.add(max);
classificationIndex = WekaClassifier.classify(testList.toArray());
classification = testLabel.get((int) classificationIndex);
CollectorActivity.mCurrentLabel.setText(classification);
inst.setValue(mClassAttribute, mLabel);
mDataset.add(inst);
Log.i("new instance", mDataset.size() + "");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}

In doInBackground(Void... arg0) change CollectorActivity.mCurrentLabel.setText(classification); to publishProgress(classification); then change second argument from Void to String: public class OnSensorChangedTask extends AsyncTask<Void, Srting, Void> and add onProgressUpdate().
Finally your code should looks like:
public class OnSensorChangedTask extends AsyncTask<Void, Srting, Void> {
#Override
protected Void doInBackground(Void... arg0) {
//...
publishProgress(classification);
//...
}
#Override
protected Void onProgressUpdate(String... classification) {
CollectorActivity.mCurrentLabel.setText(classification[0]);
}

How do I make a CountDown show/start at the same moment my Button gets enabled?

"How do I make a CountDown show at the same moment my Button gets enabled ?"
Additional info regarding the button: the Buttons Job is it to click 5 times through a stringarray displayed in a Textview to then get disabled for 5 seconds to do the same task again.
so ..I would like a CountDown to visually show those 5 seconds(the time the button is enabled) count down for the User to see.
sadly I dont have an idea how to connect my Button with an CountDown to let it know its supposed to count down at that particular time the Button is enabled.
Also I would like for the CountDown to start everytime the Button gets enabled.
I looked into https://developer.android.com/reference/android/os/CountDownTimer
but it doesnt seem to have a solution for that particular case.
thats my Code for the Button as of now :
next_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (currentnumber == list.length) {
currentnumber = 0;
}
if (Curclicks == mod - 1) {
next_button.setEnabled(false);
display.setText(list[currentnumber]);
currentnumber++;
handler.postDelayed(new Runnable() {
#Override
public void run() {
//the button will unlock after the delay specified
next_button.setEnabled(true);
Curclicks = 0;
}
}, delay);
} else {
display.setText(list[currentnumber]);
currentnumber++;
}
Curclicks++;
}
});
UI Thread code can solve that ? :
private void runThread() {
new Thread() {
public void run() {
while (delay == 5000) { //delay = 5000 ( 5 secs)
try {
runOnUiThread(new Runnable() {
#Override
public void run() {
timer.setText("" + delay);//timer=TxtView
}
});
Thread.sleep(300);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}.start();

Here is an example of how you can use the postDelayed() method of the Handler to create a count down. I have purposefully left the code a bit verbose so you can go through it step-by-step in order to see what is happening.
Create a few class variables and constants.
private static final long COUNT_DOWN_TICKS = 100l;
private static final long COUNT_DOWN_FINISH = 5000l;
private long countdownElapsed = 0l;
private Handler mCountDownHandler = new Handler();
COUNT_DOWN_FINISH is set to 5000 --> 5 sec. But can be changed to anything you need. Also I use COUNT_DOWN_TICKS set to 100 --> 0.1 sec, just in case you want to display a more precise count down.
From your OnClick() method just call startCountDown() to get the count down started.
private void startCountDown() {
try {
countdownElapsed = 0l;
next_button.setEnabled(false);
displayCountDown();
mCountDownHandler.postDelayed(mCountDownRunnable, COUNT_DOWN_TICKS);
}
catch (Exception ex){
Log.e(TAG, ex.getMessage());
}
}
private Runnable mCountDownRunnable = new Runnable() {
#Override
public void run() {
countdownElapsed = countdownElapsed + COUNT_DOWN_TICKS;
if(countdownElapsed >= COUNT_DOWN_FINISH){
releaseCountDownHandler();
next_button.setEnabled(true);
}
else{
mCountDownHandler.postDelayed(mCountDownRunnable, COUNT_DOWN_TICKS);
}
long secFull = countdownElapsed % 1000;
if(secFull == 0){
runOnUiThread(new Runnable() {
#Override
public void run() {
displayCountDown();
}
});
}
}
};
private void releaseCountDownHandler() {
try {
if(mCountDownRunnable != null) {
mCountDownHandler.removeCallbacks(mCountDownRunnable);
}
}
catch (Exception ex){
Log.e(TAG, ex.getMessage());
}
}
private void displayCountDown(){
long t = (COUNT_DOWN_FINISH - countdownElapsed)/1000;
String myTime = String.valueOf(t);
timer.setText(myTime);
}
In order to dispose of the Runnable properly you will want to call releaseCountDownHandler() from the onPause() method. This is just a short running Thread, but it should still not be ignored.
I prefer the Handler with the postDelay() method to the Thread.sleep() method--something about putting any thread to sleep is disconcerting. Also note that it is a good idea to get accustom to checking the elapsed time condition with ">=" RATHER than "==" depending on the implementation (e.g. you use SystemClock.elapsedRealtime() instead) the condition just might miss the exact value!
EDIT
Somewhere under the definition of your Activity class (for this example I will call it MainActivity) you will need to declare a few variables. Since they are being defined inside the class and NOT inside a method the are referred to as "class variables" and they have a scope of entire class when defined "private".
public class MainActivity extends AppCompatActivity {
//class variables
private static final long COUNT_DOWN_TICKS = 100l;
private static final long COUNT_DOWN_FINISH = 5000l;
private long countdownElapsed = 0l;
private Handler mCountDownHandler = new Handler();
private Button next_button;
private TextView timer;
....
}
You probably have declared the onClick() method inside the onCreate() method of the MainActivity class. So just add the following code:
next_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startCountDown();
}
Everything else I provide are method inside the MainActivity class...NOT inside any other method. So below the onCreate() method add all methods that I previously posted.
It will look something like this:
public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getSimpleName();
//class variables
private static final long COUNT_DOWN_TICKS = 100l;
private static final long COUNT_DOWN_FINISH = 5000l;
private long countdownElapsed = 0l;
private Handler mCountDownHandler = new Handler();
private Button next_button;
private TextView timer;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// you must compensate for the actual layout for your activity
setContentView(R.layout.activity_main);
// you must compensate for the actual id of the TextView
timer = findViewById(R.id.tvTimer);
// you must compensate for the actual id of the Button
next_button = findViewById(R.id.btnNext);
next_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startCountDown();
}
});
}
private void startCountDown() {
try {
countdownElapsed = 0l;
next_button.setEnabled(false);
displayCountDown();
mCountDownHandler.postDelayed(mCountDownRunnable, COUNT_DOWN_TICKS);
}
catch (Exception ex){
Log.e(TAG, ex.getMessage());
}
}
private Runnable mCountDownRunnable = new Runnable() {
#Override
public void run() {
countdownElapsed = countdownElapsed + COUNT_DOWN_TICKS;
if(countdownElapsed >= COUNT_DOWN_FINISH){
releaseCountDownHandler();
next_button.setEnabled(true);
}
else{
mCountDownHandler.postDelayed(mCountDownRunnable, COUNT_DOWN_TICKS);
}
long secFull = countdownElapsed % 1000;
if(secFull == 0){
runOnUiThread(new Runnable() {
#Override
public void run() {
displayCountDown();
}
});
}
}
};
private void releaseCountDownHandler() {
try {
if(mCountDownRunnable != null) {
mCountDownHandler.removeCallbacks(mCountDownRunnable);
}
}
catch (Exception ex){
Log.e(TAG, ex.getMessage());
}
}
private void displayCountDown(){
long t = (COUNT_DOWN_FINISH - countdownElapsed)/1000;
String myTime = String.valueOf(t);
timer.setText(myTime);
}
}

This function should do what you want, just call it into OnClickListener
public void countDown(Button yourBtn) {
new Thread() {
public void run() {
try {
int second = 10;
for (int i = second; i >= 1; i--) {
int finalI = i;
yourBtn.post(new Runnable() {
#Override
public void run() {
yourBtn.setText(String.valueOf(finalI))
}
});
Thread.sleep(1000); // Change text every 1s
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}.start();
}

This code is like my code above except this code introduces a "click counter". I have introduced a new class variable to keep track of how many times the button is clicked. I have also introduced a new constant called "NUMBER_OF_BUTTON_CLICKS" which servers as the upper limit of clicks.
The user can now click on the button (in this case) 5 times. On the fifth click the condition to trigger the startCountDown method is met and the button is disabled for 5 seconds.
public class MainActivity extends AppCompatActivity {
//Constant values
private static final String TAG = MainActivity.class.getSimpleName();
private static final int NUMBER_OF_BUTTON_CLICKS = 5;
private static final long COUNT_DOWN_TICKS = 100l;
private static final long COUNT_DOWN_FINISH = 5000l;
//class variables
private int howManyClicks = 0;
private long countdownElapsed = 0l;
private Handler mCountDownHandler = new Handler();
private Button next_button;
private TextView timer;
private TextView clicks;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// you must compensate for the actual layout for your activity
setContentView(R.layout.activity_main);
// you must compensate for the actual id of the TextView
timer = findViewById(R.id.tvTimer);
// Use this only if you want to display the number of clicks
// you might need to add this TextView if you want to display the number of clicks
clicks = findViewById(R.id.tvClicks);
// you must compensate for the actual id of the Button
next_button = findViewById(R.id.btnNext);
next_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
howManyClicks++;
if(howManyClicks >= NUMBER_OF_BUTTON_CLICKS){
startCountDown();
}
//Add this only if you want to see how many clicks were made
String myClicks = String.valueOf(howManyClicks);
clicks.setText(myClicks)
}
});
}
private void startCountDown() {
try {
countdownElapsed = 0l;
next_button.setEnabled(false);
displayCountDown();
mCountDownHandler.postDelayed(mCountDownRunnable, COUNT_DOWN_TICKS);
}
catch (Exception ex){
Log.e(TAG, ex.getMessage());
}
}
private Runnable mCountDownRunnable = new Runnable() {
#Override
public void run() {
countdownElapsed = countdownElapsed + COUNT_DOWN_TICKS;
if(countdownElapsed >= COUNT_DOWN_FINISH){
releaseCountDownHandler();
next_button.setEnabled(true);
// reset the clicks counter
howManyClicks = 0;
}
else{
mCountDownHandler.postDelayed(mCountDownRunnable, COUNT_DOWN_TICKS);
}
long secFull = countdownElapsed % 1000;
if(secFull == 0){
runOnUiThread(new Runnable() {
#Override
public void run() {
displayCountDown();
}
});
}
}
};
private void releaseCountDownHandler() {
try {
if(mCountDownRunnable != null) {
mCountDownHandler.removeCallbacks(mCountDownRunnable);
}
}
catch (Exception ex){
Log.e(TAG, ex.getMessage());
}
}
private void displayCountDown(){
long t = (COUNT_DOWN_FINISH - countdownElapsed)/1000;
String myTime = String.valueOf(t);
timer.setText(myTime);
//Add this only if you want to see how many clicks were made
String myClicks = String.valueOf(howManyClicks);
clicks.setText(myClicks)
}
}

Two-Dimensional Array with JSON data - Data is downloaded, but I can't access it (?)

So, I am creating a little trivia game for learning purposes, but I ran into a problem.
First, I had a specific Android Fragment obtaining the data from JSON, and I will simply use that data on the callback method and display it on TextViews and Buttons. Everything was working fine, however, every time I returned to that fragment, the same questions would be there. So I decided to handle that in a better way outside of the callback method.
The problem here is that apparently my Arrays are either null or their lengths is zero. Which is weird, because according to my LOG, data is being passed to those arrays on the callback method.
Here's my full fragment code. Thanks!
public class GameFragment extends Fragment {
private TextView txtQuestion;
private Button btnAnswer1;
private Button btnAnswer2;
private Button btnAnswer3;
private Button btnAnswer4;
private Questions[] gameQuestions;
private Questions[] animeQuestions;
private Questions[] techQuestions;
private Questions[] movieQuestions;
private Questions[][] gameCategories = new Questions[4][];
int correctAnswer = -1;
private TransparentProgressDialog progressBar;
private Handler handler;
private Runnable runnable;
Callback cb = new Callback<MyApiData>(){
#Override
public void success(MyApiData myApiData, Response response) {
gameCategories[0] = new Questions[myApiData.getCategory()[0].getQuestions(0).length];
gameCategories[1] = new Questions[myApiData.getCategory()[1].getQuestions(1).length];
gameCategories[2] = new Questions[myApiData.getCategory()[2].getQuestions(2).length];
gameCategories[3] = new Questions[myApiData.getCategory()[3].getQuestions(3).length];
//gameCategories = new Questions[][] {gameQuestions, animeQuestions, techQuestions, movieQuestions};
for(int i = 0; i < 4 ; i++){
for(int j = 0; j < gameCategories[i].length ; j++){
gameCategories[i][j] = myApiData.getCategory()[i].getQuestions(i)[j];
//Log.d("GameFragment", "gameCategories[i][j] - gameCategories["+i+"]["+j+"]: " + gameCategories[i][j].getQuestion());
}
}
//displayQuestion();
progressBar.dismiss();
displayQuestion();
}
#Override
public void failure(RetrofitError error) {
Log.d("GameScreen", "Callback failed!");
}
};
public GameFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_game, container, false);
txtQuestion = (TextView) view.findViewById(R.id.txtQuestion);
btnAnswer1 = (Button) view.findViewById(R.id.btnAnswer1);
btnAnswer2 = (Button) view.findViewById(R.id.btnAnswer2);
btnAnswer3 = (Button) view.findViewById(R.id.btnAnswer3);
btnAnswer4 = (Button) view.findViewById(R.id.btnAnswer4);
btnAnswer1.setOnClickListener(new View.OnClickListener() {
#Override public void onClick(View view) { checkAnswer(view); } });
btnAnswer2.setOnClickListener(new View.OnClickListener() {
#Override public void onClick(View view) { checkAnswer(view); } });
btnAnswer3.setOnClickListener(new View.OnClickListener() {
#Override public void onClick(View view) { checkAnswer(view); } });
btnAnswer4.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
checkAnswer(view);
}
});
handler = new Handler();
progressBar = new TransparentProgressDialog(getActivity(), R.drawable.loading_spinner);
runnable = new Runnable() {
#Override
public void run() {
if (progressBar.isShowing()) {
progressBar.dismiss();
}
}
};
//launchRingDialog();
//RestClient.get().getQuestions(cb);
// Inflate the layout for this fragment
return view;
}
public void launchRingDialog() {
new Thread(new Runnable() {
public void run(){
try {
Log.d("Thred", "Try");
progressBar.show();
RestClient.get().getQuestions(cb);
//Thread.sleep(10000);
} catch (Exception e) {
}
//progressBar.dismiss();
}
}).start();
}
public void checkAnswer(View v){
switch(v.getId()){
case R.id.btnAnswer1:
if(correctAnswer == 1){
feedback(true, btnAnswer1);
}else {
feedback(false, btnAnswer1);
}
break;
case R.id.btnAnswer2:
if(correctAnswer == 2){
feedback(true, btnAnswer2);
}else {
feedback(false, btnAnswer2);
}
break;
case R.id.btnAnswer3:
if(correctAnswer == 3){
feedback(true, btnAnswer3);
}else {
feedback(false, btnAnswer3);
}
break;
case R.id.btnAnswer4:
if(correctAnswer == 4){
feedback(true, btnAnswer4);
}else {
feedback(false, btnAnswer4);
}
break;
default: txtQuestion.setText("Error");
break;
}
}
public void feedback(Boolean correct, Button btn){
if(correct){
btn.setBackgroundColor(Color.GREEN);
btn.setText("CORRECT!");
}else{
btn.setBackgroundColor(Color.RED);
btn.setText("WRONG!");
}
}
#Override
public void onResume() {
super.onResume();
//displayQuestion();
}
public void displayQuestion(){
Random randomizer = new Random();
int randomQuestion;
int category = GTMain.choosenCategory;
if(category == 5){
category = randomizer.nextInt(4);
}
randomQuestion = randomizer.nextInt(25);
Log.d("displayQuestion", "Before if statements");
if(gameCategories != null && gameCategories.length != 0) {
Log.d("displayQuestion", "First if");
if(gameCategories[category] != null && gameCategories[category].length != 0){
Log.d("displayQuestion", "Second if");
txtQuestion.setText(gameCategories[category][randomQuestion].getQuestion());
correctAnswer = gameCategories[category][randomQuestion].getCorrectAnswer();
Log.d("displayQuestion()", "correctAnswer: " + correctAnswer);
btnAnswer1.setText(gameCategories[category][randomQuestion].getAnswers().getA1());
btnAnswer2.setText(gameCategories[category][randomQuestion].getAnswers().getA2());
btnAnswer3.setText(gameCategories[category][randomQuestion].getAnswers().getA3());
btnAnswer4.setText(gameCategories[category][randomQuestion].getAnswers().getA4());
}
}
}
}
PS: On my main activity, I check to see which fragment should be loaded. If it's the fragment that contains the components to display the questions and answer (the one from the code above), I call the following method: gameFragment.launchRingDialog(); (and yes, I have created an instance of my GameFragment fragment before calling that method!)

When onResume() is called, your RestClient.get().getQuestions(cb) is still running in background, and your call displayQuestion(), so of course nothing is shown.
Can you put displayQuestion() inside success() of your callback?
Callback cb = new Callback<MyApiData>(){
#Override
public void success(MyApiData myApiData, Response response) {
....
for(int i = 0; i < 4 ; i++){
for(int j = 0; j < gameCategories[i].length ; j++){
...
}
}
displayQuestion();
}
....
};
I would also suggest you to remove displayQuestion() in onResume() method.

How to properly use a Handler

I'm trying to create a tuner app right now and it has two errors, both stemming from Handlers.
public class Pitch extends Fragment {
private static final String TAG = "Pitch";
private TextView tv_pitch;
private TextView tv_note;
View rootView;
Context mContext;
Tuner tn;
private Handler mHandler;
private final static double[] stringFreqs = {82.41, 110.0, 146.83, 196.00, 246.94, 329.63};
private static HashMap<Double, String> stringNames = new HashMap<>();
Tuner.PitchDetectedListener listener = new Tuner.PitchDetectedListener() {
#Override
public void onPitchDetected(double pitch, double amplitude) {
Log.d(TAG, "Pitch: " + pitch + " Amplitude: " + amplitude);
if (amplitude > 1000000.0) {
double doublePitch = pitch * 2;
double halfPitch = pitch / 2;
for (double freq : stringFreqs) {
if (pitch > freq - 3 && pitch < freq + 3) {
Log.d(TAG, stringNames.get(freq) + " with pitch of " + pitch);
display_color(pitch, freq);
return;
}
}
for (double freq : stringFreqs) {
if (doublePitch > freq - 3 && doublePitch < freq + 3) {
Log.d(TAG, stringNames.get(freq) + " with pitch of " + pitch);
display_color(doublePitch, freq);
return;
}
}
for (double freq : stringFreqs) {
if (halfPitch > freq - 3 && halfPitch < freq + 3) {
Log.d(TAG, stringNames.get(freq) + " with pitch of " + pitch);
display_color(halfPitch, freq);
return;
}
}
}
}
};
private void display_color(final double pitch, final double freq) {
mHandler.post(new Runnable() {
#Override
public void run() {
tv_note.setText(stringNames.get(freq));
tv_pitch.setText(Double.toString(pitch));
}
});
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.activity_tuner, container, false);
final BoxInsetLayout tuner = (BoxInsetLayout) rootView.findViewById(R.id.tuner_box);
final ImageView start = (ImageView) rootView.findViewById(R.id.tuner);
final ImageView stop = (ImageView) rootView.findViewById(R.id.tuner);
mContext = getActivity().getApplicationContext();
Typeface font = Typeface.createFromAsset(mContext.getAssets(), "fonts/Foglihten-068.otf");
tv_note.setTypeface(font);
tv_note.setText("-");
mHandler = new Handler(getMainLooper());
tv_note = (TextView) rootView.findViewById(R.id.tv_note);
int i = 0;
stringNames.put(stringFreqs[i++], "E");
stringNames.put(stringFreqs[i++], "A");
stringNames.put(stringFreqs[i++], "D");
stringNames.put(stringFreqs[i++], "G");
stringNames.put(stringFreqs[i++], "B");
stringNames.put(stringFreqs[i], "e");
start.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
tn.run();
}
});
stop.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
tn.stop();
}
});
tv_pitch = (TextView) tuner.findViewById(R.id.tv_pitch);
tv_note = (TextView) tuner.findViewById(R.id.tv_note);
return rootView;
tn = new Tuner(listener);
}
public void onPause() {
tn.stop();
super.onPause();
}
}
My errors are in these lines:
mHandler.post(new Runnable() {
mHandler = new Handler(getMainLooper());
The first line results in cannot resolve method 'post(java.lang.Runnable)', and the second line results in cannot resolve method 'getMainLooper.'
Can anyone help figure out what's going wrong?

Check your imports. You accidentally imported java.util.logging.Handler instead of android.os.Handler.
Most of the time you create object where you need a handler on UI thread so you're safe to use this:
private final Handler mHandler = new Handler();
A more general approach will look like this (post to UI thread from other threads):
private final Handler mHandler = new Handler(Looper.getMainLooper());

CountDownTimer trivia game score - Android (java)

I have a trivia game that displays 10 questions and they each have a 10 second timer. I have 2 problems that do not function correctly.
Firstly, If the timer runs out on a question, it displays the next question but the timer does not reset. The textviews stay at "Time's up!" and "Time Elapsed: 10000" instead of restarting the timer on the new question that is displayed.
Lastly, on the Results page the correct score is not displayed in the textview. The percentage textview displays correctly but the score textview displays "android.widget.TextView#416473c" or some other random memory location.
The program never crashes just functions incorrectly. Any code structure or other suggestions is much appreciated! This is my first android mobile app attempt and I am slowly and strugglingly through it. Yet enjoying it! :)
QuesteionView.java
public class QuestionView extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.questionviewmain);
answer1 = (Button)findViewById(R.id.answer1);
answer2 = (Button)findViewById(R.id.answer2);
answer3 = (Button)findViewById(R.id.answer3);
answer4 = (Button)findViewById(R.id.answer4);
question = (TextView)findViewById(R.id.question);
queries = getIntent().getParcelableArrayListExtra("queries");
timer = (TextView)findViewById(R.id.timer);
timeElapsedView = (TextView)findViewById(R.id.timeElapsedView);
cdTimer = new Timer(startTime, interval);
loadQuestion();
}
public void loadQuestion() {
if(i == 9) {
endQuiz();
} else {
if(!timerHasStarted) {
cdTimer.start();
timerHasStarted = true;
} else {
cdTimer.cancel();
timerHasStarted = false;
}
answer = queries.get(i).getCorrectAnswer();
question.setText(queries.get(i).getQuery());
answer1.setText(queries.get(i).getA1());
answer2.setText(queries.get(i).getA2());
answer3.setText(queries.get(i).getA3());
answer4.setText(queries.get(i).getA4());
answer1.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
queries.get(i).setSelectedAnswer(0);
if(answer == 0) {
correctAnswers++;
nextQuestion();
} else {
wrongAnswers++;
nextQuestion();
}
}
});
//same type of code for buttons for answers 2 through 4.
}
}
public void nextQuestion() {
score = score + timeElapsed;
i++;
loadQuestion();
}
public class Timer extends CountDownTimer {
public Timer(long startTime, long interval) {
super(startTime, interval);
}
public void onFinish() {
if(i == 9) {
cdTimer.cancel();
} else {
timer.setText("Time's up!");
timeElapsedView.setText("Time Elapsed: " + String.valueOf(startTime));
wrongAnswers++;
nextQuestion();
}
}
public void onTick(long millisUntilFinished) {
timer.setText("Time remain: " + Long.toString(millisUntilFinished));
timeElapsed = startTime - millisUntilFinished;
timeElapsedView.setText("Time Elapsed: " + Long.toString(timeElapsed));
}
}
public void endQuiz() {
Intent intent = new Intent(QuestionView.this, Results.class);
intent.putExtra("correctAnswers", correctAnswers);
intent.putExtra("wrongAnswers", wrongAnswers);
intent.putExtra("score", score);
intent.putParcelableArrayListExtra("queries", queries);
startActivity(intent);
}
}
Results.java
public class Results extends Activity {
QuestionView qv = new QuestionView();
ArrayList<Question> queryList = qv.getQueries();
int cAnswers;
int wAnswers;
long score;
ArrayList<Question> qs;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.resultsmain);
cAnswers = getIntent().getIntExtra("correctAnswers", -1);
wAnswers = getIntent().getIntExtra("wrongAnswers", -1);
score = getIntent().getLongExtra("score", -1);
qs = getIntent().getParcelableArrayListExtra("queries");
Button mainmenuBtn = (Button)findViewById(R.id.mainmenuBtn);
mainmenuBtn.setText("Main Menu");
mainmenuBtn.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
restart();
}
});
showResults();
}
public void showResults() {
ArrayList<TextView> tList = new ArrayList<TextView>(9);
TextView header = (TextView)findViewById(R.id.header);
header.setText("SUMMARY");
TextView percentage = (TextView)findViewById(R.id.percentage);
percentage.setText(Integer.toString(10 * cAnswers) + "%");
TextView score = (TextView)findViewById(R.id.score);
String s = "" + score;
score.setText(s);
TextView q1 = (TextView)findViewById(R.id.q1);
TextView q2 = (TextView)findViewById(R.id.q2);
TextView q3 = (TextView)findViewById(R.id.q3);
TextView q4 = (TextView)findViewById(R.id.q4);
TextView q5 = (TextView)findViewById(R.id.q5);
TextView q6 = (TextView)findViewById(R.id.q6);
TextView q7 = (TextView)findViewById(R.id.q7);
TextView q8 = (TextView)findViewById(R.id.q8);
TextView q9 = (TextView)findViewById(R.id.q9);
TextView q10 = (TextView)findViewById(R.id.q10);
tList.add(q1);
tList.add(q2);
tList.add(q3);
tList.add(q4);
tList.add(q5);
tList.add(q6);
tList.add(q7);
tList.add(q8);
tList.add(q9);
tList.add(q10);
for(int i = 0; i < tList.size(); i++) {
tList.get(i).setText(qs.get(i).getQuery());
if(qs.get(i).getSelectedAnswer() == qs.get(i).getCorrectAnswer()) {
tList.get(i).setTextColor(Color.GREEN);
} else {
tList.get(i).setTextColor(Color.RED);
}
}
}
public void restart() {
Intent intent = new Intent(Results.this, MainMenu.class);
startActivity(intent);
}
}

From all of that code, this is what I think is happening
Firstly, If the timer runs out on a question, it displays the next question but the timer does not reset. The textviews stay at "Time's up!" and "Time Elapsed: 10000" instead of restarting the timer on the new question that is displayed.
This appears to be due to you not setting your timerHasStarted variable to false after the time runs out so I would set that to false probably when you load your next question or after you show the results.
Lastly, on the Results page the correct score is not displayed in the textview. The percentage textview displays correctly but the score textview displays "android.widget.TextView#416473c" or some other random memory location.
This is because you are setting your q variables to the textview and getting the id. You need something like q1.getText().toString()
You have multiple variables with the same name score. So change it to
TextView score2 = (TextView)findViewById(R.id.score);
String s = "" + score;
score2.setText(s);

the score displays not what you expected because you assigned the String s = "" + score where score is what you named for the Textview which obviously not an integer and not equivalent to the score that the user has. :)