I've googled already, and all topics say the same solution handler.removeCallbacks(null) or handler.removeCallbacksAndMessages(null). But none of them worked for me.
Handler handler;
Runnable runnable;
#Override
protected void onCreate(Bundle savedInstanceState) {
//...
handler = new Handler();
runnable = new Runnable() {
#Override
public void run() {
time -= 100;
if(time == 0){
Intent i = new Intent(Question.this, WrongAnswer.class);
startActivity(i);
finish();
}
else{
handler.postDelayed(this, 100);
}
}
};
handler.postDelayed(runnable,3000);
//...
}
And here is the case where the activity exits before the time runs out:
if(myAnswer == correctAnswer)
{
Intent i = new Intent(this, CorrectAnswer.class);
startActivity(i);
handler.removeCallbacksAndMessages(null);
finish();
}
You need to make your runnable global before handler.removeCallbacks(runnable) would work. Also, you can use a global variable for checking if you cancelled already (this is just for safety)
private boolean isCancelled = false;
private Runnable mRunnable = new Runnable() {
#Override
public void run() {
if (isCancelled) return;
time -= 100;
if(time == 0){
Intent i = new Intent(Question.this, WrongAnswer.class);
startActivity(i);
finish();
}
else{
handler.postDelayed(this, 100);
}
}
};
and then:
isCancelled = true;
handler.removeCallbacks(mRunnable);
Related
I'm a beginner in Android programming. I'm trying to display a timer for an upgrade in my game to show how long the upgrade will be activated for. In my collision flag I call Looper.prepare and start my thread class as the logcat suggested I do. How would I get this to run on one looper?
Here is the snippet that starts the thread.
BigGapUpgrade.java
public boolean playerCollectUpgrade(Player player){
if(Rect.intersects(rectangle, player.getRectangle())){
Looper.prepare();
bigGapUpgradeHandler.start();
}
return Rect.intersects(rectangle, player.getRectangle());
}
And here is my thread class
BigGapUpgradeHandler.java
public class BigGapUpgradeHandler extends Thread {
TimerTask scanTask;
Timer timer = new Timer();
#Override
public void run() {
Looper.prepare();
scanTask = new TimerTask() {
public void run() {
}
};
timer.schedule(scanTask, 0, 4000);
CountDownTimer countDownTimer = new CountDownTimer(4000, 100) {
#Override
public void onTick(long l) {
Log.i(TAG, "onTick: ");
}
#Override
public void onFinish() {
timer.cancel();
Log.i(TAG, "onFinish: ");
}
}.start();
Looper.loop();
}
}
After running it I get this error
W/System.err: java.lang.RuntimeException: Only one Looper may be created per thread
--Edit
Here is the solution I came up with.
-- Solution
new Handler(Looper.getMainLooper()).post(new Runnable() {
#Override
public void run() {
CountDownTimer countDownTimer = new CountDownTimer(5000,100) {
#Override
public void onTick(long millisUntilFinished) {
millis = millisUntilFinished/100;
}
#Override
public void onFinish() {
}
}.start();
}
});
OK, So what you can do is just use a TimerTask. That creates it's own background thread for you do stuff:
// This TimerTask Updates the UI so it needs a reference to the Activity.
static class PowerUpTimerTask extends TimerTask
{
WeakReference<AppCompatActivity> mActivity;
long mInterval;
long mPeriod;
public PowerUpTimerTask(AppCompatActivity activity, long period, long interval)
{
mActivity = new WeakReference<>(activity);
mInterval = interval;
mPeriod = period;
}
#Override
public void run()
{
AppCompatActivity activity = mActivity.get();
if (activity != null)
{
final TextView timerTextView = activity.findViewById(R.id.timerTextView);
mPeriod -= mInterval;
if (mPeriod > 0)
{
// Set time remaining
activity.runOnUiThread(new Runnable()
{
#Override
public void run()
{
timerTextView.setText(String.valueOf(mPeriod));
}
});
}
else
{
// Out of time...clear the Text and stop the timer task.
activity.runOnUiThread(new Runnable()
{
#Override
public void run()
{
timerTextView.setText("");
}
});
Log.d(TAG, "Timer done. Canceling.");
cancel();
}
}
else
{
// Cancel this timer task since we don't have a reference to
// the Activity any more.
Log.d(TAG, "Lost reference to Activity. Canceling.");
cancel();
}
}
}
Then you can start your Timer task like so:
...
// Will count down from 10 by 1s.
mPowerUpTimerTask = new PowerUpTimerTask(this, powerUpTime, 1);
// Schedule for every second.
Timer t = new Timer();
t.scheduleAtFixedRate(mPowerUpTimerTask, 1000, 1000);
...
Here is a link to this running sample:
https://github.com/didiergarcia/TimerTaskExample
I think you have to use LocalBroadcastManager for the timing to continuously in loop. Please check below code for for that :-
private void startTimer() {
countDownTimer = new CountDownTimer(Constant.getInstance().ANSWER_TIME_IN_SECOND * 1000, 1000) {
public void onTick(long millisUntilFinished) {
remaininTimeInMillies = millisUntilFinished;
tvTimer.setText(getTime(Integer.parseInt(String.valueOf(millisUntilFinished))));
}
public void onFinish() {
Intent intent = new Intent(Constant.getInstance().TIMER_RECEIVER);
LocalBroadcastManager.getInstance(PatientDetailActivity.this).sendBroadcast(intent);
}
};
countDownTimer.start();
}
private String getTime(int milliSec) {
int minut = 0, second = 0;
minut = milliSec / 60000;
second = (milliSec - (minut * 60000)) / 1000;
String strMinute = "", strSecond = "";
if (minut < 10) {
strMinute = "0" + String.valueOf(minut);
} else {
strMinute = String.valueOf(minut);
}
if (second < 10) {
strSecond = "0" + String.valueOf(second);
} else {
strSecond = String.valueOf(second);
}
return strMinute + ":" + strSecond;
}
#Override
protected void onResume() {
LocalBroadcastManager.getInstance(this).registerReceiver(timerBroadcast, new IntentFilter(Constant.getInstance().TIMER_RECEIVER));
super.onResume();
}
#Override
protected void onDestroy() {
LocalBroadcastManager.getInstance(this).unregisterReceiver(timerBroadcast);
super.onDestroy();
}
Thanks and Hope that will help you
I'm a student trying to create an app for my miniproject for one of my modules and I'm trying to create an app that grabs data from a server every few seconds so it's updated. I tried using java timer and timerTask to run the code repeatedly but the program only run once and the get-button doesn't work as intended (suppose to grab data instantly) after implementing the timer. Android Emulator
public class MainActivity extends AppCompatActivity implements OnClickListener{
private Button speed;
private TextView result;
Timer timer;
TimerTask timerTask;
private TextView sSpeed;
final StringBuilder builder = new StringBuilder();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
result = (TextView) findViewById(R.id.result);
sSpeed = (TextView) findViewById(R.id.sSpeed);
speed = (Button) findViewById(R.id.get_button);
speed.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View view) {
getWebsite();
}
});
View aboutButton = this.findViewById(R.id.about_button);
aboutButton.setOnClickListener(this);
View exitButton = this.findViewById(R.id.exit_button);
exitButton.setOnClickListener(this);
}
public void onClick(View v) {
switch (v.getId()){
case R.id.get_button:
getWebsite();
break;
case R.id.about_button:
Intent i = new Intent(this, About.class);
startActivity(i);
break;
case R.id.exit_button:
finish();
break;
}
}
private void getWebsite(){
new Thread(new Runnable() {
#Override
public void run() {
try{
Document doc = Jsoup.connect("http://10.0.2.2:8080/Start_Stop_buttons_UTF8.html").get();
// Elements element = doc.getElementsByTag("p");
Elements element = doc.select("p");
//String title = doc.title();
builder.append(title).append("\n");
for (Element tag : element){
builder.append("\n\n").append(tag.text());
}
}catch(IOException e){
//e.printStackTrace();
builder.append("Error : ").append(e.getMessage()).append("\n");
}
runOnUiThread(new Runnable() {
#Override
public void run() {
String a = builder.toString(); // parse data from html into new string
a = a.substring(a.indexOf(":")+1, a.indexOf("Control")).trim();//trim string content
String b = builder.toString();
b = b.substring(11,b.indexOf(":")+1).trim();
double speed = Double.parseDouble(a);//convert string into double
if (speed<1000)
Log.i("HTML text","too slow");
else if((speed> 1500))Log.i("HTML text","too fast!");
result.setText(a);
sSpeed.setText(b);
}
});
}
}).start();
}
protected void onResume() {
super.onResume();
startTimer();
}
public void startTimer(){
timer = new Timer();
timerTask = new TimerTask() {
#Override
public void run() {
getWebsite();
}
};
timer.schedule(timerTask,1500,3000);
}
public void stopTimer(){
if(timer != null){
timer.cancel();
timer.purge();
}
}
}
Am I implementing the timer correctly to run getwebsite() repeatedly and able to get an instant update when get-button is clicked like it should have? Or is there a better way to implement these features using different method?
You are never calling the startTimer method in your ClickListener. You make one call to getWebsite. Change your call to startTimer.
speed.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View view) {
startTimer();
}
});
You also might want to check if the timer is already running before you start a new one. To do that assign a null value on your stopTimer method e.g.
public void stopTimer(){
if(timer != null){
timer.cancel();
timer.purge();
timer = null;
}
}
And your startTimer would look like this
public void startTimer(){
if(timer != null) return; // don't start multiple timers
timer = new Timer();
timerTask = new TimerTask() {
#Override
public void run() {
getWebsite();
}
};
timer.schedule(timerTask,1500,3000);
}
I am having a problem with the Timer in my quiz Game. Essentially it's a multiple choice game and the player is timed on each question. I have the timer starting when the application starts and the player sees the first question. My issue is that if the player answers the question correctly or Incorrectly the timers starts giving random values, even though I reset the timer to 30 seconds on the onclick method. How do I get the timer to start at 30 seconds and countdown normally.
public class MainActivity extends AppCompatActivity {
//Views
TextView questionTextView;
TextView mscoreTextView;
TextView mtimerTextView;
Button mchoice1;
Button mchoice2;
Button mchoice3;
Button mchoice4;
//Constructors
private questions Question = new questions();
private Answers cAnswers = new Answers();
private choices Choices = new choices();
//Variables
private int questionNumber = 0;
private int mScore = 0;
private String correctAnswer;
public void onClick(View view) {
Button answer1 = (Button) view;
if(answer1.getText() == correctAnswer) {
mScore = mScore + 1;
Toast.makeText(getApplicationContext(), "CORRECT!!", Toast.LENGTH_SHORT).show();
mtimerTextView.setText("30s");
runTimer();
} else {
Toast.makeText(getApplicationContext(), "WRONG!!", Toast.LENGTH_SHORT).show();
mtimerTextView.setText("30s");
runTimer();
}
updateScore(mScore);
updateUI();
}
private void updateScore(int points) {
mscoreTextView.setText("" + points + "/" + Question.getLength());
}
public void runTimer() {
new CountDownTimer(30100, 1000) {
#Override
public void onTick(long millisUntilFinished) {
String tick = String.valueOf(millisUntilFinished/1000 + "s");
mtimerTextView.setText(tick);
}
#Override
public void onFinish() {
Toast.makeText(getApplicationContext(), "TIME RAN OUT!!", Toast.LENGTH_LONG).show();
mtimerTextView.setText("0s");
updateUI();
}
}.start();
}
private void updateUI () {
if (questionNumber < Question.getLength()) {
questionTextView.setText(Question.getQuestion(questionNumber));
mchoice1.setText(Choices.getChoices(questionNumber, 1));
mchoice2.setText(Choices.getChoices(questionNumber, 2));
mchoice3.setText(Choices.getChoices(questionNumber, 3));
mchoice4.setText(Choices.getChoices(questionNumber, 4));
correctAnswer = cAnswers.getAnswer(questionNumber);
questionNumber ++;
} else {
Toast.makeText(getApplicationContext(), "This is the last question", Toast.LENGTH_LONG).show();
//Intent intent = new Intent(MainActivity.this, HighScoreActivity.class);
//intent.putExtra("Score", mScore);
//startActivity(intent);
}
runTimer();
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
questionTextView = (TextView) findViewById(R.id.questionTextView);
mchoice1 = (Button) findViewById(R.id.choice1);
mchoice2 = (Button) findViewById(R.id.choice2);
mchoice3 = (Button) findViewById(R.id.choice3);
mchoice4 = (Button) findViewById(R.id.choice4);
mtimerTextView = (TextView) findViewById(R.id.timerTextView);
mscoreTextView = (TextView) findViewById(R.id.scoreTextView);
updateScore(mScore);
updateUI();
}
}
The thing is, you never really cancel a timer you've launched. Along with this, for every time you need a timer - you create a new one, which is not essential. The following must solve your problem:
You need to store CountDownTimer in a class field:
private CountDownTimer timer;
Then you can create it once on the start of app:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
timer = createTimer();
...
}
CreateTimer function:
public void createTimer() {
timer = new CountDownTimer(30100, 1000) {
#Override
public void onTick(long millisUntilFinished) {
...
}
#Override
public void onFinish() {
...
}
}
}
So when you need to run timer you just call:
timer.start();
And when user gives an answer, you need to cancel timer first, then start it again:
public void onClick(View view) {
...
timer.cancel();
timer.start();
...
}
Also: you have some duplicated code in your OnClick() method. Regardless of user's answer correctness you need to run timer and set a value to mtimerTextView, so basically you want to do it outside of if-else construction.
You have to define a variable inside a CountDownTimer class.
public void runTimer() {
new CountDownTimer(30100, 1000) {
private int time = 30;
#Override
public void onTick(long millisUntilFinished) {
mtimerTextView.setText(time--+"s");
}
#Override
public void onFinish() {
Toast.makeText(getApplicationContext(), "TIME RAN OUT!!", Toast.LENGTH_LONG).show();
mtimerTextView.setText("0s");
updateUI();
}
}.start();
}
Cancelable Timer
If you want your Timer cancelable you have to define it as a global variable.
private CountDownTimer timer; // global variable
start the timer by calling the below runTimer() method.
public void runTimer() {
timer = new CountDownTimer(30100, 1000) {
private int time = 30;
#Override
public void onTick(long millisUntilFinished) {
mtimerTextView.setText(time--+"s");
}
#Override
public void onFinish() {
Toast.makeText(getApplicationContext(), "TIME RAN OUT!!", Toast.LENGTH_LONG).show();
mtimerTextView.setText("0s");
updateUI();
}
}.start();
}
You can cancel the timer by calling the below method.
public void stopTimer(){
if(timer != null){
timer.cancel();
}
}
Hope this will help
I don't know how to explain better. I have this timer, and after it finish counting it should call another class (popup) and after that other function in the same class where the counter is.
public class MyCount extends CountDownTimer {
public MyCount(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
public void onFinish() {
Intent i = new Intent(getApplicationContext(), PogresanOdgovor.class);
i.putExtra("tacanOdgovor", tacanOdg);
startActivity(i);
mHandler.postDelayed(mLaunchTask,2200);
brojacPogresnihOdgovora++;
}
After first pass, my score is 2 instead of 1, then 6, the 14...This delayed method is simply the next question:
Runnable mLaunchTask = new Runnable() {
public void run() {
nextQuestion();
brojacVremena.start();
}
};
I call exactly the same method as the one in onFinish() when user answer wrong and it works fine.
MyCount brojacVremena = new MyCount(6000, 1000);
final OnClickListener clickListener = new OnClickListener() {
public void onClick(View v) {
Answer ans = (Answer) v.getTag();
if (ans.isCorrect) {
brojacVremena.cancel();
brojacTacnihOdgovora = brojacTacnihOdgovora + 5;
Intent i = new Intent("rs.androidaplikacijekvizopstekulture.TACANODGOVOR");
startActivity(i);
mHandler.postDelayed(mLaunchTask,1200);
}
else{
brojacVremena.cancel();
brojacPogresnihOdgovora++;
Intent i = new Intent(getApplicationContext(), PogresanOdgovor.class);
i.putExtra("tacanOdgovor", tacanOdg);
startActivity(i);
mHandler.postDelayed(mLaunchTask,2200);
}
};
I found my error. I called my counter twice. Here:
nextQuestion();
brojacVremena.start();
and below in the very same nextQuestion method:
public void nextQuestion() {
brojacVremena.start();
.
.
.
I don't know how that happened.
I cant figure out why i cant set text to my textView tv.
getting:
E/AndroidRuntime(686): android.view.ViewRoot$CalledFromWrongThreadException:
Only the original thread that created a view hierarchy can touch its views.
I tried many ways to make it right.
As you can see i tried Handler because i had the same problem with toasts. Now toast works but setText doesnt :((
Please someone help me, how should i configure this handler?
public class calculate extends Activity implements OnClickListener {
private myService myService; //bound service instance
private boolean serviceStarted;
View show_map;
View data;
View start;
View stop;
public TextView tv;
private Location loc;
private boolean initiated=false;
private float distance=0;
UIHandler uiHandler;
route_calc rc;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.calculate);
tv=(TextView)findViewById(R.id.textView1);
show_map=findViewById(R.id.button1);
show_map.setOnClickListener(this);
data=findViewById(R.id.button2);
data.setOnClickListener(this);
start=findViewById(R.id.button3);
start.setOnClickListener(this);
stop=findViewById(R.id.button4);
stop.setVisibility(View.INVISIBLE);
stop.setOnClickListener(this);
HandlerThread uiThread = new HandlerThread("UIHandler");
uiThread.start();
uiHandler = new UIHandler( uiThread.getLooper());
}
public void onDestroy(){
super.onDestroy();
}
#Override
public void onClick(View v) {
Intent i;
switch(v.getId()){
case R.id.button1:
i=new Intent(this,Map.class);
startActivity(i);
break;
case R.id.button2:
i=new Intent(this,data.class);
startActivity(i);
break;
case R.id.button3:
startService();
break;
case R.id.button4:
stopService();
break;
}
}
//connection between this activity and service myService
ServiceConnection myServConn = new ServiceConnection() {
#Override
public void onServiceDisconnected(ComponentName arg0) {
myService = null;
}
#Override
public void onServiceConnected(ComponentName arg0, IBinder binder) {
myService = ((myService.MyBinder)binder).getMyService();
}
};
private void startService() {
Intent intent = new Intent(this, myService.class);
startService(intent);
//Bind MyService here
bindService(intent, myServConn, BIND_AUTO_CREATE);
stop.setVisibility(View.VISIBLE);
serviceStarted = true;
rc = new route_calc();
rc.start();
}
private void stopService() {
if(serviceStarted) {
Intent intent = new Intent(this, myService.class);
//Unbind MyService here
unbindService(myServConn);
stopService(intent);
stop.setVisibility(View.INVISIBLE);
serviceStarted = false;
}
}
void showToast(String s){
handleUIRequest(s);
}
void setText(){
handleUISetText();
}
class route_calc extends Thread{
Location begin;
public void run() {
float temp;
while(!initiated){
try{
loc=myService.getLocation();
}
catch(Exception e){
}
if(loc!=null){
begin=loc;
initiated=true;
showToast("zadzialalo");
}
}
while(true){
loc=myService.getLocation();
temp=begin.distanceTo(loc);
distance=distance+temp;
tv.setText("przejechales "+distance+" m");
System.err.println(distance);
begin=loc;
try {
this.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
private final class UIHandler extends Handler
{
public static final int DISPLAY_UI_TOAST = 0;
public static final int TV_SET_TEXT = 1;
public UIHandler(Looper looper)
{
super(looper);
}
public void handleMessage(Message msg)
{
switch(msg.what)
{
case UIHandler.DISPLAY_UI_TOAST:
{
Context context = getApplicationContext();
Toast t = Toast.makeText(context, (String)msg.obj, Toast.LENGTH_LONG);
t.show();
}
case UIHandler.TV_SET_TEXT:
{
tv.setText("przejechałeś "+distance+" m");
}
default:
break;
}
}
}
protected void handleUIRequest(String message)
{
Message msg = uiHandler.obtainMessage(UIHandler.DISPLAY_UI_TOAST);
msg.obj = message;
uiHandler.sendMessage(msg);
}
protected void handleUISetText(){
Message msg=uiHandler.obtainMessage(UIHandler.TV_SET_TEXT);
uiHandler.sendMessage(msg);
}
}
It seems like you put your entire Activity here, and that it also includes a service, and you didn't try to narrow down your problem.
in your route_calc thread you call showToast, this is probably one of your problems, you should call showToast (or any other UI function) from your Handler.
Something like this:
Do anything you want on your thread:
new Thread(new Runnable()
{
#Override
public void run()
{
try
{
someHeavyStuffHere(); //Big calculations or file download here.
handler.sendEmptyMessage(SUCCESS);
}
catch (Exception e)
{
handler.sendEmptyMessage(FAILURE);
}
}
}).start();
When your data is ready, tell the handler to put it in a view and show it:
protected Handler handler = new Handler()
{
#Override
public void handleMessage(Message msg)
{
if (msg.what == SUCCESS)
{
setCalculatedDataToaView(); // the data you calculated from your thread can now be shown in one of your views.
}
else if (msg.what == FAILURE)
{
errorHandlerHere();//could be your toasts or any other error handling...
}
}
};