Change TextView value every second? (Android) - android

Hey guys I'm making an android app and all i need to do is update a TextView box (Id: timeText) +1 every second. There are other posts about this but for some reason nothing is working with my code. I've done this in other IDE's but it just doesn't seem to be working with Android Studio.
Here is what i have:
int value = 0;
public MainActivity() {
final TextView TimeText = (TextView) findViewById(R.id.timeText); //giving me error here i think
Timer timer = new Timer();
TimerTask task = new TimerTask()
{
public void run()
{
value++;
TimeText.setText(String.valueOf(value));
}
};
timer.scheduleAtFixedRate(task,0,1000); //1000ms = 1 sec
}
I've been trying to solve this all day and any help would be so greatly appreciated!

Try this method:
final Runnable refresh = new Runnable() {
#Override
public void run() {
// update your TextView
}
};
Thread updateThread = new Thread() {
#Override
public void run() {
try {
while (!isInterrupted()) {
Thread.sleep(1000);
runOnUiThread(refresh);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
updateThread.start();

Related

Update TextView every second in Android [duplicate]

This question already has answers here:
Update TextView Every Second
(11 answers)
Closed 4 years ago.
i want to update my textview every second.
on button click i am calling one method,
loopMethod(milli); //suppose milli= 50000 i.e 50 sec.
so my loopMethod(int m) is as follows:
public void loopMethod(int m){
timer=(TextView) findViewById(R.id.timerText);
if(m>=1000){
try {
timer.setText(""+m);//timer is a textview
System.out.println(m);
m=m-1000;
Thread.sleep(1000);
} catch(InterruptedException ex) {
ex.printStackTrace();
}
loopMethod(m);
}
}
so what i am expecting is, my timer textview should print the value of m every second.
but i am getting only console output i.e system.out.println(m)...
printing value on console working fine...
but its not updating my textview at all
You can use following code:
Runnable updater;
void updateTime(final String timeString) {
timer=(TextView) findViewById(R.id.timerText);
final Handler timerHandler = new Handler();
updater = new Runnable() {
#Override
public void run() {
timer.setText(timeString);
timerHandler.postDelayed(updater,1000);
}
};
timerHandler.post(updater);
}
In this line:
timerHandler.post(updater);
time will set for the first time. i.e, updater will execute. After first execution it will be posted after every 1 second time interval. It will update your TextView every one second.
You need to remove it when the activity destroys, else it will leak memory.
#Override
protected void onDestroy() {
super.onDestroy();
timerHandler.removeCallbacks(updater);
}
Hope it will help you.
You should use RxJava library to do so:
Subscription s =
Observable.interval(1, TimeUnit.SECONDS)
.observeOn(AndroidSchedulers.mainThread())
.subscribe(v -> {
// update your ui here
}, e -> {
});
// call when you no longer need an update:
if (s != null && !s.isUnsubscribed()){
s.unsubscribe();
s = null;
}
That's it. Do NOT use .postDelay(), Timer because it is error prone.
You might want to consider using the Chronometer class: https://developer.android.com/reference/android/widget/Chronometer.html
just use timer.start(); on the button click
Using handler can be used like this
TextView timer;
int m =0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
timer=(TextView) findViewById(R.id.timerText);
Handler handler = new UpdateHandler();
m = 10;
handler.sendEmptyMessageDelayed(1, 1000);//start after 1000
}
class UpdateHandler extends Handler{
#Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what) {
case 1:
timer=(TextView) findViewById(R.id.timerText);
timer.setText("Text :" +m);
m = m-1000;
sendEmptyMessageDelayed(1, 1000); //seng again after 1000
//add some stop logic
break;
default:
break;
}
}
}
Try this code Initialize textview in
onCreate
timer=(TextView) findViewById(R.id.timerText);
public void loopMethod(int m){
if(m>=1000){
try {
System.out.println(m);
m=m-1000;
final ScheduledThreadPoolExecutor c = new ScheduledThreadPoolExecutor(1);
c.schedule(new Runnable() {
#Override
public void run() {
timer.setText(""+m);//timer is a textview
c.shutdownNow();
}
}, 1, TimeUnit.SECONDS);
} catch(InterruptedException ex) {
ex.printStackTrace();
}
loopMethod(m);
}
}
I've added some logics to stop the Timer. If you have any qyestion, ask freely
private int m = 0;
private int milliseconds = 1000;
public void loopMethod(int m){
timer=(TextView) findViewById(R.id.timerText);
Timer t = new Timer();
//schedule a timer
t.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
timer.setText(String.valueOf(m));//avoid using composite string in the setText
System.out.println(String.valueOf(m));
//remove from the total the amount of millisecond passed
m=m-milliseconds;
if(m <= milliseconds) { //or <= what you want
//stop the timer repeatitions
t.cancel();
}
}
});
}
//"0" is the amount of time to wait for the timer to start
//"milliseconds" is the duration
},0,milliseconds);
}
Add
For a correct analysis you should add more infos in your question. the problem of not-updating textview might be caused by the setText("" + int) because it's always better to avoid the setText with an int. I edited it with String.valueOf, but if it's not working you should add the xml and the onCreate
Hope this helped
I have created timer for seconds.
public class TimerForSeconds extends AppCompatActivity {
private int seconds = 60;
private TextView tvTimer;
private Handler mHandler;
private Runnable runnable = new Runnable() {
#Override
public void run() {
if(seconds == 0){
mHandler.removeCallbacks(runnable);
}
else{
tvTimer.setText(seconds + "");
seconds--;
mHandler.postDelayed(runnable,1000);
}
}
};
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.test_activity);
tvTimer = (TextView) findViewById(R.id.tv_timer);
mHandler = new Handler();
mHandler.postDelayed(runnable,1000);
}
}
//and also removCallback onDestroy too.

How to make a picture that would be updated every 30 seconds?

How to make a picture that would be updated every 30 seconds ?
ImageView imageView = (ImageView) findViewById(R.id.imageView);
Picasso.with(this).load("http://i.imgur.com/DvpvklR.png").memoryPolicy(MemoryPolicy.NO_CACHE).networkPolicy(NetworkPolicy.NO_CACHE).into(imageView);
You are going to want to use something like a thread to do this.
For example, below your image view:
Runnable imageUpdater = new Runnable() {
#Override
public void run() {
while (true) {
try {
sleep(30000); // 30 seconds in milliseconds
} catch(InterruptedException e) {
// Someone called thread.interrupt() and tried
// to stop the thread executing
return;
}
// Here load the image in the same way as above:
// But you will need to go onto the UI thread first.
image.post(new Runnable() {
public void run() {
Picasso.with(YourActivity.this).load( "http://i.imgur.com/DvpvklR.png").memoryPolicy(MemoryPolicy.NO_CACHE).networkPolicy(NetworkPolicy.NO_CACHE).into(imageView);
}
});
}
}
};
Then you just start the runnable:
Handler handler = new Handler();
handler.post(imageUpdater);
String[] imageLink = {http://i.imgur.com/DvpvklR.png,
http://i.imgur.com/DvpvklR.png, http://i.imgur.com/DvpvklR.png};
int position = 0;
new Timer().scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
runOnUiThread(runnable);
}
}, 30 * 1000, 30*1000);
Runnable runnable = new Runnable() {
#Override
public void run() {
Picasso.with(this).load(imageLink[position%imageLink.length]).memoryPolicy(MemoryPolicy.NO_CACHE).networkPolicy(NetworkPolicy.NO_CACHE).into(imageView);
position++;
}
};
Hope the above code will help you :)

Android Studio, Delay button

int xp = 0;
public void practice(View v){
xp = (xp+50);
TextView tv = (TextView)findViewById(R.id.xp);
tv.setText("XP: " + xp);
}
I'm am new at android and I want my Button to be enabled and when you click it disable it for amount of time . How could I do this? Any examples?
Try this
public void practice(View v){
xp = (xp+50);
yourBtn.setEnabled(false);
handler.postDelayed(myRunnable, YOUR_DELAY);
TextView tv = (TextView)findViewById(R.id.xp);
tv.setText("XP: " + xp);
}
Handler code is :
Handler handler=new Handler();
Runnable myRunnable=new Runnable() {
#Override
public void run() {
// call you delay logic or method here
yourBtn.setEnabled(true);
}
}
Thread btnEnabledThread = new Thread() {
#Override
public void run() {
try {
yourBtn.setEnabled(false);
sleep(1000);
} catch (InterruptedException i) {
} finally {
yourBtn.setEnabled(true);
}
}
};
if you want to disable for 1 sec then use this code
btnEnabledThread.start();

Displaying a stopwatch in an android app in a textView

I have setup a stop watch using the com.apache.commons library and the stop watch seems to work fine. What I don't know how to do is display this stopwatch in a textView in my app. In general, I have no idea how that would work, i.e. How exactly would a stopwatch be displayed in a textView, given that the time on a stopwatch keeps changing constantly? At the moment, I have the code below and it updated the text in the textView every second for about 2 seconds and then I got a weird error. I'm not even sure if this is the right way to go about doing this. Please help!
Timer timer = new Timer();
TimerTask timerTask;
timerTask = new TimerTask() {
#Override
public void run() {
timeText.setText(time.toString());
}
};
timer.schedule(timerTask, 0, 1000);
The error I got after 2 seconds (and it successfully updated the time) was :
"only the original thread that created a view hierarchy can touch its views"
You can only update a TextView on the UI thread.
runOnUiThread(new Runnable() {
#Override
public void run() {
//stuff that updates ui
}
});
Your code becomes
Timer timer = new Timer();
TimerTask timerTask;
timerTask = new TimerTask()
{
#Override
public void run()
{
runOnUiThread(new Runnable()
{
#Override
public void run()
{
timeText.setText(time.toString());
}
});
}
};
timer.schedule(timerTask, 0, 1000);
You may have to do myActivityObject.runOnUiThread() if you're getting an error there.
See this for more detail.
To update a view from another thread, you should use handler.
private void startTimerThread() {
Handler handler = new Handler();
Runnable runnable = new Runnable() {
private long startTime = System.currentTimeMillis();
public void run() {
//Change the condition for while loop depending on your program logic
while (true) {
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
handler.post(new Runnable(){
public void run() {
timeText.setText(time.toString());
}
});
}
}
};
new Thread(runnable).start();
}

Android Textview not Updating

everyone.
I'm trying to make a basic tycoon game for Android
and I'm trying to increment the value of text-views every 5 seconds with a timer,
But the textview doesn't update.
Here's my code so far:
public class Town extends Activity implements OnClickListener {
Timer timer;
TimerTask task;
TextView goldTV;
TextView woodTV;
TextView foodTV;
TextView stoneTV;
TextView cashTV;
int gold = 20;
int wood = 20;
int food = 20;
int stone = 20;
int cash = 200;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_town);
goldTV = (TextView) findViewById(R.id.textView1);
woodTV = (TextView) findViewById(R.id.TextView01);
foodTV = (TextView) findViewById(R.id.TextView02);
stoneTV = (TextView) findViewById(R.id.TextView03);
cashTV = (TextView) findViewById(R.id.TextView04);
timer = new Timer();
task = new TimerTask() {
#Override
public void run() {
gold++;
goldTV.setText(gold);
try {
this.wait(2000);
}
catch (InterruptedException e){
}
}
};
}
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
}
}
In your run() method
#Override
public void run() {
gold++;
goldTV.setText(gold);
try {
this.wait(2000);
}
catch (InterruptedException e){
}
}
You're calling setText(int resId) instead of setText(CharSequence c);
To display the actual integer gold, convert it from int to String
String goldStr = String.valueOf(gold);
goldTV.setText(goldStr);
Your problem is that you are changing the text on something other than the UI thread. Better is to run it on the UI thread. Plus you should convert your number into a string, or else Android will think you are looking for a resource id. Put them both together, and...
task = new TimerTask() {
#Override
public void run() {
gold++;
runOnUiThread(new Runnable(){
public void run(){
goldTV.setText(""+gold);
}
});
try {
this.wait(5000);
}
catch (InterruptedException e){
}
}
};
Or even better, you could use a handler, like this:
Handler handler = new Handler();
Runnable task=new Runnable(){
public void run(){
handler.postDelayed(this,5000);
goldTV.setText(""+gold);
}
});
handler.postDelayed(task,5000);
a TimerTask should be used with a Timer object. in your code you never run the task.
edit:
try this instead:
goldTV.postDelayed(new Runnable() {
#Override
public void run() {
gold++;
goldTV.setText(gold+"");
goldTV.postDelayed(this,2000);
}
}, 2000);

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