Develop Reference

How to add wait time?

The backgrounds of all the pictures are changing at the same time. I have to change one by one, wait 5 seconds after each picture, change the other,
ImageView[] imajlar={img1,img2,img3,img4,img5,img6,img7,img8};
for (final ImageView resmi:imajlar) {
//resmi.startAnimation(fadeout);
new CountDownTimer(16000, 1000) {
#Override
public void onTick(long millisUntilFinished) {
resmi.setBackground(hediye);
resmi.startAnimation(fadein);
onPause();
}
#Override
public void onFinish() {
}
}.start();

Use Handler for this. I hope this helps you.
new Handler().postDelayed(new Runnable(){
#Override
public void run() {
changeImage();
}
}, 5000);

Try Timer with Handler
Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
//Your code
}
}, 0, 5000);

Try this code..
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
// define your code..
}
},5000);

Do it like
Define an array of images.
String img[]={img1,img2,img3};
and a variable
int i=0;
now in your method
changeImage()
{
if(i<img.length())
{
//Pseudo code(your logic of setting image)
setImage.array[i];
i++;
}
else
{
//This is to start again;
i=0
}
}
Then in you defined handler.
final Handler mHandler=new Handler();
ha.postDelayed(new Runnable() {
#Override
public void run() {
changeImage();
mHandler.postDelayed(this, 5000);
}
}, 5000);

int totalImageSize = yourTotalImageCount;
final Handler mHandler = new Handler();
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
changeYourImage(totalImageSize);// this will give the position of image to add/remove
totalImageSize - 1;
if(totalImageSize > 0)
mHandler.postDelayed(this, 5000);
}
}, 5000);
}

Android studio update textview every 5 seconds

Hi my app needs a realtime data from database and I'm posting it on my TextView and I can't update the TextView as the database updates. I tried using Timer but its still the same.
Here is my code,
public void startTimer() {
//set a new Timer
timer = new Timer();
//initialize the TimerTask's job
initializeTimerTask();
timer.schedule(timerTask, 0, 5000);
}
private void stopTimerTask() {
//stop the timer, if it's not already null
if (timer != null) {
timer.cancel();
timer = null;
}
}
public void initializeTimerTask() {
timerTask = new TimerTask() {
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
final AcceptCars Cars = (AcceptCars) getIntent().getSerializableExtra("cars");
renterLat.setText(Cars.renterLat);
renterLng.setText(Cars.renterLng);
Log.d(TAG,renterLat.getText().toString());
Log.d(TAG,renterLng.getText().toString());
}
});
}
};
}
And here is where I get the Cars.renterLat and Cars.renterLng,
public class AcceptCars implements Serializable {
#SerializedName("renterLat")
public String renterLat;
#SerializedName("renterLng")
public String renterLng;
}

This is the logic you should be following. I used a Handler instead of a Timer. Inside the run method you need to call your webservice and get the updated value from the db. Use runOnUiThread to update the value to the UI from a Thread.
See the code below,
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Handler taskHandler = new Handler();
taskHandler.postDelayed(myTask, 0);
}
private Runnable myTask = new Runnable(){
public void run() {
queryDb();
// repeat the task
taskHandler.postDelayed(this, 1000);
}
};
private void queryDb(){
new Thread(new Runnable() {
#Override
public void run() {
// call you webservice
String data = callWebservice();
// parse the data in to AcceptCars pojo class
AcceptCars Cars = parseData(data);
//update the UI
runOnUiThread(new Runnable() {
#Override
public void run() {
renterLat.setText(Cars.renterLat);
renterLng.setText(Cars.renterLng);
}
});
}
}).start();
}

You can even use countdown timer.
Here is the link https://developer.android.com/reference/android/os/CountDownTimer.html

TimerTasks are really hard to deal with IMO. You should use a Handler and call postDelayed to do something after a certain amount of time.
Alternatively, you can try out this timer class I wrote:
import android.os.Handler;
public class Timer {
private Handler handler;
private boolean paused;
private int interval;
private Runnable task = new Runnable () {
#Override
public void run() {
if (!paused) {
runnable.run ();
Timer.this.handler.postDelayed (this, interval);
}
}
};
private Runnable runnable;
public int getInterval() {
return interval;
}
public void setInterval(int interval) {
this.interval = interval;
}
public void startTimer () {
paused = false;
handler.postDelayed (task, interval);
}
public void stopTimer () {
paused = true;
}
public Timer (Runnable runnable, int interval, boolean started) {
handler = new Handler ();
this.runnable = runnable;
this.interval = interval;
if (started)
startTimer ();
}
}
It is really simple to use.
You can use it like this:
Timer timer = new Timer(new Runnable() {
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
final AcceptCars Cars = (AcceptCars) getIntent().getSerializableExtra("cars");
renterLat.setText(Cars.renterLat);
renterLng.setText(Cars.renterLng);
Log.d(TAG,renterLat.getText().toString());
Log.d(TAG,renterLng.getText().toString());
}
}
}
}, 5000, true);

Timer isn't cancelled by timer.cancel()

My Timer doesn't stop running if I cancel it!
The Timer only stops if I shut down the whole app!
I don't know why the Timer is not cancelled. If I print out every try on cancelling the Timer I get hundrets of lines but the Timer does not stop!
My Class:
public class PlayActivity extends AppCompatActivity
implements View.OnClickListener, SeekBar.OnSeekBarChangeListener, MediaplayerEvent {
//region Activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Initialize_Layout();
Initialize_Objects();
}
#Override
protected void onResume() {
super.onResume();
MusicService.setMediaPlayerEvent(this);
txvSongtitle.setText(serviceInterface.MP_getActualSong().getTitle());
Start_Timer();
}
#Override
protected void onPause() {
timer.cancel();
MusicService.clearMediaPlayerEvent();
super.onPause();
}
#Override
public boolean onSupportNavigateUp() {
finish();
return super.onSupportNavigateUp();
}
//endregion
//region Methods
private void Start_Timer() {
timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
if (serviceInterface.MP_isPlaying()) {
runOnUiThread(new Runnable() {
#Override
public void run() {
seekBar.setMax(serviceInterface.MP_getDuration());
seekBar.setProgress(serviceInterface.MP_getCurrentPosition());
}
});
}
else {
runOnUiThread(new Runnable() {
#Override
public void run() {
timer.cancel();
}
});
}
}
}, 0, 200);
}
#Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
if (fromUser) {
serviceInterface.MP_seekTo(progress);
Start_Timer();
}
}
//endregion
}
I hope you can help me!
Thanks!

I would suggest using a Thread instead of a Timer. Your Start_Timer()code would change to something like the following:
private Thread mTimerThread;
...
private void Start_Timer() {
mTimerThread = new Thread() {
#Override
public void run() {
try {
while (!isInterrupted()) {
if (serviceInterface.MP_isPlaying()) {
runOnUiThread(new Runnable() {
#Override
public void run() {
seekBar.setMax(serviceInterface.MP_getDuration());
seekBar.setProgress(serviceInterface.MP_getCurrentPosition());
}
});
} else {
interrupt();
}
Thread.sleep(200);
}
} catch (InterruptedException e) {
}
}
}
mTimerThread.start();
}
Threads are more efficient and lightweight and perfect for your needs. Plus, by setting the Thread to a global variable, you can make sure to call mTimerThread.interrupt(); during Android lifecycle events, such as onPause().
I hope this fixes your issue. Remember, the Java Thread is your friend!

You're creating and starting a new timer the user moves the seekbar (in onProgressChanged()). That also means you lose the reference to the old one. When isPlaying turns false, all the timers will try to cancel timer -- which only references the most recent one.

Change TextView value using uithread

I'm trying to change some textview value but when it's not appeared on the screen the value don't change or when it's appeared on screen it changes and when scroll down and scroll back up it's value returns to the old one i tried the following two ways but non of them is working :
final Timer timer=new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
MainActivity.this.runOnUiThread(new Runnable() {
#Override
public void run() {
myTextView.setText("sometext");
timer.cancel();
}
});
}
}, 5000, 1000);
and:
MainActivity.this.r1.post(new Runnable() {
public void run() {
myTextView.setText("sometext");
}
});

Try using Handler
private void TestThread() {
Handler handler = new Handler();
Runnable runnable = new Runnable() {
public void run() {
handler.post(new Runnable(){
public void run() {
tvTime.setText("SomeText");
}
});
}
}
};
new Thread(runnable).start();
}
Also you can take a look AsyncTask Documentation and onPostExecute() you set the text to TextView.

You have to make sure that the UI is drawn first before you change the value of the TextView , It can be done by adding a layout listener,
ViewTreeObserver vto = getWindow().getDecorView().getViewTreeObserver();
vto.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Overrid
public void onGlobalLayout() {
final Timer timer=new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
MainActivity.this.runOnUiThread(new Runnable() {
#Override
public void run() {
myTextView.setText("sometext");
timer.cancel();
}
});
}
}, 5000, 1000);
}
}

Invalidate() is not happening from Activity in Timer

This is my code on Activity to Invalidate the canvas it is not invalidating. Means onDraw() is not getting called even once;
public GraphView view;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
view = GraphView(this,null);
runplotTimer();
}
public void runplotTimer()
{
Timer t = new Timer();
//Set the schedule function and rate
t.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
InvalidateTimer();
}
},1000,40);
}
public void InvalidateTimer()
{
this.runOnUiThread(new Runnable() {
#Override
public void run()
{
//Log.d(ALARM_SERVICE, "Timer of 40 miliseconds");
view.InvalidateGraph();
}
});
}
on View class this is method which is gettting called from Activity. other OnDraw declaration is same as required.
public void InvalidateGraph()
{
m_bCalledPlotRealTimeGraph = true;
invalidate(chanX_count1, 0, chanX_count1+7, graphheight);
}
Any help please ?

You are attempting to make changes to the View on a Timer Thread, which will not work. You need to call invalidate on the main (UI) thread:
((Activity) view.getContext()).runOnUiThread(new Runnable() {
#Override
public void run() {
invalidate(chanX_count1, 0, chanX_count1+7, graphheight);
}
});

you need to Start the Timer
Timer t = new Timer();
//Set the schedule function and rate
t.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
InvalidateTimer();
}
},1000,40);
t.start()
Instead of Timer use Handler.
class UpdateHandler implements Runnable {
#Override
public void run(){
handler.sendEmptyMessageAtTime(0, 1000);
handler.postDelayed(this, 1000);
}
}
private Handler handler = new Handler(Looper.getMainLooper()) {
#Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
//Call your draw method
}
}
};
Inside onCreate and onResule write
if( mupdateTask == null )
mupdateTask = new UpdateHandler();
handler.removeCallbacks(mupdateTask);
Call your handler using
handler.postDelayed(mupdateTask, 100);