I've been very confused about this recently and can't find an answer anywhere.
When programming for android, I want to update a textview every 10 seconds, but how would I go about that? I've seen some samples use "Run()" and "Update()", but that doesn't seem to help when I try it, any ideas?
Right now I have:
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.slideshow);
CONST_TIME = (int) System.currentTimeMillis();
Resources res = getResources();
myString = res.getStringArray(R.array.myArray);
}
public void checkTime(View V){
TextView text = (TextView) findViewById(R.id.fadequote);
CUR_TIME = (int) System.currentTimeMillis();
text.setText(""+(int) (CUR_TIME-CONST_TIME));//Debugs how much time has gone by
if(CUR_TIME-CONST_TIME>10000){
getNextQuote(null); //A function that gets a random quote
CONST_TIME = CUR_TIME;
}
}
I guess what I'm REALLY asking is how do I make checkTime() repeat it-self endlessly until onPause() is called?
What about using a timer?
private Timer timer = new Timer();
private TimerTask timerTask;
timerTask = new TimerTask() {
@Override
public void run() {
//refresh your textview
}
};
timer.schedule(timerTask, 0, 10000);
Cancel it via timer.cancel(). In your run() method you could use runOnUiThread();
UPDATE:
I have a livescoring app, which uses this Timer to update it every 30 sec. It looks like this:
private Timer timer;
private TimerTask timerTask;
public void onPause(){
super.onPause();
timer.cancel();
}
public void onResume(){
super.onResume();
try {
timer = new Timer();
timerTask = new TimerTask() {
@Override
public void run() {
//Download file here and refresh
}
};
timer.schedule(timerTask, 30000, 30000);
} catch (IllegalStateException e){
android.util.Log.i("Damn", "resume error");
}
}
Rather than fuss with a background thread and then runOnUiThread()
, use postDelayed()
, available on any View
, to schedule a Runnable
. That Runnable
can update your TextView
and then schedule itself for the next pass. Using a background thread for the purposes of watching time tick by is a waste.
I agree with Wired00's answer but please follow this order:
//update current time view after every 1 seconds
final Handler handler=new Handler();
final Runnable updateTask=new Runnable() {
@Override
public void run() {
updateCurrentTime();
handler.postDelayed(this,1000);
}
};
handler.postDelayed(updateTask,1000);
incase it helps someone here is an example code using postDelayed()
...
private Handler mHandler = new Handler();
...
// call updateTask after 10seconds
mHandler.postDelayed(updateTask, 10000);
...
private Runnable updateTask = new Runnable () {
public void run() {
Log.d(getString(R.string.app_name) + " ChatList.updateTask()",
"updateTask run!");
// run any code here...
// queue the task to run again in 15 seconds...
mHandler.postDelayed(updateTask, 15000);
}
};
Use a thread. See Painless Threading.
来源:https://stackoverflow.com/questions/4776514/updating-textview-every-n-seconds