Timer task TimerTask run cancel Android example
Update TextView from TimerTask, Handler, schedule, run, cancel TimerTask, Android example
public class TimerActivity extends Activity {
TimerTask mTimerTask;
final Handler handler = new Handler();
Timer t = new Timer();
TextView hTextView;
TableRow hTableRow;
Button hButton, hButtonStop;
private int nCounter = 0;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
hTextView = (TextView)findViewById(R.id.idTextView);
hButton = (Button)findViewById(R.id.idButton);
hButton.setOnClickListener(mButtonStartListener);
hButtonStop = (Button)findViewById(R.id.idButtonStop);
hButtonStop.setOnClickListener(mButtonStopListener);
} // end onCreate
View.OnClickListener mButtonStartListener = new OnClickListener() {
public void onClick(View v) {
doTimerTask();
}
};
View.OnClickListener mButtonStopListener = new OnClickListener() {
public void onClick(View v) {
stopTask();
}
};
public void doTimerTask(){
mTimerTask = new TimerTask() {
public void run() {
handler.post(new Runnable() {
public void run() {
nCounter++;
// update TextView
hTextView.setText("Timer: " + nCounter);
Log.d("TIMER", "TimerTask run");
}
});
}};
// public void schedule (TimerTask task, long delay, long period)
t.schedule(mTimerTask, 500, 3000); //
}
public void stopTask(){
if(mTimerTask!=null){
hTextView.setText("Timer canceled: " + nCounter);
Log.d("TIMER", "timer canceled");
mTimerTask.cancel();
}
}
}
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Rozlišení fotoaparátu 8 Mpix
HD video, natačení videosekvencí
Operační system Android
Hlasové ovládání
Přehrávání MP3
Baterie Li-Ion ,doba hovoru 1570 min
Frekvence procesoru 1.4 GHz
Uživatelská paměť 16000 MB
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Podporované sítě GSM&EDGE 850 / 900 / 1.800 / 1.900
Formát videosouborů 3GPP / H.263 / H.264 / MPEG4 / WMV
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E/AndroidRuntime(330): FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{b.paint/b.paint.MainActivity}: java.lang.NullPointerException: println needs a message
Try this code:
E/AndroidRuntime(330): FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{b.paint/b.paint.MainActivity}: java.lang.NullPointerException: println needs a message
Try this code:
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TextView txtV;
Context cntx;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
txtV = (TextView)findViewById(R.id.idLabel);
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conexion.setReadTimeout(1000);
conexion.connect();
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.openStream());
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byte[] byteArray = new byte[1024];
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byteArray = new byte[1024];
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Editace: 2011-10-03 13:57:17
Počet článků v kategorii: 396
Url:timer-task-timertask-run-cancel-android-example