Why is the button.setText() shows error

Question

I made a function that is called every 1 second and within that function I wrote

myButton.setText("Stop");

now everything works great without that code,but whenever I write this code,the mobile I make my test on shows message "app has stopped working" I've been looking for a solution 3 days now,help will be appreciated!

this is my code

check_time = new TimerTask() {
@Override
                        public void run() {

                                myButton.setText("Stop");

                            Calendar lo_Calender = Calendar.getInstance();
                            int current_h = lo_Calender.get(Calendar.HOUR);
                            int current_m = lo_Calender.get(Calendar.MINUTE);
                            if (H_toWake == current_h && M_toWake == current_m) {
                                out.println("ring");

                                alarm();

                                //return;
                            } else {
                                out.println("no ring!");
                            }
                        }
                    };
                    time.schedule(check_time, 0, 1000);
}

score 4 · Accepted Answer · answered Jun 20 '15 at 00:04

4

You cannot touch UI from background thread. use AsyncTask http://developer.android.com/reference/android/os/AsyncTask.html

answered Jun 20 '15 at 00:04

Helmi

556
2
19

will try and tell you ;) – Eyad Lotfy Jun 20 '15 at 00:08
sorry dude,but should I use include the timed function or the (myButton.setText("Stop")) into the AsyncTasked class? – Eyad Lotfy Jun 20 '15 at 00:12
Refer to this answer http://stackoverflow.com/questions/22890505/running-an-async-task-inside-a-timer-in-android – Helmi Jun 20 '15 at 00:17

score 1 · Answer 2 · answered Jun 20 '15 at 00:07

1

First off- the exact bug should be in your logcat. It will tell you what's going wrong. Look there first, on your own.

In this specific case- TimerTasks act on a separate thread. You can only change the UI on the UI thread. Put that part in a runOnUiThread block and you'll be fine.

answered Jun 20 '15 at 00:07

Gabe Sechan

90,003
9
87
127

will try and tell you ;) – Eyad Lotfy Jun 20 '15 at 00:08

Why is the button.setText() shows error

2 Answers2