I have a simple program with one TextView and two Buttons: Button1 and Button2.
Clicking on Button 1 will start a counter, increasing by 1 every 1 second and show result on TextView; clinking on Button 2 will stop it. Here is a part of my code for Button1. But it does not work.
Timer T=new Timer();
T.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
myTextView.setText("count="+count);
count++;
}
}, 1000, 1000);
I know that there are some similar questions about this using Thread but it seems like they do not mention about stopping the counter.
Any suggestion is really appreciated.
Added:
Hello, I just shortened my code just to this from a much bigger program, but it is still crashed:
package com.example.hello;
import java.util.Timer;
import java.util.TimerTask;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;
public class MainActivity extends Activity {
TextView myTextView;
int count=0;
Timer T;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myTextView=(TextView)findViewById(R.id.t);
T=new Timer();
T.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
myTextView.setText("count="+count);
count++;
}
}, 1000, 1000);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}
The log file (I do not want to post this because it is too long but someone requested it):
07-28 17:35:07.012: W/dalvikvm(11331): threadid=7: thread exiting with uncaught exception (group=0x4001d800)
07-28 17:35:07.016: E/AndroidRuntime(11331): FATAL EXCEPTION: Timer-0
07-28 17:35:07.016: E/AndroidRuntime(11331): android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.ViewRoot.checkThread(ViewRoot.java:2802)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.ViewRoot.requestLayout(ViewRoot.java:594)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.View.requestLayout(View.java:8125)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.View.requestLayout(View.java:8125)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.View.requestLayout(View.java:8125)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.View.requestLayout(View.java:8125)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.widget.RelativeLayout.requestLayout(RelativeLayout.java:254)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.view.View.requestLayout(View.java:8125)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.widget.TextView.checkForRelayout(TextView.java:5378)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.widget.TextView.setText(TextView.java:2688)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.widget.TextView.setText(TextView.java:2556)
07-28 17:35:07.016: E/AndroidRuntime(11331): at android.widget.TextView.setText(TextView.java:2531)
07-28 17:35:07.016: E/AndroidRuntime(11331): at com.example.hello.MainActivity$1.run(MainActivity.java:21)
07-28 17:35:07.016: E/AndroidRuntime(11331): at java.util.Timer$TimerImpl.run(Timer.java:289)
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