extends Activity implements Runnable

It's a simple exercise extends Activity implements Runnable.

package com.exercise.AndroidRunnable;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.LinearLayout;
import android.widget.TextView;

public class AndroidRunnable extends Activity implements Runnable{

Thread myThread;
boolean running;
int cnt;

TextView myTextView;

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
      myTextView = (TextView)findViewById(R.id.text);
  }

  @Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
startThread();
}

@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
stopThread();
}

public void startThread(){
running = true;
myThread = new Thread(this);
myThread.start();
cnt = 0;
}

public void stopThread(){
running = false;
boolean retry = true;
while(retry){
 try {
  myThread.join();
  retry = false;
 } catch (InterruptedException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
 }
}
}

@Override
public void run() {
// TODO Auto-generated method stub
while (running){

 try {
  cnt++;
  Thread.sleep(100);
  handler.sendMessage(handler.obtainMessage());
 } catch (InterruptedException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
 }
}
}

Handler handler = new Handler(){

@Override
public void handleMessage(Message msg) {
 // TODO Auto-generated method stub
 //super.handleMessage(msg);
 myTextView.setText(String.valueOf(cnt));
}

};
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  >
<TextView
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="@string/hello"
  />
<TextView
  android:id="@+id/text"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
</LinearLayout>

note: please read volatile in Java, in multithreaded programs.

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