runOnUiThread: Update UI Using runOnUiThread

Runs the specified action on the UI thread. If the current thread is the UI thread, then the action is executed immediately. If the current thread is not the UI thread, the action is posted to the event queue of the UI thread.

Example:

RunOnUiThreadExample.java:

package com.imrankhanandroid.runOnUiThreadExmp;

import java.text.DateFormat;
import java.util.Date;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class RunOnUiThreadExample extends Activity {
    /** Called when the activity is first created. */
 TextView txtview;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        txtview=(TextView)findViewById(R.id.txtview);
        myThread();
    }
    public void myThread(){
     Thread th=new Thread(){
      
      @Override
      public void run(){
       try
       {
        while(true)
        {
        Thread.sleep(100);
           RunOnUiThreadExample.this.runOnUiThread(new Runnable() {
            
         @Override
         public void run() {
          // TODO Auto-generated method stub
          String currentDateTimeString = DateFormat.
          getDateTimeInstance().format(new Date());
          txtview.setText(currentDateTimeString);
         }
        });
        }
       }catch (InterruptedException e) {
     // TODO: handle exception
    }
      }
     };
     th.start();
    }
}

main.xml:

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

Download Source Code: RunOnUiThreadExample