getInstance is usually used to help to make just one object and without parse it.
for example, we parse parameter Object like this:

public class GpsData {
VarData vardata;
public GpsData(VarData data){
this.data = vardata;
}
}

Nah, with that situation u MUST parse one by one class that use the target class. How hard your life is.
Now, with the simple method, you can reduce it, and make your life happier than before.

public class VarData {
	private static VarData instance;
	private VarData(){}
	public static VarData getInstance() {
		if (instance == null) {
			instance = new VarData();
		}
		return instance;
	}
}

and you can call (make or use the object) like this:

VarData vardata = Vardata.getInstance();

Nah, you can make your life easier, right?
Okay, that’s all for today….
-xrv-

now, I want to let you know how to change UI inside of thread.
You know, Android UI cannot be executed by the thread WITHOUT add an explain to execute the UI.
because the Thread is the execution program that also run while the main process is run. It would be conflict if the Thread also execute UI when the original THread (UI itself) execute the UI. so, Android prohibit it.
So, how?

you must add this:

runOnUiThread(new Runnable() {
						public void run() {
							// stuff that updates ui
							textInfo = (TextView) findViewById(R.id.txtInfo);
							textInfo.setText(someData);
						}
					});

so, the run thread will be (in this section, I used Timer for Thread)

timer.scheduleAtFixedRate(new TimerTask() {
			public void run() {
				if (running) {
					final String someData = data();
					runOnUiThread(new Runnable() {
						public void run() {
							// stuff that updates ui
							textInfo = (TextView) findViewById(R.id.txtInfo);
							textInfo.setMovementMethod(new ScrollingMovementMethod());
							textInfo.setText(someData);
						}
					});
					try {
						txtWrite = true;
						textInfo = (TextView) findViewById(R.id.txtInfo);
						// textInfo.setText(data());
						// infoActivity.writeScreen();
						// writeScreen();
						System.out.println("IF YOU READ THIS....");
						System.out.println(data());
						writeToFile(info, i); // THREAD FOR WRITE TO FILE
						SendThread(); // THREAD FOR SEND TO SERVER
						i++;
					} catch (IOException e) {
						e.printStackTrace();
					}
				} else {
					System.out.println("IT'S FINISH!");
					finish();
				}
			}
		}, delay, period);

once more, if you initialize variable to the Thread, your variable MUST be FINAL.

final String someData = data();

okay, that’s all today….

I just wonder how people know how to use the strange class.
let’s make an example.

This is the class I got from developer.android, I used Telephony Manager, but you know,,, the calling method is different.

Class Overview
Provides access to information about the telephony services on the device. Applications can use the methods in this class to determine telephony services and states, as well as to access some types of subscriber information. Applications can also register a listener to receive notification of telephony state changes.
You do not instantiate this class directly; instead, you retrieve a reference to an instance through Context.getSystemService(Context.TELEPHONY_SERVICE).
Note that access to some telephony information is permission-protected. Your application cannot access the protected information unless it has the appropriate permissions declared in its manifest file. Where permissions apply, they are noted in the the methods through which you access the protected information.

and from the forum, the way to call the class is:

TelephonyManager telephon = (TelephonyManager)	context.getSystemService(Context.TELEPHONY_SERVICE);

Show device info is the basic to make a android interface application. Actually, you should know the data from Android device due to develop your application. For example, if you want to build memory manager application for Android, you must know the memory condition is, the heap size, the free size of memory, the applications that running and how much its use the memory.

For this post, I want to show you how to show android device info.

As you know, Android needs “listener” to get the data from the device. The listener will give all the value that you need.

package get.info;
import java.io.File;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.os.StatFs;
import android.telephony.PhoneStateListener;
import android.telephony.SignalStrength;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.widget.TextView;
public class Npp_getinfoActivity extends Activity {
	TextView textBatteryLevel = null;
	String batteryLevelInfo = "Battery Level";
	TelephonyManager Tel;
	MyPhoneStateListener MyListener;
	boolean hasSignal = false;
	int signal = 0;
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		textBatteryLevel = (TextView) findViewById(R.id.batterylevel_text);
		registerBatteryLevelReceiver();
		TextView tv1 = (TextView) findViewById(R.id.device_name);
		String str = android.os.Build.MODEL;
		tv1.setText(str);
		MyListener = new MyPhoneStateListener();
		Tel = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
		Tel.listen(MyListener, PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
	}
	@Override
	protected void onDestroy() {
		unregisterReceiver(battery_receiver);
		super.onDestroy();
	}
	private BroadcastReceiver battery_receiver = new BroadcastReceiver() {
		@Override
		public void onReceive(Context context, Intent intent) {
			boolean isPresent = intent.getBooleanExtra("present", false);
			String technology = intent.getStringExtra("technology");
			int plugged = intent.getIntExtra("plugged", -1);
			int scale = intent.getIntExtra("scale", -1);
			int health = intent.getIntExtra("health", 0);
			int status = intent.getIntExtra("status", 0);
			int rawlevel = intent.getIntExtra("level", -1);
			int level = 0;
			// GET STORAGE DEVICE
			File path = Environment.getDataDirectory();
			StatFs stat = new StatFs(path.getPath());
			long blockSize = stat.getBlockSize();
			long availableBlocks = stat.getAvailableBlocks();
			// GET CARRIER NAME
			TelephonyManager manager = (TelephonyManager) context
					.getSystemService(Context.TELEPHONY_SERVICE);
			String carrierName = manager.getNetworkOperatorName();
			// GET IMEI
			TelephonyManager telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
			String imei = telephonyManager.getDeviceId();
			// GET IMSI
			TelephonyManager mTelephonyMgr = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
			String imsi = mTelephonyMgr.getSubscriberId();
			// GET PHONE NUMBER
			TelephonyManager tMgr = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
			String mPhoneNumber = tMgr.getLine1Number();
			// GET SIGNAL STRENGTH
			MyListener = new MyPhoneStateListener();
			Tel = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
			Tel.listen(MyListener, PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
			Bundle bundle = intent.getExtras();
			Log.i("BatteryLevel", bundle.toString());
			if (isPresent) {
				if (rawlevel >= 0 && scale > 0) {
					level = (rawlevel * 100) / scale;
				}
				String info = "Battery Level: " + level + "%n";
				info += ("Technology: " + technology + "n");
				info += ("Plugged: " + getPlugTypeString(plugged) + "n");
				info += ("Health: " + getHealthString(health) + "n");
				info += ("Status: " + getStatusString(status) + "n");
				info += ("n");
				info += ("Device Name: " + android.os.Build.MODEL + "n");
				info += ("Telephone Number: " + mPhoneNumber + "n");
				info += ("Android Version: " + Build.VERSION.RELEASE + "n");
				info += ("Memory Usage: " + memoryUsed() + "bytes n");
				info += ("SDCARD Usage: " + availableBlocks * blockSize + "bytes n");
				info += ("Carrier Name: " + carrierName + "n");
				info += ("IMEI : " + imei + "n");
				info += ("IMSI : " + imsi + "n");
				info += ("n Line1 : " + (tMgr.getLine1Number()));
				info += ("n Network Type : " + (networkType(tMgr.getNetworkType())));
				info += ("n Phone Type : " + (tMgr.getPhoneType()));
				info += ("n SIM COuntry Iso : " + (tMgr.getSimCountryIso()));
				info += ("n SIM serial number : " + (tMgr.getSimSerialNumber()));
				info += ("n Subscribe ID : " + (tMgr.getSubscriberId()));
				info += ("n SIM State : " + (tMgr.getSimState()));
				//info += ("n Cell Location : " + (tMgr.getCellLocation()));
				if (hasSignal) {
					info += ("Signal: " + signal + "n");
				}
				setBatteryLevelText(info);
			} else {
				setBatteryLevelText("Battery not present!!!");
			}
		}
	};
	private String getPlugTypeString(int plugged) {
		String plugType = "Unknown";
		switch (plugged) {
		case BatteryManager.BATTERY_PLUGGED_AC:
			plugType = "AC";
			break;
		case BatteryManager.BATTERY_PLUGGED_USB:
			plugType = "USB";
			break;
		}
		return plugType;
	}
	private String getHealthString(int health) {
		String healthString = "Unknown";
		switch (health) {
		case BatteryManager.BATTERY_HEALTH_DEAD:
			healthString = "Dead";
			break;
		case BatteryManager.BATTERY_HEALTH_GOOD:
			healthString = "Good";
			break;
		case BatteryManager.BATTERY_HEALTH_OVER_VOLTAGE:
			healthString = "Over Voltage";
			break;
		case BatteryManager.BATTERY_HEALTH_OVERHEAT:
			healthString = "Over Heat";
			break;
		case BatteryManager.BATTERY_HEALTH_UNSPECIFIED_FAILURE:
			healthString = "Failure";
			break;
		}
		return healthString;
	}
	private String getStatusString(int status) {
		String statusString = "Unknown";
		switch (status) {
		case BatteryManager.BATTERY_STATUS_CHARGING:
			statusString = "Charging";
			break;
		case BatteryManager.BATTERY_STATUS_DISCHARGING:
			statusString = "Discharging";
			break;
		case BatteryManager.BATTERY_STATUS_FULL:
			statusString = "Full";
			break;
		case BatteryManager.BATTERY_STATUS_NOT_CHARGING:
			statusString = "Not Charging";
			break;
		}
		return statusString;
	}
	private void setBatteryLevelText(String text) {
		textBatteryLevel.setText(text);
	}
	private void registerBatteryLevelReceiver() {
		IntentFilter filter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
		registerReceiver(battery_receiver, filter);
	}
	static long memoryUsed() {
		return runtime.totalMemory() - runtime.freeMemory();
	}
	static final Runtime runtime = Runtime.getRuntime();
	// get signal strength
	private class MyPhoneStateListener extends PhoneStateListener {
		@Override
		public void onSignalStrengthsChanged(SignalStrength signalStrength) {
			signal = signalStrength.getGsmSignalStrength();
			System.out.println("SIGNAL: " + signal);
			hasSignal = true;
			// }
		}
	}
	private String networkType(int network) {
		switch (network) {
		case 7:
			return ("1xRTT");
		case 4:
			return ("CDMA");
		case 2:
			return ("EDGE");
		case 14:
			return ("eHRPD");
		case 5:
			return ("EVDO rev. 0");
		case 6:
			return ("EVDO rev. A");
		case 12:
			return ("EVDO rev. B");
		case 1:
			return ("GPRS");
		case 8:
			return ("HSDPA");
		case 10:
			return ("HSPA");
		case 15:
			return ("HSPA+");
		case 9:
			return ("HSUPA");
		case 11:
			return ("iDen");
		case 13:
			return ("LTE");
		case 3:
			return ("UMTS");
		case 0:
			return ("Unknown");
		}
		return "GAGAL";
	}
}

and don’t forget to add the permission on your Android Manifest.

and the result will be like this: