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Eclipse.
If install on device signed with proguard *.apk package and try to reinstall it by only signed package get error in parsing the package.
Uninstall the first application with bigger size from device and try install signed package which has a smaller size. Delete from download list previous downloaded *.apk.
This problem occurs when that your downloaded apk file size is less than the
size of the original apk.

Set in AndroidManifest.xml android:theme="@android:style/Theme.NoTitleBar" AndroidManifest.xml example source code.
AndroidManifest.xml

<manifest xmlns:android="//schemas.android.com/apk/res/android"
    package="com.myexample.without_titlebar">
    <application android:label="My app">
      <activity android:name="NoTitleBar"
        android:theme="@android:style/Theme.NoTitleBar"
        android:screenOrientation="portrait"
        android:configChanges="keyboardHidden|orientation">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

Update TextView by runnable. Handler, runnable, timer Android example.

public class TimerActivity extends Activity {
TextView hTextView;
Button hButton, hButtonStop;
private Handler mHandler = new Handler();
private int nCounter = 0;
@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        hTextView = (TextView)findViewById(R.id.idTextView);
        hButton = (Button)findViewById(R.id.idButton);
        hButton.setOnClickListener(mButtonStartListener);
        hButtonStop = (Button)findViewById(R.id.idButtonStop);
        hButtonStop.setOnClickListener(mButtonStopListener);
    } // end onCreate

View.OnClickListener mButtonStartListener = new OnClickListener() {
	public void onClick(View v) {
		try {
			mHandler.removeCallbacks(hMyTimeTask);
         //        Parameters
         //        r  The Runnable that will be executed. 
         //        delayMillis  The delay (in milliseconds) until the Runnable will be executed. 
                       mHandler.postDelayed(hMyTimeTask, 1000); // delay 1 second
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
};


private Runnable hMyTimeTask = new Runnable() {
	   public void run() {
		   nCounter++;
	    	   hTextView.setText("Hallo from thread counter: " + nCounter);
	   }
	}; 
/**
 * 
 */
    View.OnClickListener mButtonStopListener = new OnClickListener() {
    	public void onClick(View v) {
    		 mHandler.removeCallbacks(hMyTimeTask);
    		
    	}
    };
}

main.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="//schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
	android:id="@+id/idTextView"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<Button android:text="Button" 
android:id="@+id/idButton" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content"></Button>
 
 <Button android:layout_width="wrap_content" 
 android:layout_height="wrap_content" 
 android:id="@+id/idButtonStop" 
 android:text="Stop"></Button> 
    
    
</LinearLayout>

GregorianCalendar cal = new GregorianCalendar(); Boolean b = cal.isLeapYear(2012); // true, Android example.

public class MainActivity extends Activity {
TextView txtV;
	Context cntx;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        txtV = (TextView)findViewById(R.id.idLabel);
        cntx = this;
        StringBuilder strBuild = new StringBuilder();
        
         GregorianCalendar cal = new GregorianCalendar();
         Boolean b = cal.isLeapYear(2012); // true
         strBuild.append("Is leap year 2012? " + b + "

");
         b = cal.isLeapYear(2014);         // false
         strBuild.append("Is leap year 2014? " + b + "

");
         
         
         txtV.setText(strBuild);
    }
}

The exact physical pixels per inch of the screen
Get size of pixel
Get DPI
Get count of pixels per inch

        float mXDpi;
        float mYDpi;
           DisplayMetrics metrics = new DisplayMetrics();
            getWindowManager().getDefaultDisplay().getMetrics(metrics);
            mXDpi = metrics.xdpi; // The exact physical pixels per inch of the screen in the X dimension. 
            mYDpi = metrics.ydpi;
          float  mMetersToPixelsX = mXDpi / 0.0254f; // 1 inch == 0.0254 metre
          float  mMetersToPixelsY = mYDpi / 0.0254f;