// public Object getSystemService (String name) 

// Return the handle to a system-level service by name. 

// The class of the returned object varies by the requested name.

InputMethodManager inputMethodManager = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);

//public boolean hideSoftInputFromWindow (IBinder windowToken, int flags) 

//EditText myEdit = (EditText)findViewById(R.id.idEditText);                

inputMethodManager .hideSoftInputFromWindow(myEdit.getWindowToken(), 0);

 Display display = getWindowManager().getDefaultDisplay();
int nWidth = display.getWidth();
int nHeight = display.getHeight();

          DisplayMetrics metrics = new DisplayMetrics();
            getWindowManager().getDefaultDisplay().getMetrics(metrics);
            //get density per inch for example: 120 , 160 , 240
            mXDpi = metrics.xdpi; // 160 The exact physical pixels per inch of the screen in the X dimension. 
            mYDpi = metrics.ydpi;

// density
int nDensity = metrics.densityDpi; // 160 screen density expressed as dots-per-inch

          float  mMetersToPixelsX = mXDpi / 0.0254f; // 1 inch == 0.0254 metre
          float  mMetersToPixelsY = mYDpi / 0.0254f;
          
// Resolution
// The total number of physical pixels on a screen.
int wPix = metrics.widthPixels; // 320 The absolute width of the display in pixels.
int hPix = metrics.heightPixels; // 480 The absolute height of the display in pixels.
int nWidthDisplay = (wPix < hPix)? wPix : hPix;

float nWidthScreenInInch = wPix / mXDpi; //320 / 160 == 2.0 in inch.
float nHeightScreenInInch = hPix / mYDpi; //480 / 160 == 3.0 in inch.

// for example:
// density 120 per inch
//width 320 pix / 120 dpi == width 2.66 inch
//height 480 pix / 120 dpi == height 4.0 inch 

// density 240 per inch
//width 320 pix / 240 dpi == width 1.33 inch
//height 480 pix / 240 dpi == height 2.0 inch 

public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = { "Hello", "people", "hello", "world!" };

		for (int i = 0; // start position , first cycle i == 0
                      i < arrayOfString.length; // if i < 4 (length of array) do loop
                       i++ // incrementation after cycle
                       ){
			System.out.println(arrayOfString[i]); 
                       // i++ incrementation
		}
	}
}

// res/values/strings.xml
<string name="link_text_auto"><b>text1:</b> This is some text.  In
      this text are some things that are actionable.  For instance,
      you can click on //www.google.com and it will launch the
      web browser.  You can click on google.com too.  And, if you
      click on (415) 555-1212 it should dial the phone.
    </string>
// main.xml
<!-- text1 automatically linkifies things like URLs and phone numbers. -->
  <TextView xmlns:android="//schemas.android.com/apk/res/android"
            android:id="@+id/text1"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:autoLink="all"
            android:text="@string/link_text_auto"
            />

// MainActivity.java onCreate
/*Be warned that if you want a TextView with a key listener or movement method not to be focusable, or if you want a TextView without a key listener or movement method to be focusable, you must call setFocusable(boolean) again after calling this to get the focusability back the way you want it. */

TextView t2 = (TextView) findViewById(R.id.text2);
t2.setMovementMethod(LinkMovementMethod.getInstance());

// main.xml
<!-- text2 uses a string resource containing explicit <a> tags to
       specify links. -->
  <TextView xmlns:android="//schemas.android.com/apk/res/android"
            android:id="@+id/text2"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:text="@string/link_text_manual"
            />

//strings.xml

<string name="link_text_manual"><b>text2:</b> This is some other
      text, with a <a href="//www.google.com">link</a> specified
      via an <a> tag.  Use a "tel:" URL
      to <a href="tel:4155551212">dial a phone number</a>.
    </string>

// MainActivity.java onCreate
        TextView t3 = (TextView) findViewById(R.id.text3);
        t3.setText(
            Html.fromHtml(
                "<b>text3:</b>  Text with a " +
                "<a href="//www.google.com">link</a> " +
                "created in the Java source code using HTML."));
        t3.setMovementMethod(LinkMovementMethod.getInstance());

        SpannableString ss = new SpannableString(
            "text4: Click here to dial the phone.");

        ss.setSpan(new StyleSpan(Typeface.BOLD), 0, 6,
                   Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        ss.setSpan(new URLSpan("tel:4155551212"), 13, 17,
                   Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);

        TextView t4 = (TextView) findViewById(R.id.text4);
        t4.setText(ss);
        t4.setMovementMethod(LinkMovementMethod.getInstance());