Android Google Maps Night Mode

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;

Get assets folder files to array of strings.
Its show files in assets folder and sub folders:

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        final AssetManager assetManager = getAssets();
        try {
			// for assets folder add empty string
                        String[] filelist = assetManager.list("");
                        // for assets/subFolderInAssets add only subfolder name
                        String[] filelistInSubfolder = assetManager.list("subFolderInAssets");
			if (filelist == null) {
			    // dir does not exist or is not a directory
			} else {
			    for (int i=0; i<filelist.length; i++) {
			        // Get filename of file or directory
			        String filename = filelist[i];
			    }
			}
                     
                        // if(filelistInSubfolder == null) ............  

		} catch (IOException e) {
			e.printStackTrace();
		}
     }

- create new folder with values in resources folder in project with extension your language code
For example:
My language is Czech (cs)
I have to create the folder values-cs in res folder

// for locale English is default
/MyProject/res/values 
<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">App English default</string>
    <string name="action_settings">Settings English default</string>
    <string name="hello_world">Hello world</string>

</resources>

// for locale Czech (cs)
/MyProject/res/values-cs
<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">Aplikace česky cs</string>
    <string name="action_settings">Nastavení česky</string>
    <string name="hello_world">Ahoj světe!</string>

</resources>

// for locale English US (r is region)
/MyProject/res/values-en-rUS

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

    <string name="app_name">App English Us locale</string>
    <string name="action_settings">Settings English Us locale</string>
    <string name="hello_world">Hello world from USA :)</string>

</resources>

Into every values folder put strings.xml file
Translate every string from values folder into your locale.
If user selected your locale in device settings, application selects a string from the correct (proper) folder.

public class ApokusActivity extends Activity {
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {

		// CONSTRUCTOR
		public SampleView(Context context) {
			super(context);
			setFocusable(true);

		}
		@Override
		protected void onDraw(Canvas canvas) {
			Paint paint = new Paint();
			
			canvas.drawColor(Color.GREEN);
            
           Bitmap b = Bitmap.createBitmap(200, 200, Bitmap.Config.ALPHA_8);
           Canvas c = new Canvas(b);
           c.drawRect(0, 0, 200, 200, paint);
           
           paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));
           paint.setTextSize(40);
           paint.setTextScaleX(1.f);
           paint.setAlpha(0);
           paint.setAntiAlias(true);
           c.drawText("Your text", 30, 40, paint);
           paint.setColor(Color.RED);
           
           canvas.drawBitmap(b, 10,10, paint);
		}

	}
}

Map TreeMap add key value pair get find pair by key Java Android example.

MainClass.java

import java.util.Map;
import java.util.TreeMap;

public class MainClass {
	public static void main(String[] arg) {
		
		// english;germany dictionary
		String[] arrayOfString = { "one;eine", "two;zwei", "three;drei" };

		Map<String, String> map = new TreeMap<String, String>();
	    
		for(String s: arrayOfString){
	    	String[] array = s.split(";");
	    	String sKey ="", sValue="";
	    	if(array.length > 1){
	    	sKey = array[0]; sValue = array[1];
	    		map.put(sKey, sValue);
	    	}
	    }

       // check if key exists 	    
	   if( map.containsKey("two")){
		System.out.print("two = " + map.get("two"));
	   }
	}
}
/*
two = zwei
 */