Samsung i9250 Galaxy Nexus

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
 */

Link to tutorial

ArrayList Sublist of ArrayList Join two ArrayList Compare ArrayList Initialize ArrayList Loop ArrayList Sort ArrayList Array to ArrayList ArrayList to Array Synchronize ArrayList Serialize ArrayList LinkedList Loop LinkedList Vector ArrayList vs Vector ArrayList vs LinkedList HashMap Loop HashMap Synchronize HashMap Sort HashMap Serialize HashMap ArrayList vs HashMap TreeMap LinkedHashMap HashSet TreeSet LinkedHashSet ArrayList Methods

Terms Screen size, density, density independent pixel, resolution as a picture - pictogram.


Test your knowledge
Q: How to find out the phone screen size?
A: (By length of display diagonale in inch -  Not to measure a diagonal of device!!!)

Q: What resolution has 720 x 1280 display?
A: (921600 pixels)

Q: What does it mean "240 dpi" screen density?
A: (Display have density 240 x 240  dots - "Tri-color LED etc." - per every physical (real) square inch. If you have icon 240x240 pixels, this will just occupy an area of one square inch on the display.)

Q: Phone have screen density 240 dpi. Image for 160 dpi screen density have size 128x 128 pixels. What will be the size of the image for 240 dpi screen density?
A: (Calculate the virtual pixels size.   128 * (240/160)  =  192.  You have to resize image to new size 192 x 192 physical pixels and put into folder drawable-hdpi (high) ~240dpi  for phone with screen density 240 dpi. ) or use density independend pixels 128dp x 128dp.

 

 

Try this source code:

Bitmap myBitmap = BitmapFactory.decodeResource(getResources(),R.drawable.my_image)
.copy(Bitmap.Config.ARGB_8888, true);
Canvas c = new Canvas(myBitmap);
// etc.  ....... 

Issue: Immutable bitmap passed to Canvas constructor
Solution: Bitmap myBitmap = BitmapFactory.decodeResource(getResources(),R.drawable.my_image)
.copy(Bitmap.Config.ARGB_8888, true);

Code look up at the Api Demos

android_fragments arguments attributes - three fragments on screen


android_fragments_alert_dialog


android_fragments_context_menu


android_fragments_custom_animation


android_fragments_dialog


android_fragments_dialog_or_activity


fragment_hide_show


fragment_layout


fragments_list_array


fragment_menu


android_fragments_get_result_from_fragment and tabs in two rows


android_fragments_recive_result


android_fragments_stack


fragment_tabs