CamelCase (camel case, camel caps or medial capitals) is the practice of writing compound words or phrases such that each next word or abbreviation begins with a capital letter. Camel case may start with a capital or, especially in programming languages, with a lowercase letter.

      public static String UppercaseFirstLetters(String str) {  
           boolean prevWasWhiteSp = true;  
           char[] chars = str.toCharArray();  
           for (int i = 0; i < chars.length; i++) {  
                if (Character.isLetter(chars[i])) {  
                     if (prevWasWhiteSp) {  
                          chars[i] = Character.toUpperCase(chars[i]);  
                     }  
                     prevWasWhiteSp = false;  
                } else {  
                     prevWasWhiteSp = Character.isWhitespace(chars[i]);  
                }  
           }  
           return new String(chars);  
      }  

Introduction 
                         POJO (Plain Old Java Object), basically a class with attributes and it’s getters and setters. The name is used to emphasise that a given object is an ordinary Java Object, not a special object.

Why used in android?
                         POJO is mainly used to denote a Java object which does not follow any of the major Java object models, conventions, or frameworks. Mainly used in Restful API web-services.

Example 
Initialize : 

 public Test(String id, String name) {  
           this.name = name;
           this.id = id; 
      }  

Getter : 

 public String getName() {  
           return name;  
      }  

Setter : 

 public void setName(String name) {  
           this.name = name;  
      }  

Calling from Activity : 

 Test pojo = new Test("001" , "Kumar"};  

Introduction 
                Android is an Operating System for mobile devices developed by Google, which is built upon Linux kernel. Android was developed by the Open Handset Alliance, led by Google, and other companies.

Needs

• Windows / Mac OS / Linux
• Intermediate knowledge in Java Programming
• Java JDK (Download from here)
• Android SDK
• Eclipse

Development Environment
              The Android SDK provides the tools and APIs necessary to begin developing applications on the Android platform using the Java programming language. Download SDK bundle from here. The ADT Bundle includes below things:

• Eclipse + ADT plugin
• Android SDK Tools
• Android Platform tools
• Latest Android platform
• Latest Android image for the emulator

Android online programming classes starts from today. Beginners, Experienced and Job-seekers all will get benefit from this classes.

All Classes will contain intro,programming logic,examples and exercises. All classes in separate label named Android Lessons.

Intro:
finish() it lets system to know that the developer wants the Activity to be finish, after finish it calls ondestroy() 

ondestroy() is for final cleanup ie.

• closing open connections,readers,writers
• dismiss any dialog the activity was running
• close any cursors the activity was running

finish current activity:
To finish current activity use finish() in Intent.

 Intent intent = new Intent(FirstActivity.this, SecondActivity.Class);  
 intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);  
 startActivity(intent);  
 finish();   

finish firstactivity from secondactivity:
To finish any Activity from another Activity (ie.Firstactivity.class from SecondActivty.class)
FirstActivity.class

 public static Activity firstIntent;  

in onCreate() function

 firstIntent = this;  

SecondActivity.class

 firstIntent.finish();  

Now firstactivity.class will finished from secondactivity.class.

Customize setError with common function to use it in any actvity.

 public void setError(EditText edit,String str){  
      int resId = this.getResources().getIdentifier(str, "string", this.getPackageName());  
      String msg = getResources().getString(resId);  
      edit.setFocusableInTouchMode(true);  
      edit.requestFocus();  
      edit.setError(msg);  
 }  

To clear error from EditText / TextView use this

 public void clearError(EditText edit){  
      edit.setError(null);  
      edit.clearFocus();  
 }  

Android OpenSource Libraries for Developers - Java2s

Android Views

Android Custom Views

Android apps:

Libraries for developers

DevAppsDirect