Author Archives: jkoder

Android Fragment


A Fragment is a piece of an activity which enable more modular activity design. It will not be wrong if we say, a fragment is a kind of sub-activity. If you want to create multi-UI pane than you should use fragment . Fragment Overview * A fragment has its own layout and its own behaviour with its own life cycle ... Read More »

Android Content Providers


Content providers store and retrieve data and make it accessible to all applications. If you want to make your own data public, you have two options: You can create your own content provider (a ContentProvider subclass) or you can add the data to an existing provider. All Services must be declared in the manifest file. Content Provider Basics * All ... Read More »

Android Service


* A Service is an application which has the ability to run in the background without displaying any user interface. * A Service is a class which derives from * All Services must be declared in the manifest file. * Services run without a dedicated GUI, but, like Activities and Broadcast Receivers, they still execute in the main thread ... Read More »

Android Intent


Intent is the negotiator between two activities or between two applications. It gives the ability to pass messages and data between the two entities. When writing applications for mobile, Intent is very handy, since it gives access to a lot of the OS services like opening the camera, a browser, displaying notifications and so on. Intent Resolution Intents can be ... Read More »

Android View


A view is a single user interface element. Its responsibilities include drawing on a canvas and handling user events. Some Views can contain other Views, these are called view groups. A View is a class which derives from android.view.View. There are already many existing views. The developer can use them or create his own customized view by extending any of ... Read More »

Android Activity Lifecycle Concepts


Activity is the presenter of a single screen in the application. It is the only one who has certain abilities, like displaying Views, menus, alerts and notifications. It also has the ability to open a new Activity, which means opening a new screen. Activity is a class which derives from An application needs to have at least one Activity. ... Read More »

Android Libraries


System C library – a BSD-derived implementation of the standard C system library (libc), tuned for embedded Linux-based devices Media Libraries – based on PacketVideo’s OpenCORE; the libraries support playback and recording of many popular audio and video formats, as well as static image files, including MPEG4, H.264, MP3, AAC, AMR, JPG, and PNG LibWebCore – a modern web browser ... Read More »

What Dalvik VM does


The Dalvik VM takes the generated Java class files and combines them into one or more Dalvik Executable (.dex) files. It reuses duplicate information from multiple class files, effectively reducing the space requirement by half from a traditional .jar file. Google has fine-tuned the garbage collection in the Dalvik VM, but it has chosen to omit a just-in-time (JIT) compiler, ... Read More »

Introduction of Android Architecture


At the core of the Android Platform is Linux kernel version 2.6.29, responsible for device drivers, resource access, power management, and other OS duties. The supplied device drivers include Display, Camera, Keypad, WiFi, Flash Memory, Audio, and IPC (inter process communication). At the next level, on top of the kernel, are a number of C/C++ libraries such as OpenGL, WebKit, ... Read More »

git .gitignore not working

If we come across a situation when we feels that the .gitignore file is not working then you are required to run these below commands- git rm -rf --cached . This removes any changed files from the staging area, then run the below command- git add . After running these above commands, now run the commit command and see the ... Read More »