View View objects are the basic building blocks of User Interface(UI) elements in Android. View is a simple rectangle box which responds to the user's actions. Examples are EditText , Button , CheckBox etc.. View refers to the android.view.View class, which is the base class of all UI classes. ViewGroup ViewGroup is the invisible container. It holds View and ViewGroup For example, LinearLayout is the ViewGroup that contains Button(View), and other Layouts also. ViewGroup is the base class for Layouts.
W hile developing Android applications, we all see and use the term context. But for most new programmers its a nightmare to resolve a context related error. This post helps you understand what context really means in Android Context in Android is an interface to global information about an application environment. This is an abstract class whose implementation is provided by the Android system. It allows access to application-specific resources and classes, as well as up-calls for application-level operations such as launching activities, broadcasting and receiving intents, etc. Every boss has an assistant to look after, to do all less important and time consuming tasks. If a file or a cup of coffee is needed, assistant is on the run. Some bosses barely know what’s going on in the office, so they ask their assistants regarding this too. They do some work themselves but for most other things they need help of their assistants. In this scenario, Boss – is the Androi...
An Android activity is one screen of the Android app's user interface. In that way an Android activity is very similar to windows in a desktop application. An Android app may contain one or more activities, meaning one or more screens. The Android app starts by showing the main activity, and from there the app may make it possible to open additional activities. Activity Life Cycle Any Android activity goes through a certain life cycle during its life inside the Android app. This life cycle is illustrated here: When an Android app is first started the main activity is created. The activity then goes through 3 states before it is ready to serve the user: Created, started and resumed. If the main activity can open any other activities (screens) these activities will go through the same 3 states when they are opened. If an activity A opens another activity B, then activity A will be paused. This means that activity A goes into the paused state. When the user clicks ...
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