What is view and ViewGroup in Android?

View is a basic building block of UI (User Interface) in android. A view is a small rectangular box which responds to user inputs. Eg: EditText , Button , CheckBox , etc.. ViewGroup is a invisible container of other views (child views) and other viewgroups.

What are view and ViewGroup classes in Android?

View is the base class for widgets, which are used to create interactive UI components like buttons, text fields, etc. The ViewGroup is a subclass of View and provides invisible container that hold other Views or other ViewGroups and define their layout properties.

What is the main purpose of ViewGroup?

What is the main purpose of a ViewGroup? It groups together the most common views that developers use in Android apps. It serves as a container for View objects, and is responsible for arranging the View objects within it. It is required to make a view interactive as a way to group TextViews on a screen.

What is a view in Android?

View is the basic building block of UI(User Interface) in android. View refers to the android. It can be an image, a piece of text, a button or anything that an android application can display. … The rectangle here is actually invisible, but every view occupies a rectangle shape.

What is view in Android with example?

The View is a base class for all UI components in android. For example, the EditText class is used to accept the input from users in android apps, which is a subclass of View . Following are the some of common View subclasses that will be used in android applications.

What is the use of ConstraintLayout in Android?

Android Constraint Layout Overview

Android ConstraintLayout is used to define a layout by assigning constraints for every child view/widget relative to other views present. A ConstraintLayout is similar to a RelativeLayout, but with more power.

What are the types of layouts in Android?

Types of Layouts in Android

  • Linear Layout.
  • Relative Layout.
  • Constraint Layout.
  • Table Layout.
  • Frame Layout.
  • List View.
  • Grid View.
  • Absolute Layout.

What is Clipchildren?

2, can through android:layout_gravity control over how the part of the display. … 3, Android:clipchildren meaning: whether to limit the child view within its scope.

What is the use of linear layout in Android?

LinearLayout is a view group that aligns all children in a single direction, vertically or horizontally. You can specify the layout direction with the android:orientation attribute. Note: For better performance and tooling support, you should instead build your layout with ConstraintLayout.

What is the fragment life cycle in Android?

A fragment can be used in multiple activities. Fragment life cycle is closely related to the life cycle of its host activity which means when the activity is paused, all the fragments available in the activity will also be stopped. A fragment can implement a behaviour that has no user interface component.

What is the use of OnClickListener in Android?

In Android, the OnClickListener() interface has an onClick(View v) method that is called when the view (component) is clicked. The code for a component’s functionality is written inside this method, and the listener is set using the setOnClickListener() method.

What is the use of findViewById in Android?

findViewById is the method that finds the View by the ID it is given. So findViewById(R. id. myName) finds the View with name ‘myName’.

What are the 4 types of app components?

There are four different types of app components:

  • Activities.
  • Services.
  • Broadcast receivers.
  • Content providers.

What is setOnClickListener in Android?

One of the most usable methods in android is setOnClickListener method which helps us to link a listener with certain attributes. setOnClickListener is a method in Android basically used with buttons, image buttons etc. You can initiate this method easily like, public void setOnClickListener(View.OnClickListner)

How do I use getTag on Android?

How to use getTag method in android.widget.TextView

  1. Context context;new TextView(context)
  2. View view;(TextView) view.findViewById(id)
  3. View view;view.findViewById(id)

What is an Inflater in Android?

What is an Inflater ? To summarize what the LayoutInflater Documentation says… A LayoutInflater is one of the Android System Services that is responsible for taking your XML files that define a layout, and converting them into View objects. The OS then uses these view objects to draw the screen.

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