What is a ViewGroup in android?

A ViewGroup is a container to hold views. All the android activities, fragment layouts, etc. are ViewGroups. The ViewGroup classes are extended from Views. They are used as containers on the android app screen.

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 that responds to user inputs. Eg: EditText, Button, CheckBox, etc. ViewGroup is an invisible container of other views (child views) and other ViewGroup. Eg: LinearLayout is a ViewGroup that can contain other views in it.

What is the role of ViewGroup explain?

ViewGroup. A ViewGroup is a special view that can contain other views. The ViewGroup is the base class for Layouts in android, like LinearLayout , RelativeLayout , FrameLayout etc. In other words, ViewGroup is generally used to define the layout in which views(widgets) will be set/arranged/listed on the android screen.

What is Android Lint tool?

The lint tool checks your Android project source files for potential bugs and optimization improvements for correctness, security, performance, usability, accessibility, and internationalization. When using Android Studio, configured lint and IDE inspections run whenever you build your app.

What is EMS in android?

ems is a unit of measurement. The name em was originally a reference to the width of the capital M. It sets the width of a TextView/EditText to fit a text of n ‘M’ letters regardless of the actual text extension and text size. Eg : android:ems Makes the EditText be exactly this many ems wide.

What is LayoutParams in android?

This set of layout parameters defaults the width and the height of the children to ViewGroup. LayoutParams. WRAP_CONTENT when they are not specified in the XML file. TableLayout.LayoutParams. This set of layout parameters enforces the width of each child to be ViewGroup.

What does Match_parent mean in android?

match_parent and fill_parent are same property, used to define width or height of a view in full screen horizontally or vertically. These properties are used in android xml files like this. android:layout_width=”match_parent” android:layout_height=”fill_parent”

Why do we use Android toast?

A toast provides simple feedback about an operation in a small popup. It only fills the amount of space required for the message and the current activity remains visible and interactive. Toasts automatically disappear after a timeout.