UI Controls

 

Input controls are interactive elements of an Android application’s user interface. Android offers a wide range of built-in controls such as buttons, text input fields, seek bars, check boxes, toggle buttons, zoom buttons, and many others that help users interact with the app.

 

 

A View is a basic UI component that appears on the screen and allows user interaction. A ViewGroup is a special type of View that acts as a container to hold other Views or even other ViewGroups, helping to organize the layout structure of the user interface.

Android layouts are usually defined using XML files, which provide a clear and readable structure similar to HTML. Below is an example of a simple vertical layout containing a TextView and a Button:

 

       

 

Android provides several UI controls that are commonly used to design graphical user interfaces:

Sr.No.	UI Control	Description
1	TextView	Used to display text on the screen.
2	EditText	A subclass of TextView that allows user text input.
3	AutoCompleteTextView	Displays text suggestions while the user types.
4	Button	A clickable button used to perform an action.
5	ImageButton	A button that displays an image instead of text.
6	CheckBox	Allows users to select one or more options independently.
7	ToggleButton	A button that switches between ON and OFF states.
8	RadioButton	Allows selection between two states: checked or unchecked.
9	RadioGroup	Groups multiple RadioButtons together.
10	ProgressBar	Shows progress of a background task.
11	Spinner	A drop-down list used to select a single value.
12	TimePicker	Allows the user to select a time.
13	DatePicker	Allows the user to select a date.

 

Input controls are created by defining UI elements in an XML layout file and assigning each one a unique ID. This ID helps identify the view within the layout hierarchy.

The syntax for assigning an ID is:

 

android:id="@+id/text_id"

Below is an example of defining a TextView with an ID:

 

   

After defining the control in XML, you can access it in your Activity using findViewById():

 

TextView myText = (TextView) findViewById(R.id.text_id);