How do I create a CheckBox in XML?
To define the click event handler for a checkbox, add the android:onClick attribute to the <CheckBox> element in your XML layout. The value for this attribute must be the name of the method you want to call in response to a click event. The Activity hosting the layout must then implement the corresponding method.
What is the function of check box?
A checkbox (check box, tickbox, tick box) is a graphical widget that permits the user to make a binary choice, i.e. a choice between one of two possible mutually exclusive options. For example, the user may have to answer 'yes' (checked) or 'no' (not checked) on a simple yes/no question.