Chapter 1

Question 1

Activity

Answer 1

instance of Activity, a class in the Android SDK. Responsible for managing user interactions with a screen of information. Main class user see when they run an application. provide gui to the user and this enables user to give and receive to and from an application.

Question 2

Why create subclasses of Activity?

Answer 2

to implement the functionality that your app requires. A simple application may need only one subclass. Complex applications can have many.

Question 3

Layout

Answer 3

set of user interface objects and their position on the screen. A layout is made
up of definitions written in XML. Each definition is used to create an object that appears on
screen, like a button or some text.

Question 4

Relationship between Activity and activity.xml

Answer 4

Activity manages what activity.xml defines

Question 5

Android project

Answer 5

contains the files that make up an application.

Question 6

why are packages uses a reserved DNS?

Answer 6

keeps package names unique and distinguish applications from each other on a device and on google play.

Question 7

The different panes of the workbench window are called views (True/False)

Answer 7

True

Question 8

Widgets

Answer 8

building blocks you use to compose a user interface.A widget can show text or
graphics, interact with the user, or arrange other widgets on the screen. Buttons, text input controls, and
check boxes are all types of widgets.

Question 9

Every widget is an instance of the view class or on of its subclasses (such as textview or button) (True/False)

Answer 9

True

Question 10

purpose of string resource

Answer 10

a file in xml that is used as string references

Question 11

How do XML elements in activity_quiz.xml become view objects?

Answer 11

none

Question 12

purpose of onCreate(Bundle)

Answer 12

method called on when an instance of activity is created. it needs a user interface to manage so it calls the Activity method: setContentView(int layoutResID)

Question 13

public void setContentView(int layoutID);

Answer 13

used to inflate a layout and puts it on screen. when a layout is inflated, each widget in the layout file is instantiated as defined by its attributes by the LayoutInflator class. attributes allow you to configure a widget.

Question 14

resource ID

Answer 14

specifies which layout to inflate.

Question 15

organizing imports

Answer 15

ask eclipse to look at your code and determine what you need from the java and android SKD’s. it imports what you need and removes any previously imported classes that you are no longer using.

Question 16

what does it mean to say android applications are typically event-driven?

Answer 16

driven applications start and then wait for an event, such as the user pressing a button.

Question 17

toast

Answer 17

short message that informs the user of something but does not require any input or action.

Question 18

In makeToast(..), you pass the instance of QuizActivity as the Context argument. Why cant you simply pass the ‘this’ isntead of QuizActivity.this?

Answer 18

At this point in the code, you are defining the anonymous class where this refers to the View.OnClickListener.