Lesson 1

Question 1

Project Structure (cmd ;), ->app -> flavors

Answer 1

versions

Question 2

AVD

Answer 2

Android Virtual Device

Question 3

stack

Answer 3

application layer, application framework, c/c++ libs & Android Runtime, Linux Kernel

Question 4

ADB

Answer 4

Android Debug Bridge

Question 5

ADB commands

Answer 5

push, pull, shell, logcat…

Question 6

gradle task

Answer 6

atomic work for build

Question 7

./gradlew tasks

Answer 7

run on command line to list runnable gradle tasks

Question 8

adb list commands

Answer 8

enter adb into terminal

Question 9

Apps are…

Answer 9

collections of connected components

Question 10

4 types of app components

Answer 10

Activity, Service, Content Provider, Broadcast Receiver (BACS) | (Br, A,S,Cp)

Question 11

Android Manifest does what with components?

Answer 11

Register components

Question 12

Activity

Answer 12

Component responsible for user interaction (view); a “single focused thing the user can do”.
Responsible for creating the window the application uses to draw and receive events from the system.

Question 13

Experience of App, Activities

Answer 13

Experience app as a sequence of activities, beginning with launcher. Kept as a stack.

Question 14

Android Manifest’s launcher

Answer 14

launch tag for application. Registered to an activity, with an intent filter for launching.

Question 15

what layout does for activity

Answer 15

layout contains information about what to display, and how to display it.

Question 16

res folder

Answer 16

application resources

Question 17

resources

Answer 17

strings, images, files, layouts

Question 18

layout file

Answer 18

xml format, contains view objects

Question 19

onCreate in java activity, layout

Answer 19

setContentView to some layout; “inflates layout… Android reads your XML file and generates Java objects for each of the tags in your layout file”; i.e. instantiates layout

Question 20

views

Answer 20

created by activity to show information, and be interacted with. Rectangular area responsible for drawing and handling events.

Question 21

xml layout file; for activity, stored where

Answer 21

how an activity determines what views to create + where to put them. Stored in res folder “layouts”

Question 22

UI components

Answer 22

view type that’s often interacted with. E.g. TextView, EditText, ImageView, Button, Chronometer

Question 23

Layout/Container_View

Answer 23

typically contain group of views, determine position. E.g. LinearLayout, RelativeLayout, FrameLayout, ScrollView, ConstraintLayout

Question 24

wrap_content

Answer 24

shrink view to wrap whatever is inside the view

Question 25

match_parent

Answer 25

expand view to parent’s size

Question 26

app/build.gradle

Answer 26

contains dependencies; eg. dependency for constraint layout: “com.android.support.constraint:constraint-layout:1.0.0-beta4”. In Gradle scripts.

Question 27

where to instantiate TextView?

Answer 27

inside activity’s java, after inflating a layout with that TextView

Question 28

how to connect inflated TextView with activity code?

Answer 28

1. use id
2. declare TextView as property of class,
3. inflate layout with TextView
   in OnCreate: setContentView(R.layout.activity_main);
4. in onCreate, set TextView to id:
   “findViewById(R.id.tv_toy_names)”

Question 29

layout id syntax

Answer 29

e.g.: “@+id/tv_toy_names”

@ : “treat stuff inside quotes as not a string literal, but look for contents inside Android Resources.
+ : create id if doesn’t already exist
id : creating an id, not reference (style, string, image)

creates an id inside Resources, where above becomes R.id.tv_toy_names

Question 30

steps to add TextView

Answer 30

1. add ID to TextView in layout
2. Find ID for TextView in MainActivity.javasource
3. Append the contents to TextView

Question 31

Array syntax Java

Answer 31

String[]

Question 32

for-each loop Java syntax

Answer 32

for (   : ) {
// do thing with item
}

Question 33

xml syntax

Answer 33

TODO (?)

Question 34

widgets

Answer 34

single-purpose views, such as buttons, edit-text

Question 35

constraint layout - special layout how?

Answer 35

uses constraints to allow for dynamic layouts; different window sizes

Question 36

Why LinearLayout, GridLayout, ConstraintLayout?

Answer 36

No absolute layout; dynamic size. Follow principles of “responsive design”

Question 37

FrameLayout for?

Answer 37

only one child view; like a listview that fills content area. Put in corners

Question 38

LinearLayout for?

Answer 38

Stack views vertically or horizontally

Question 39

ConstraintLayout for?

Answer 39

Complex, powerful. Figure out each view’s position specifically.

Question 40

XML Framelayout

Question 41

constraint layout dependency

Answer 41

remove/add “implementation ‘com.android.support.constraint:constraint-layout:1.1.3’” in build.gradle.dependencies

Question 42

Java Array init with values

Answer 42

{“str1”, “str2”, “str3”};

Question 43

Getting inflated layout views in OnCreate

Answer 43

Class {
    property;
    OnCreate(){
        property ()
    }
}

Question 44

setContentView?

Answer 44

in onCreate, setContentView to xml file