Java and android
widget
"ready to use" UI element
Application Programming Interface (API)
A set of software routines that allows one software system to work with another.
Data Encapsulation
A technique for bundling multiple named variables into a single object.
local variable
A variable with local scope is one that can only be seen, used and updated by code within the same scope.
What is aapt
Android Asset Packaging Tool: a tool to help view, create, and update APK
APK
Android Package File. package file format used by the Android operating system
ART
Android runtime. The Dalvik Virtual Machine is in the same level as the Native Libraries and allows every Android app to run its own processes.
primitive data type
Basic items that are not objects.
Heap
Heap is used for dynamic memory allocation.
JDK
Java Development Kit. A software development environment for writing in Java .
JRE
Java Runtime Environment (JRE) This allows you to execute Java programs
JVM
Java Virtual Machine, an interpreter for compiled Java bytecodes.
Objects
Object is a container that gathers together some data and some behavior.
garbage collection
Releases memory that was used for a variable's value
Bytecode
Set of instructions composed of compact numeric codes, constants, and references that can be efficiently processed by an interpreter.
State vs Behavior
States refer to features of an object, and more than likely fields. They differ from behaviors, or methods, the latter describing actions that an entity can take.
Java API
The Java Applications Programming Interface that specifies the wide variety of classes that come with the Java platform.
Event handling
The act of coding events to handle each procedure.
super class
The class that is defined first, and other classes inherit from it
Overloading
The process of using the same operator symbol or identifier to refer to a different function
view
a base class for all UI elements
what is Javac Helloworld.c
a compiler
Reference variables
a data type whose instances are not stored directly in that type
What is a callback function?
a function that is passed to a function as a parameter
variable
a piece of data
instance variable
a variable defined in a class
what is the relationship between a view and a widget
a widget is an extension of a view
override
allows a subclass to provide a specific implementation of a method that is already provided by one of its superclass
event
an action that occurs as a result of the user or another source
what is Java Helloworld
an executable
What is Android?
an operating system which is based on Linux with a Java programming interface for cell/smartphones
why are callback functions important
asynchronous programming, including waiting for a user request
interface (in Java)
collection of abstract methods
Android API
collection of software modules that makeup android sdk
Activity Lifecycle
collection to methods used to transition between activities
Composition
combination of several operations into a single line of code
efficiency
conveying maximum amount of information with minimum level of activity
Why does Android with XML
creating the UI elements
what is an attrabute
describes some charatistic of data
setContentView
displays content for your Activity UI by looking at the view class/.xml
package
is a namespace that organizes a set of related classes and interfaces
why is java slower then native code
it needs a vm to run
activation record
keeps track of values as a program execute
common layouts
linear, relative, and web
what activity methods can be over ridden
onCreate()
what is inflation
parsing XML and turning it into UI-oriented data structures.
parameters
passed by values
Signature of a method
refers to writing the method name with its parameters without the return type of the method. ex function prototype
Activity
represents a single screen with a UI
runtime stack
the area of memory that stores local variables and parameters for active function calls
Activity State
the current run status of an activity ex. START, PAUSE, STOPPED, DESTROYED
inheritance (in Java)
the is a relationship between a more general superclass and a more specialized subclass
Subclass
the subordinate or more specialized class in a generalization/specialization relationship
OnClickListener
used to detect clicks from mouse
class variable
variables declared with the static keyword in a class
viewGroup
viewgroup is a subclass of View and act as a base class for layouts and layouts parameters.