APCSP Unit 3 Study guide

What does the TextToSpeech component do?

Converts text to speech

By default, how are components laid out in App Inventor

vertically

What does Fill Parent do?

In the width property, it will fill the container

Can you pass values of property from one object to another?

No

List two valid App Inventor variable names

firstName lastName

Write code to set global X to 18 and increase it by 10

initialize global x to 18. Set global x to get global x +10

What does the Accelerometer Sensor do?

Generates a shaking event

What is an event handler?

A block of code that reacts to an event

What type of data must a global destination variable be if it uses a ListPicker?

List

What is true about data compression?

There are trade-offs involved in choosing which technique to use.

In the app where a user enters a number for the month of the year, what would be appropriate boundary values to check?

0 and 1 + 12 and 13

Define refactoring

Restructuring a program to make it efficient without changing its basic behavior.

How would you name a button that is used to clear the screen?

ButtonRefresh or RefreshButton

What is a variable?

An abstract symbol that refers to some particular value

Why is using a variable an example of abstraction?

A variable is more general and more abstract than specific values such as “ABC”

What is true about a TinyDb component?

Data stored in a TinyDb will persist between different uses of the app.

A digital photo file contains data representing the level of red, green, and blue for each pixel in the photo. The file also contains metadata that describes the date and geographic location where the photo was taken. For what goal would analyzing the metadata be more appropriate than analyzing the data?

Determining the likelihood that the photo was taken at a particular public event.

Define algorithm

a formula or set of steps for solving a particular problem

Define analog

A device or system that represents changing values as continuously variable physical quantities.

Define cloud computing

sharing resources rather than having local server handle apps

Define cryptography

protecting information by transforming it into an unreadable format

Define lossless

a data compression technique in which no data is lost.

Define lossy

a data compression technique in which some amount of data is lost.

Define a megabyte

a unit for characterizing the amount of data. It is 1,048,576 bytes.

Define a megapixel

one million pixels, used in reference to the resolution of a graphics device.

Define modeling

representing a real-world object as a set of mathematical equations.

What is optical character recognition (OCR)?

reading text from paper and translating the images so the computer can manipulate it.

Define persistence

The ability to store data permanently

What is a pixel?

Short for picture element, a single point in a graphic image.

What is ASCII?

A coding system for representing English characters as numbers with each letter assigned a number from 0 to 127.

Define raster

A rectangular area of a display screen actually being used to display images.

Define render

T adding realism to a computer graphic by adding 3D qualities

Define spam

Electronic junk mail

Define stenography

Hiding information by embedding messages within each other, seemingly harmless messages.

What does it mean to upload?

Transmitting data from a computer to a bulletin board service, mainframe, or network.

What is the difference between a GET block and a SET block? *short response*

The get block “gets” the current value. The set block changes or “sets” the value

What are filename extensions *short response*

Describe the contents of a file, and tell the computer operating system what program to open