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ICS2O1 Strand 2
ICS2O1 Strand 2 App Inventor
Term | Definition |
---|---|
App Inventor Development Cycle Steps | 1. Design/Redesign 2. Create UI 3. Code blocks 4. Test/Debug |
An event | Doing something in the app such as clicking on a button for example. |
An action | A result of the event happening (i.e. press the button (the event) and display a graphic (the action)). |
IPO | Input, Processing, Output |
Input | An input is information that must be received by the app once it starts. |
Processing | Processing is the action the app must perform to obtain the desired result. |
Output | An output is the information that the app must provide to the user. |
Virtual Machine | A recreation of an environment (say the Andriod phone) in another computing environment (say the PC). |
Algorithm | A list of steps written in English that the program will have to perform. |
Bug | An error which stops your code working as expected. |
Syntax error | The rules of the language have been broken, e.g. by mis-spelling a command. |
Logic error | This means your code runs, but doesn't do what you expect. |
Debugging | Finding and fixing the errors in a program. |
Rubber Duckie | The process of talking about what your code SHOULD do while comparing it to what it ACTUALLY does. Note, you don't need a real rubber duckie to do this! |
Variable | A space in a computer's memory where we can hold information used by our program |
Number variable | Can contain whole numbers or decimal numbers |
String variable | Can contain text, characters, or numbers but surrounded by " ". |
Boolean variable | Can contain either true or false. |
Mathematic operators | Perform a calculation. Found in the Math blocks. Examples: add, subtract, multiply, divide, and exponents. |
Joining strings | Can be done with the join block (see ai2 codes) |
Sprite | A 2D image inserted into a larger screen. |
Procedure | Very useful in coding. Eliminates repetitive codes. Lets us break a problem down into smaller problems and solve each one separately. |
If Block | Found under Controls. Allows for one branch. Here's how it works: If <condition is true> then do some sort of action (code) |
Condition | A statement that results in either two outcomes (true or false, yes or no, 1 or zero). |
Conditional Blocks | Code blocks that make comparisons - result in a true or false result (Boolean value). Found in Math blocks: Ex: 3 = 3 TRUE Ex: 2 > 10 FALSE |
IF ELSE Block | 2 way branching. 1 branch is for if the condition is true and the other is for if it is false |
If - Else if - Else ladder | App inventor checks the 1st if Statement and then the else ifStatement if it has to. Finally it will Check the Else statement if The other two are not true! |
Compound Conditions - AND & OR | Used to check if two or more conditions have been met Example: To get to level 2 the user must kill the boss AND have 100 gold |
Counted Repetition (For Statement) | Used to repeat blocks of code N amount of times. |
Conditional Loop | A conditional loop is used when we don't know in advance how often a process will have to be repeated. |
List | A collection of related data (i.e. high scores) stored to a variable. |
List index | The position of an element in a list The first spot is index 1, the second spot is index 2, etc. |