Display-Array-Java

Code to graphically display the contents of a square array of ints.

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Preamble: This program originated from a desire to make more use of 2D arrays in teaching Java programming. I thought that it would be really handy if there was a prebuit program that would handle the graphics of displaying a 2D array. Seeing a graphical representation of an array makes it more understandable, and should motivate students to experiment more. It's not really that hard to do the graphics, but it takes a couple of weeks to teach, and often there is only time for that later on in the course (if at all).

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Features:

• Integer values of 0-15 are coloured in different colours. It would be nice also to be able to colour in a value of x=-1, but I haven't gotten around to that yet.
• Integer values of 48-90 are displayed as the ASCII character. This allows the user to display capital letters, digits 0-9, and some punctuation.
• The array size can be set to anything from 1x1 to 80x80
• The array can be resized by dragging it once it's displayed
• The title can be set to whatever you want
• Grid lines can be enabled or disabled
• Mouse clicks send the coordinates of the mouse click back to the main program
• A timer can be set so that a program can be run without requiring mouse clicking (e.g. the game of Life).

Requirements:

• For simplicity's sake, the array must be a square array of integers (int).
• The main user class can be called anything - however, we must have a way to send data back and forth between the user program and this program (called DisplayArray.java).

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Versions

• There are three versions with very similar functionality, but with one significant difference.
• Each version is in a different branch of this repository.

1️⃣ The master branch has the version where all of the control is surrendered to DisplayArray.java

• This is done to IDIOT PROOF the program.
• How it works:
  1. the user program creates its own array and initializes it
  2. the user program creates a DisplayArray object and passes its own instance to it
  3. the display array program then interrogates the user program via method calls to get the data needed in the correct sequence for the program to work correctly.
• How does the DisplayArray program connect with the user program?
  1. The user program must extend ArrayGame. This means that the DisplayArray program knows what type of object it is, regardless of the class name of the user program.
  2. ArrayGame implements an interface ArrayDataInterface. This forces the user program to include all of the methods listed so that DisplayArray can call them when it is appropriate to do so.
  • The limitation with this is that there is no way to change a colour (e.g. if you want 1=RED). You have to edit DisplayArray.java
• It is also a bit more awkward to think of (perhaps). You're just writing methods in the user program, rather than a complete working game.

2️⃣,3️⃣ For descriptions of the other versions, which allow more user control, please see the Readme file in the branches observer-pattern and lambda-pattern

There is a sample user program in each branch, called UserArrayGame.java that can be used as a starting template for making array programs to work with DisplayArray.java.

⚠️ Do not modify any other files (except perhaps to change the colours in DisplayArray.java).