Thread: Chess Program

I'm talking about the displayed board and the position of pieces on it as controlled by the FEN-notation.
Not about how the program stores that data internally.

Yes the FEN-notation controls the position of the pieces if the FEN-notation is changed( press enter) the pieces on the board move to that postition
the first character in the FEN-notation the lower case 'r' is also the left upper corner of the earlier gridlayout(board) we build

What is the problem now using a FEN-notation String that shows where the pieces go row by row to position all the pieces on the board?

I have not started yet, but i dont know what i need classes, methods, techniques

Start by describing what the code needs to do. When that is decided, then worry about the code that is needed to do it.

Screen Shot 2013-08-10 at 1.37.31 PM.jpg

I need an FEN-Notation which represent the chesspieces and the squares(locations) on the board. If a user enters his own FEN notation like this one
rnbqkbnr/pp1pppppp/2p5/8/8/8/8/PPPPPPPP/RNBQKBNR the chesspiece Image moves to that position.

the / does nothing but between two / / there are 8 squares. and if a row is empty it shows 8

What will the code do that reads the String with the FEN-notation?
The FEN-notation string shows what is on all 64 squares of the board.
Some are empty, some have pieces on them.

When the code extracts a character from the String representing a piece, it will know what row and column that piece goes on

The FEN-notation string shows what is on all 64 squares of the board.
Some are empty, some have pieces on them

precisely!

The only thing the fen notation does when you change it is (fill in a notation and press enter) place the pieces on the right location/square

I'm confused what your problem is. Can you explain?
What more do you need to do besides read the FEN-notation string and use it to put pieces on the board?

nothing but my problem is "how" do i make that! Maybe Class FEN and what kind of methods how to make the string and put the pieces on the board

do i have to assign a letter to an piece object(image)..

How are pieces to be shown on the board? How will a Square know what piece is on it and how will it show that piece?
The FEN_notation string gives the piece and its location.
The chessboard will need a way to put a piece on a square.

How will a Square know what piece is on it

maybe a field and method isEmpyt(). how do i make the FEN class

how do i make the FEN class

What is that class for? What data will it hold? What methods will it have?

that are my questions:p dont know? somewhere the FEN-notation has to be checked if the notation is correct and when its correct the pieces must be placed on the right location

That sounds like what a method does: read the string and position the pieces.

any idea how i can build that?

What is the method supposed to do? Describe in detail.
Define all the steps the method needs to do first before writing any code.
Make a list of the steps it should do.

Woverine89 used to be gokuball

See post#36

- It has to read the FEN-notation
- Check the FEN-notation (is it a correct FEN notation Length and legal characters otherwise exception e, if a "row" is empty it shows 8) but thats is diffibult i dont work with rows right only the location shows the row number
- press enter
- The piece objects need to be placed on the right location.

Check the FEN-notation (is it a correct FEN notation Length and legal characters

That is the important bit. Expand that to the simple steps that need to be done.
There will be a loop.
The logic needs to get the next character from the String.

What tests need to be made? For example: Allow only one King and a max of 8 pawns.

exact, thats what the exercise describes! that kind of conditions.

how do i do that? Check every next character?

Check every next character?

Of course, you need to look at every character of the FEN-notation string.

do i have to put the string in an array? and the how do i set the 8 slashes / so they never change? they are always there