Thread: Changing the attribute of an instance object of a class that's declared in another package and whose variable is constructed by its parent class

Originally Posted by Norm

The posted method returns true or false on the first elements it looks at. Shouldn't it look at all the elements before making the decision for one of the values to be returned? The other value could be returned at the first failure.



I don't know the definition of a piece
or what a previous piece is
or what saving a piece means.


If legalDown() is a method in the Piece class (or the class it extends)
and shape is a variable in the Piece class (or the class it extends)
then that is how you could call the legalDown() method.


Can you explain what the method: legalDown() is supposed to do?
What are its args?
When does it return true or false?

public class collisiontest
{
 
	public static boolean legalDown(int currentX, int currentY, int[][] board, int[][] shape)
	{
	   int x = currentX+1;
	   int y = currentY;
 
	   for (int row = 0; row < 4; row++)
	   {
	   	for(int col = 0; col < 4; col++)
	   	{
 
 
	   		if (shape[row][col] == 1 && board[x+row][y+col] == 0)
	   		{
 
 
	   		}
	   		else
	   		{
	   			if (shape[row][col] == 0 && board[x+row][y+col] == 1)
	   			{
 
	   			}
	   			else
	   			{
 
	   			    if(shape[row][col] ==0 && board[x+row][y+row] == 0)
	   			    {
 
	   			    }
 
	   			    else
	   			    {
 
	   				return false;
	   			    }
	   			}
	   		}
	   	}
	   }
 
 
    return true;
	}
 
 
public static void main(String[] args)
{
  		int [][] m1 =
		{{1,1,0,0},
		 {1,1,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		};
 
 
		int[][] board =
		{{0,0,0,0},
		 {0,0,1,1},
		 {0,0,1,1},
		 {0,0,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		};
 
			int[][] board3 =
		{{0,0,0,0},
		 {0,0,1,1},
		 {0,0,1,1},
		 {1,0,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		};
 
		int[][] board2 =
		{{0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {1,1,0,0},
		};
 
int currentX = 1;
int currentY = 0;
 
		System.out.println(legalDown(currentX, currentY, board, m1));
 
		System.out.println(legalDown(currentX, currentY, board3, m1));
 
		System.out.println(legalDown(currentX, currentY, board2, m1));
 
 
 
 
 
 
 
 
 
 
}
}

it's working now.

previous pieces = the pieces that fell onto another piece or the floor

legaldown is supposed to return true if we can move down and return false if we can't

it will be used inside moveDown

Now, I need to know where Board (int array representing all the pieces that were laid down) is located.

To fill in the board square covered by a piece, it would be helpful to have a method similar to the one above that copies the non-zero entries from the given array into the corresponding board squares.

I need to implement this now, but I have the following questions:

where do I put the contents array? I don't see a board array in the program

do i need to put the contents array inside the board once it was laid down or once it appears? and how do i know a piece was laid down? what if statement should i use for that?

Originally Posted by Norm

Did you look at the Board class? It has a contents array in the class it extends.


I have no ideas about how the variables in the classes should be changed or used as the game is played. I don't know the game.

how do i access the board though? I don't see any 2d array i can reference to...

Tetris Battle - 145 lines - T-spin - Rank 50 - YouTube

this video should help you understand what's tetris.

--- Update ---

Originally Posted by Norm

Did you look at the Board class? It has a contents array in the class it extends.


I have no ideas about how the variables in the classes should be changed or used as the game is played. I don't know the game.

Yeah there is a content array: int[][] contents

but I use int[][] contents to rotate the pieces.

So if I understand, when I callled currentPiece.moveDown(), it modified the int [][] contents attribute that belonged to the Piece class? So, if I want to modify the int [][] contents attribute of Board, I have assign the int [][] contents attribute another array inside board.method()? I can't modify contents inside a method if I don't specify the instantiated class object like this: board.method() or currentPiece.method(), right?

--- Update ---

Ok, I think I might be able to do this...

To fill in the board square covered by a piece, it would be helpful to have a method similar to the one above that copies the non-zero entries from the given array into the corresponding board squares.

So, basically, I have to write a method I call below updatePosition() in moveLeft;

synchronized void moveLeft() {

currentX--;
updateLocation();
method();

}

that method is in Board

Now, since I call method() from the class Piece

I can't just write

contents = int[][]a, right?

Do I have to write:

Board.contents = int[][] a?

I am not sure about this...

I think I will be able to modify it, but I have to know how to access contents.

Earlier I could just write

contents = a; // a = int[][]array

but that was because the method call was: currentPiece.moveDown()

Originally Posted by Norm

Those would be how a method for each of those classes would be called.


A method in the Board class can access variables defined in the class.


These problems are very basic OOP programming. If you are having problems understanding what is going on I suggest that you work with some very simple classes that extend others and test using methods that update variables in the classes.

Ok, thanks. So, this is what I must do, right?

synchronized void moveLeft() {

currentX--;
updateLocation();
board.method();

}

Originally Posted by Norm

Sorry, I don't know what you are trying to do in that method
and what class that method is in
and I don't know what those methods do.

sorry.

method = addArray

method is inside Board

 
public class addarray
{
 
	public static void addArray(int currentX, int currentY, int[][] board, int[][] shape)
	{
	   int x = currentX;
	   int y = currentY;
 
	   for (int row = 0; row < 4; row++)
	   {
	   	for(int col = 0; col < 4; col++)
	   	{
 
 
	   		if (shape[row][col] == 1 )
	   		{
 
				board[x+row][y+col] = 1;
	   		}
 
 
	   	}
	   }
	}
 
 
 
	public static void printArray(int [][] array)
	{
		for(int row = 0; row < array.length; row++)
		{
			for(int col = 0; col < array[row].length; col++)
			{
				if (array[row][col] > 0)
				{
 
				System.out.printf("1");
				}
				else
				System.out.printf("0");
			}
			System.out.printf("\n");
		}
 
	}
 
 
 
 
public static void main(String[] args)
{
  		int [][] m1 =
		{{1,1,0,0},
		 {1,1,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		};
 
 
		int[][] board =
		{{0,0,0,0},
		 {0,0,1,1},
		 {0,0,1,1},
		 {0,0,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		};
 
			int[][] board3 =
		{{0,0,0,0},
		 {0,0,1,1},
		 {0,0,1,1},
		 {1,0,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		};
 
		int[][] board2 =
		{{0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {0,0,0,0},
		 {1,1,0,0},
		};
 
int currentX = 1;
int currentY = 0;
 
addArray(currentX, currentY, board, m1);
 
printArray(board);
 
 
 
 
 
 
 
 
 
 
 
}
}

I still don't understand how come we write contents instead of shapes (Piece class)or contents instead of int[][] (Board class). It seems counterintuitive, but it kinda make sense since the only way to modify their attributes (for Board and Piece instance objects) is by writing currentPiece.method() or board.method().

When should I call removeRows and fallRows

// traverse the array, remove rows, save index
// traverse arrays and put 1 below x number of rows using index and remove the 1 above it
//
public class removerows
{
 
	public static void printArray(int [][] array)
	{
		for(int row = 0; row < array.length; row++)
		{
			for(int col = 0; col < array[row].length; col++)
			{
				if (array[row][col] > 0)
				{
 
				System.out.printf("1");
				}
				else
				System.out.printf("0");
			}
			System.out.printf("\n");
		}
 
	}
 
 
 
 
	public static void removeRows(int [][] array)
	{
		for(int row = 0; row < array.length; row++)
		{
			int number = 0;
 
			for(int col = 0; col < array[row].length; col++)
			{
 
 
				if(array[row][col] == 1)
				{
					number++;
 
				}
 
 
				if(number == 4)
				{
 
				  for(int col2 = 0; col2 < array[row].length; col2++)
				  {
				  	array[row][col2] = 0;
 
				  }
 
				}
 
			}
 
		}
 
	}
 
	public static void rowFall(int [][] array)
	{
		int rowDistance = 0;
 
		for(int row = array.length-1; row >= 0; row--)
		{
			int number = 0;
 
 
 
 
			for(int col = 0; col < array[row].length; col++)
			{
				if(array[row][col] == 0)
				{
					number++;
 
				}
 
				if (number == 4)
				{
					rowDistance++;
 
				}
 
				if(array[row][col] == 1 && rowDistance > 0)
				{
					for(int col2 = 0; col2 < array[row].length; col2++)
					{
						array[row+rowDistance][col2] = array[row][col2];
 
						array[row][col2] = 0;
 
 
 
					}
 
					//recursion call
 
					rowFall(array);
 
 
 
				}
 
 
			}
		}
	}
 
 
public static void main(String[] args)
{
 
 
		int[][] board =
		{{0,0,0,0},
		 {0,0,1,1},
		 {1,1,1,1},
		 {0,0,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		 {1,1,1,1},
		};
 
	System.out.println("implementing removeRow");
	removeRows(board);
	printArray(board);
	rowFall(board);
	System.out.println("implementing rowFall");
	printArray(board);
 
 
 
 
}
 
}

	void dropPiece() {
		currentPiece = PieceFactory.createPiece();
		mainPanel.add(currentPiece);
		currentPiece.repaint();
		currentPiece.fall();
		//mainPanel.remove(currentPiece);
		board.repaint();
		addToScore(1);
	}

Here right?

Should it be like this?

	void dropPiece() {
		currentPiece = PieceFactory.createPiece();
		mainPanel.add(currentPiece);
		currentPiece.repaint();
		currentPiece.fall();
		//mainPanel.remove(currentPiece);
[B]                board.removeRows()
                board.rowFall()[/B]
		board.repaint();
		addToScore(1);
	}

And why was mainPanel.remove(currentPiece); commented out?

I think I will just test it.

--- Update ---

Should it be shape[row][col] or the other way around (shape[col][row])?

	void fall() {
 
		while(legalDown(currentX, currentY, board.contents, currentPiece.contents) && isNotOutOfBoundDown(currentX, currentY, board.contents, currentPiece.contents))
		{
		currentX--;
		updateLocation();
    	updateSize();
		}
 
		Tetris.sleep(2000);
	}

uhm what do I need to replace board.contents and currentPiece.contents with?

this fall method is inside the Piece class.

I get error: cannot find symbol

I kinda knew this problem would arise, but I can't think of a way to solve it.

--- Update ---

	static Board board;
	static Tetris game;
 
	JPanel mainPanel;
	public Piece currentPiece;
	int score = 0;
	JButton scoreButton;

This is in Tetris.java

the currentPiece is already public, but I can't access the variables.

the board is not public, I should make it public, but it won't change a thing probably.

error: cannot find symbol line 75 while(legalDown(currentX, currentY, board.contents, currentPiece.contents) && isNotOutOfBoundDown(currentX, currentY, board.contents, currentPiece.contents))

--- Update ---

board.contents, currentPiece.contents board.contents, currentPiece.contents

error: cannot find symbol
error: cannot find symbol
error: cannot find symbol
error: cannot find symbol

I get this 4 times I can only assume it's because of those variable names

Originally Posted by Norm

Which variable is not found? board, currentPiece or contents?

contents most probably

board = instance object of Board
currentPiece = instance object of Piece
contents = int[][] array inherited by Board and Piece.

I seriously don't know what to pass in as parameters.

Originally Posted by wholegrain

If that's the case, I find it weird that you couldn't help me the slightest bit and you kept asking those silly questions.

I'm seeing amazing and patient help from Norm, despite this ludicrous and insulting post that you've never corrected or commented on. Consider retracting it.

I am sorry. I didn't know he had no idea what Tetris was. I thought he was trolling me.