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PowerDj
PowerDj wrote ...

2020/1/4

Getting world to use class methods

PowerDj PowerDj

2020/1/4

#
In the game I'm programming, I need the world to be able to instantiate a "block". In the Block class, I already have a method, called generateBlock(), which generates a block. Ideally, I want the world to use something like "Block.generateBlock()" to instantiate a block, but because generateBlock() uses static methods, I cannot do this. Is there any way I can get around this, and tell the world to use a static method from the Block class?
danpost danpost

2020/1/4

#
PowerDj wrote...
In the Block class, I already have a method, called generateBlock(), which generates a block
Please show generateBlock method coding.
PowerDj PowerDj

2020/1/4

# 
    public void generateBlock() {
        //randomly generate a colour (out of 4 possible) and shape (out
        //of 9 possible) for the next block
        String blockColour = Integer.toString(Greenfoot.getRandomNumber(4));
        String blockShape = Integer.toString(Greenfoot.getRandomNumber(2));

        //instantiate a new image
        GreenfootImage blockImage;
        //assign an image based on the randomly generated numbers
        //images names use 'colour_shape' to make them all the same
        blockImage = new GreenfootImage(blockColour + "_" + blockShape + ".png");

        //finally, instantiate a new block and give it the generated image
        setImage(blockImage);

        //the rotation of the block must be set back to normal before placing it
        //since it retains the rotation of when it was placed otherwise
        setRotation(0);

        //each block shape has a different centre point
        //therefore they need to be placed in slightly different places
        //to ensure that they are put onto the grid
        if(blockShape.equals("0")){
            setLocation(432,382);
        }else if(blockShape.equals("1") || blockShape.equals("2") || blockShape.equals("3") || blockShape.equals("4")){
            setLocation(445,382);
        }else if(blockShape.equals("5") || blockShape.equals("6")){
            setLocation(432,368);
        }else if(blockShape.equals("7") || blockShape.equals("8")) {
            setLocation(445,368);
        }
    }
danpost danpost

2020/1/4

#
PowerDj wrote...
<< Code Omitted >>
Okay -- now I need to see all code-blocks in your World subclass dealing with the Block objects (including your attempt(s) to call the given method).
PowerDj PowerDj

2020/1/4

# 
    private void prepare()
    {
        leftEdge leftEdge = new leftEdge();
        addObject(leftEdge,204,382);
        upperEdge upperEdge = new upperEdge();
        addObject(upperEdge,460,179);
        rightEdge rightEdge = new rightEdge();
        addObject(rightEdge,717,382);
        lowerEdge lowerEdge = new lowerEdge();
        addObject(lowerEdge,460,586);
        Grid grid = new Grid();
        addObject(grid,459,382);
        generateBlock();
        setPaintOrder(Block.class, placedBlock.class);
    }
    public void generateBlock() {
        //randomly generate a colour (out of 4 possible) and shape (out
        //of 9 possible) for the next block
        blockColour = Integer.toString(Greenfoot.getRandomNumber(4));
        blockShape = Integer.toString(Greenfoot.getRandomNumber(9));
        
        //instantiate a new image
        GreenfootImage blockImage;
        //assign an image based on the randomly generated numbers
        //images names use 'colour_shape' to make them all the same
        blockImage = new GreenfootImage(blockColour + "_" + blockShape + ".png");
        
        //finally, instantiate a new block and give it the generated image
        Block block = new Block();
        block.setImage(blockImage);
        
        //each block shape has a different centre point
        //therefore they need to be placed in slightly different places
        //to ensure that they are put onto the grid
        if(blockShape.equals("0")){
            addObject(block,432,382);
        }else if(blockShape.equals("1") || blockShape.equals("2") || blockShape.equals("3") || blockShape.equals("4")){
            addObject(block,445,382);
        }else if(blockShape.equals("5") || blockShape.equals("6")){
            addObject(block,432,368);
        }else if(blockShape.equals("7") || blockShape.equals("8")) {
            addObject(block,445,368);
        }
    }
At the moment the world has its own generateBlock() method identical to the other one but this isn't ideal for what I want to do. 
    public void generateBlock() {
        Block block = new Block();

        block.generateBlock();
    }
I tried this, which compiles but doesn't generate a block. 
    public void generateBlock() {
        Block.generateBlock();
    }
I also tried this, which doesn't compile because generateBlock() isn't static.
danpost danpost

2020/1/4

#
The "new Block", aka block, needs to be added into the world before you can call "block.generateBlock". You can add it at coordinates (0, 0).
PowerDj PowerDj

2020/1/4

#
Works perfectly, huge thanks!
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