However, a black key should not be created when an empty string is encountered in the loop within the 'displayKeys' method. Adding blanks in the toggledBlack array will help to even out the arrays. In the Greenfoot IDE, which of the following are components of a parameter Mark for Review (1) Points (Choose all correct answers) Parameter type () Parameter. With the blank spaces in the arrays you are creating keys with the keyName not being equal to an existing key in Greenfoot.The blanks (empty strings) are place holders for where there is no black key on the piano keyboard. In the Key class you can't ckeck to see if a key is down if that key ('') doesn't exist.

Just like you didn't for all the other keys on the board.Įven if you do add in spaces into the array, you will still get errors, just in a different class. It happens to be that on a computer keyboard, the letter 'R' lies between the letters 'E' and 'T', but that doesn't mean you have to give it a blank index in an array. Instead of adding blanks into the toggledBlack array, the blanks in the other arrays should be removed. Yehuda wrote.I'm not sure what the purpose of all the blank array parts are for.

In my computer science class at school, Greenfoot throws weird exceptions that have nothing to do with my code but I am not sure if that is the case this time. The thing is that I am probably missing something, because no mater where I put it, it stops the game immediately and not when the Lobster eats the Crab. I triple checked and I am 99% sure that I did nothing wrong. I want to stop the game after the Crab eats the Worm, and for that in the Greenfoot manual I found the Greenfoot.stop () method. Key key = new Key(blackKeys, blackNotes + '.wav', 'black', toggledBlack) Key key = new Key(whiteKeys, whiteNotes + '.wav', 'white', toggledWhite) ĪddObject (key, 54 + (i*key.getImage().getWidth()), 140) Public Key(String keyName, String soundFile, String keyType, String toggle) Import greenfoot.* // (World, Actor, GreenfootImage, and Greenfoot) In Alice, you examine code where a bird moves its wings forward and backward while moving forward s Do not make any changes to the code. Greenfoot is an integrated development environment using Java or Stride designed primarily for educational purposes at the high school and undergraduate.

Greenfoot ide components