#Greenfoot random code

#Greenfoot random code

That makes the code much cleaner and easier to understand. So this process of making a new method instead of just adding to act lets us move the code for the new method out of the act method, and just get a call from inside the act method. Just defining a method doesn’t get it executed. You might be the person trying to figure out your own code years after you wrote it, so make sure to comment properly! Compilers skip right over comments, only humans read them.Īfter we have defined the method, the code doesn’t get executed right away. That is very important as good code is used for a long time, and might have to be changed or maintained as circumstances change. Comments are to make it easier for people who read your code over later to understand how it works and what each section is supposed to do. If you have an error, then comment out a section and the error disappears, the error is in that section of code that you commented out. The comment is ignored by the computer, that’s why you can use implementation comments to check out a section of your code. The first four lines are a comment, (specifically a documentation comment). How about wormHunt? Let’s make a new method with the code below. The first step is to come up with a logical and easy to understand name for the new method. Try this 3.11 Let’s make a method for looking for a worm and eating it instead of writing that code in to the act method. To avoid this, we can chop it up in to smaller pieces. But if we keep doing this, we are going to have an act method that is too big and complicated to understand easily. So far we have been adding new behavior to the crab, eating worms, random turns, and dealing with the edge of the world.

That’s why you need to put the name of the class the method is in, then a dot, then the name of the method we want to use and it’s parameters (if any). Dot notation means the method is not in the class we are using right now, but is in the class Greenfoot. Greenfoot.getRandomNumber(20) is different from the other methods we called before, it uses the dot notation.

Means that you want Greenfoot to pick a random number for you between 0 and 19. With greenfoot the highest number possible is actually one number less than the limit and the lowest number possible is zero. When you tell someone to pick a number between 1 and 10, you are setting the limit to 10 (they will probably pick 7 by the way). The method getRandomNumber has to have a parameter that tells it how high the number can go (the limit of the number). Greenfoot can come up with a random number for us with getRandomNumber. One way to do that with Greenfoot is by using random numbers. The crab should actually go more or less in a straight line, but every now and then it should turn off course a little bit. While it walks, it goes in a straight line. Right now, the crab can walk across the screen and then turn when it hits the edge.