Discussions

I am not really sure that synchronized needed to be used here in the Explosion class. When a method is declared to be synchronized, two or more different threads cannot simultaneously execute the method. One would be forced to wait until another has finished its execution of it. This is, however, most probably beyond the scope of what you should be concerned with at this point.

The images field is declared to hold an array of GreenfootImage objects. Line 6 creates an array of length IMAGE_COUNT and assigns it to the field. The for loop says to count up to that number of images (the count, held in 'i' will be used to point to a particular image in the array, as an index). When you see square brackets like that in any java code, then an array is being dealt with.

The final keyword is used to indicate that the value or object assignment is not allowed to change. The assigned value is a constant or the object is permanently assigned. If an attempt is made to make a re-assignment, a compilation error will ensue.

It take a vector (a direction and a magnitude, "length"), and converts it to the distances they make along the x and y axes to get to the same end-point.

The move method of the Actor class requires an int value in the parentheses. See here.

If you mean to change to bold or italicized, you can create a new Font with those characteristics. Without testing, I think you could change line 10 to something like: <Code Omitted>

This particular Counter class has an animated score display. If, let us say, 5 points was to be added to the score, the true score is set as a target for which the value of the counter (which is displayed) is to more slowly progress to. So, if the value of the counter was zero (as is the value of target), when 5 is added, target is set to 5 and the displayed value will be seen to be "rolling" up to the new "target" value. The act method basically says to change the shown value by one toward the target value if

The error is in the previous line (line 3). It just "runs" into the next line because the compiler is trying to make sense of line 3 (which is not a completed line of code). Why are you adding asteroids into the world in a method that is to create stars?

To determine the smallest delay (without having no delay), one would need to see how you are running the counter and when it is incremented with respect to when you check its value and reset its value during an act cycle.

get flamed bro!

A class can create multiple same-type object and each will have their own state. That is to say, which Cat instance are you trying to determine is tired? Cat, being the name of a class, does not answer this. You need to get the state of an object of the class, not the class itself.

Thank you so much!

In more recent versions of Greenfoot, we no longer use java.awt.Font and instead have our own greenfoot.Font class. Remove the line near the top that says "import java.awt.Font". Then change line 22 in the snippet to be new Font("Comic Sans MS", 32) without the Font.PLAIN part. That should get the code working.

Hi! The first rule of asking for help is "give details" :) Without knowing what you've tried and what happened when you did, no-one can help. The best I can say is that you can download Greenfoot from the "download" section of this website, and the installation instructions are linked from there as well.

Just move (cut and paste) lines 10 through 13 into an act method within the class.