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How do you make a list that contains another list?
Hi! I am finding it hard to make a list that contains another list of ints, like this;
int[] xList = new int[500]; // Initialize xList int[] xListNr2 = new int[500]; //Another intList ?[] listOfLists = new ? [2]; // List made to contain several int[] for[...] // For-loop to declare xListsValue /* Since I don't know how to initialize "listOfLists" problems occure here */ listOfLists[0] = xList; listOfLists[1] = xListNr2;
I don't know what to put at the '?' marks, help?
Related threads:
Re: How do you make a list that contains another list?
Are you asking how to define a two dimensional array?int[][] twoD = new int[2][]; twoD[0] = new int[6]; // 6 elements for first one twoD[1] = new int[123]; // 123 elements for second one
If you don't understand my answer, don't ignore it, ask a question.
Re: How do you make a list that contains another list?
Nope. I am asking how to define a array/list (or whatever it is called) that contains other lists;Originally Posted by Norm
Re: How do you make a list that contains another list?
For an ArrayList read the API doc: Java Platform SE 7
An ArrayList can contain a list of any type of object.
Also see the tutorial:
http://docs.oracle.com/javase/tutori...aces/list.html
If you don't understand my answer, don't ignore it, ask a question.
Re: How do you make a list that contains another list?
I looked into that a bit, didn't help me much; in-fact, not at all.
Maybe explaining what I want to use it for will make things easier.
I have a loop with a 'drawLine' in it, and for anyone who doesn't know drawLine just draws a line between the two x- and the two y-values that you set.
In this loop i draw a line between every single point in the two lists (x- and y-list) and now I want to easily draw multiple lines (like, more than thousand).
An example for how the list(s) can look and how I want draw the line.
for(int i = 1; i<xList.length; i++){ xList[i] = i; yList[i] = (int) (1.1*xList[i]); } //....In paint(Graphics g)...// for(int i = 1; i<xList.length; i++){ g.drawLine(x + xList[i-1], y + yList[i-1], x + xList[i], y + yList[i]); }
Now instead of having to initate a thousand different x- and y-lists and then using g.drawLine for each different list I want to make some sort of list or array that can hold these different lists.
I wanted my words to turn into action,
so I become a programmer
Re: How do you make a list that contains another list?
If you don't want a 2 dimensional array or an arraylist, I have no idea what will solve your problem.
If you don't understand my answer, don't ignore it, ask a question.
Re: How do you make a list that contains another list?
I think I'll just go with making it into an object and making a list of object references.
Cheers!
I wanted my words to turn into action,
so I become a programmer
Re: How do you make a list that contains another list?
ArrayList<ArrayList<Integer>> listofLists=new ArrayList<ArrayList<Integer>>();
ArrayList<Integer> singleLists=new ArrayList<Integer>();
singleLists.add(1);
singleLists.add(2);
singleLists.add(3);
listofLists.add(singleLists);
--- Update ---
ArrayList<ArrayList<Integer>> listofLists=new ArrayList<ArrayList<Integer>>();
ArrayList<Integer> singleLists=new ArrayList<Integer>();
singleLists.add(1);
singleLists.add(2);
singleLists.add(3);
ArrayList<Integer> anotherlist=new ArrayList<Integer>();
anotherlist.add(5);
anotherlist.add(6);
anotherlist.add(7);
listofLists.add(singleLists);
listofLists.add(anotherlist);
for(ArrayList<Integer> i:listofLists)
System.out.println(i);
Re: How do you make a list that contains another list?
@india, I'm unclear of the purpose of your post. You have posted code with absolutely no explanation, which leads me to believe you are trying to help through spoonfeeding, in which case please read http://www.javaprogrammingforums.com...n-feeding.html
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