 |
Author |
Topic: ordered layers and stacks (Read 257 times) |
|
kevinP
|
ordered layers and stacks
« on: May 25th, 2004, 11:22am » |
|
Hi all,
I was working on a little thing where one has to stack objects in a particular order; to do this I need to bring the selected object to the top. I used java.util.Stack and this worked fine (console demo code below) but I'm wondering if this is the best way to do this. Also when I draw my objects I'm iterating over the stack something like this:
Code:
// myDots is the Stack
for(int i=0; i<myDots.size(); i++) {
((Dot) myDots.get(i)).draw();
}
// for some reason the Iterator didn't work here
|
|
The Vector class (from which Stack is extended) has a "toArray" method; I thought that maybe it would be faster (for drawing) when I need all elements to first dump them en masse to an array and then iterate in the usual way over the array.
-K
Code:
// stack test - offers a nice little console demo of how Stack works
// stack extends Vector; (stores objects)
Stack myStack;
AnObject myObject;
int nbrElements;
void
setup()
{
myStack = new Stack();
for(int i=0; i < 6; i++) {
myStack.push(new AnObject(i));
}
nbrElements = myStack.size();
println("Stack contains " + nbrElements + " elements");
for(int i=0; i < 2; i++) {
AnObject tmp = (AnObject) myStack.pop();
println(" Popping top element (index #" + myStack.size() + ", value = " + tmp.value + ")");
}
nbrElements = myStack.size();
println("Stack now contains " + nbrElements + " elements");
println();
AnObject objectA = (AnObject) myStack.remove(2);
print("Removing element at index #2 (value = " + objectA.value + "). "); // prints "10"
println("Stack now contains " + myStack.size() + " elements");
AnObject objectB = (AnObject) myStack.remove(2);
print("Again removing element at index #2 (value = " + objectB.value + ". "); // prints "11"
println("Remaining stack now contains " + myStack.size() + " elements");
println();
myStack.push(objectB);
print("Pushing 2nd object from index #2 back onto stack. ");
println("Stack now contains " + myStack.size() + " elements");
Iterator it = myStack.iterator();
println("Iterating over stack");
while(it.hasNext()) {
AnObject tmp = (AnObject) it.next();
println(" Element with value: " + tmp.value);
}
int val = ((AnObject) myStack.get(1)).value;
println("Getting element at index #1 (value = " + val + ")");
println("Stack now contains " + myStack.size() + " elements");
AnObject objectC = (AnObject) myStack.pop();
println("Popping last element off stack; value = " + objectC.value);
}
class AnObject
{
int value;
AnObject(int myValue)
{
value = myValue;
}
void printValue()
{
println(value);
}
}
|
|
|
| « Last Edit: May 25th, 2004, 11:23am by kevinP » |
|
Kevin Pfeiffer
|
|
|
|
