I'm pretty new to Java, and I'm trying to program an app that displays a list of points on a map. I've got that much working, now I want to work out the boundaries of the places to set the zoom area. To do this I have created a class that contains all my place objects, extending ArrayList() as below:
public class PlaceList extends ArrayList<Place> {
private static final long serialVersionUID = 4374092139857L;
public PlaceList() {
}
public Double getNorthernLimit() {
double mostNorthern;
for (Place curPlace: ???????) {
//check each place and keep most northern one
}
return mostNorthern;
}
My problem is that I don't know how to access the Arraylist of objects (where the ??? is). I want to loop through them out to determine the most northerly point.
Any help would be appreciated.
Just use this
:
for (Place curPlace : this)
{
}
I would personally avoid extending ArrayList<Place>
to start with though - I prefer to use composition over inheritance, so I would normally make my class contain a List<Place>
instead.
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