I have two separate objects ArrayList<String>
in two separate packages Top and top10. I assign the value of top10 to Top in my activity. And now if I remove an element from Top it also gets removed from top10. I don't know why is this happening? I feel totally dumbfounded. Is there something I don't know about java? Or is it android?
This is my activity code:
ArrayList<String> Top = new ArrayList<String>();
// ServiceCall is the name of the class where top10 is initialized.
Top = ServiceCall.top10;
System.out.println("top WR: "+ServiceCall.top10);
if(Top.get(0).equals("Please Select")) Top.remove(0);
System.out.println("top WR: "+ServiceCall.top10);
The second printed out statement has one element less than the one before.
You are pointing to the same Object.
Top = ServiceCall.top10;
is not creating a new Object, but making a reference to the other one, hence all changes in both pointers will be reflected in the same Object.
You'll have to create a new one passing the other one as parameter:
List<String> Top = new ArrayList<String>(ServiceCall.top10);
You are pointing Top to top10, not creating a new list (your initializer is effectively unused right now, as you are just repointing it to the other list.)
You should do:
ArrayList<String> Top = new ArrayList<String>(ServiceCall.top10);
This will create a shallow copy.
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