NSMutableArray removeObjectAtIndex

Question

If I have an NSMutableArray with 10 objects

I run this line of code

[tempArray removeObjectAtIndex:0];

then

[tempArray count] should return 9

but does the entire Array shift up

Object At Index 1 moves to Index 0
Object at Index 2 moves to Index 1
...
Object at Index 9 moves to Index 8

or is Index 0 = nil?

Dirk · Accepted Answer · 2011-05-03 20:14:57Z

7

To fill the gap, all elements beyond index are moved by subtracting 1 from their index.

answered May 3, 2011 at 20:14

Dirk

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1 Comment

right but is this done by iOS or do we have to manually make a method to do this? (Sorry for the dumb question).

Joe · Accepted Answer · 2011-05-03 20:14:41Z

2

The array will shift all of the objects down 1 from the right of the removed index. Index 0 will be what was at index 1 and so forth.

answered May 3, 2011 at 20:14

Joe

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Jakub Truhlář · Accepted Answer · 2015-11-29 18:40:02Z

0

removeObjectAtIndex shifts indexes down

insertObjectAtIndex shifts indexed up

addObject adds object at the end so there is no shifting

answered Nov 29, 2015 at 18:40

Jakub Truhlář

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