Android Question index out of bounds

[coder19075]

I'm getting a bug on just trying to increment an integer.

The error is: java.lang.IndexOutOfBoundsException: Invalid index 2, size is 2

Here is the code to reproduce:

Dim lst As List
lst.Initialize
Dim obj1 As Map
obj1.Initialize
obj1.Put("id", 888)
Dim obj2 As Map
obj2.Initialize
obj2.Put("id", 999)
Dim obj3 As Map
obj3.Initialize
obj3.Put("id", 999)
lst.Add(obj1)
lst.Add(obj2)
lst.Add(obj3)

Dim lst2 As List
lst2.Initialize

For Each p As Map In lst
    Dim i As Int = 0
    For Each p2 As Map In lst
        If p.Get("id") = p2.Get("id") Then
            lst.RemoveAt(i)
        End If
        i = i + 1 'error in this line
    Next
    lst2.Add(p)
Next

 

[Erel]

Moved to the questions forum. It is not a bug.

You shouldn't modify the list from inside a For Each block that iterates over the list items.

What are you trying to implement?

 

[An Schi]

Had this confusing me as well

When you want to have index 2 the size should be 3 (index 0, index 1 and index 2).

 

[coder19075]

"You shouldn't modify the list from inside a For Each block that iterates over the list items."

Why?

I'm trying to remove duplicates from a list.

 

[eurojam]

try this:

Dim obj1 As Map
obj1.Initialize
obj1.put(888,"")
obj1.put(999,"")
obj1.put(999,"")

Dim lst As List
lst.Initialize
For Each k As Int In obj1.Keys
    lst.add(k)
Next
Log(lst)

 

[eps]

"You shouldn't modify the list from inside a For Each block that iterates over the list items."

Why?

I'm trying to remove duplicates from a list.

Think about it.

The For Loop thinks that it's dealing with 4 items... You remove 2 inside the loop and it will hit the end of the loop before it expects to and then give an Out of Bounds Exception.

Ideally only move non-duplicates to a new list.

 

[eps]

Maybe use this? https://www.b4x.com/android/forum/t...odness-some-useful-methods.58963/#post-371220

 

[coder19075]

Thanks, that was helpful