Question

I have one ListView, it contains check boxes. By default all check boxes are checked, if we uncheck any check box the position will be added to mCheckedArrayList. Now I want remove all unchecked positions from the Listview. I used the following code:

for(int i=0;i<=mCheckedArrayList.size;i++){
    int removePosition=mCheckedArrayList.get(i);
    mDisplayArrayList.remove(removePosition);
}

But it is giving an ArrayIndexOutOfBounds exception.

Answer 1

You are removing objects in the wrong order. You should always reverse the order of the loop if you are removing elements within the loop:

for(int i = mCheckedArrayList.size()-1 ; i >= 0; i--){
    mDisplayArrayList.remove(mCheckedArrayList.get(i));
}

As a side note, if you wanted to loop through front first (in cases where you are not deleting elements), you would have to change your loop end condition to the following:

i < mCheckedArrayList.size()

Thanks to Martín for the comment. To be aware of modifications you could always use a ‘final ref’ of the array.

final ArrayList<T> arrayListToBeUsed = mCheckedArrayList;
for(int i = arrayListToBeUsed .size()-1 ; i >= 0; i--){
    arrayListToBeUsed .remove(arrayListToBeUsed .get(i));
}