CODEWITHSUNDEEP
javaandroidlistviewandroid-listviewarraylist
Rachel
Rachel

Reputation: 505

Android adding and removing to a different ListView using ArrayList

This has been driving me insane. I have a ListView and a ArrayList as my adapter. The ListView mode is CHOICE_MODE_MULTIPLE and the layout is simple_list_item_checked. I can now select multiple items in my ListView.

My situation:

    int length = jsonList.size();

    SparseBooleanArray checked = lv_Devices.getCheckedItemPositions();

    for (int i = 0; i <length ; i++ ){

         if (checked.get(i)) {


             onList.add(jsonList.get(i));

             jsonList.remove(i);
             lv_Devices.setItemChecked(i, false);


             length--;

        }   
    }
    adapter.notifyDataSetChanged();
    adapterOn.notifyDataSetChanged();

Here is the LogCat: 

size of array 8 : contains [1, 2, 3, 4, 5, 6, 7, 8]  

you removed index 0  
[2, 3, 4, 5, 6, 7, 8]  


you removed index 1  
[2, 4, 5, 6, 7, 8]  


you removed index 2  
[2, 4, 6, 7, 8]  


you removed index 3  
[2, 4, 6, 8]

As you can see from the end result the array is shifting indexes. The goal I am trying to achieve: get each selected item and add them to the other ListView while removing from the current ListView.

The LogCat shows what happens when I select all the items. This is also happening on a button click. Any advice on this would be perfect. This is also my first time using stackoverflow. I don't really use it much as the majority of programming errors have been discussed on here. I am having difficulty on this subject.

Upvotes: 1

Views: 122

Answers (1)

user184994
user184994

Reputation: 18281

Try something like this:

int item = 0;

for (int i = 0; i < length; i++) {

    if (checked.get(i)) {
        onList.add(jsonList.get(item));
        jsonList.remove(item);
        lv_Devices.setItemChecked(i, false);
    }
    else {
        item++;
    }
}

It will try to remove the first item in the array (item 0). If that item is checked, it will be removed. This means the item that was previously item 1 is now item 0, so it will just check item 0 again.

If, however, item 0 is not checked, it will move on to item 1, and keep doing the same thing.

Upvotes: 1

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