Checkbox in ListView with odd checking behaviour

Question

I am new to Java and Andriod development.

I have a view within my app which contains a ListView

I then have a custom Adapter which inherits from an ArrayAdapter

within the view in the getView method I return a row which contains some text and a checkbox

now so far this all works great my list is populated and I can check my items, and all the events seem to fire as expected.

My problem that I am having is that I check the first 3 items and then I notice that the 11th, 12th and 13th items are checked and as I scroll I see that at regular intervals other checkboxes also seem to be checked in the same pattern.

If I check about 10 checkboxes then it will end up checking all the items in the list of about 80...

can anyone explain what I have done wrong?

I dont think any code will help explain this as I do not set the checkstate of the checkbox anywhere, this is all handled itself, so the fact items are being checked is puzzling me.

Thanks in advance

anything that is not clear please ask and I will respond to the best of my ability :D — Squirrel5853, Jul 16 '12 at 21:55
If you put the code of your getView method I can tell you exactly where happens the issue ;) — Litus, Jul 16 '12 at 22:08

score 3 · Accepted Answer · edited May 23 '17 at 12:27

3

This is happening because Android recycles list items for performance purposes, here you have the solution of this problem: ListView reusing views when ... I don't want it to

Hope to help :)

edited May 23 '17 at 12:27

Community

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answered Jul 16 '12 at 22:08

Litus

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thanks very much will check it out and then mark as appropriate :) – Squirrel5853 Jul 16 '12 at 22:12

score 1 · Answer 2 · answered Jul 16 '12 at 22:11

This is expected behavior. ListView reuses views in the adapter. So what you want is to keep a Set of "selected items" and add an item or remove it when the CheckBox is clicked and then in your getView add the following code:

if(mSelected.contains(getItem(position)) {
    checkBox.setChecked(true);
} else {
    checkBox.setChecked(false);
}

This way when the row is reused the CheckBox will be the proper status.

Checkbox in ListView with odd checking behaviour

2 Answers2