> For the complete documentation index, see [llms.txt](https://android-course.cornellappdev.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://android-course.cornellappdev.com/archive/archived-native-android-textbook-pages/5.-listviews/5.2-listview-performance.md).

# 3.2 ListView Performance

### Performance with ListView

With a list view, as a cell is “pushed” off the screen due to scrolling, that cell or `View` object is moved into a `Recycler` (not to be confused with `RecyclerView`) and the same `View` object is **reused** by the system.

![Diagram of how cells are recycled](https://i.stack.imgur.com/VLG9g.jpg)

If we look at the diagram above, when `Item 1` is pushed offscreen, it is saved in the `Recycler` and the `View` object is reused for `Item 8`. This can lead to all sorts of bugs. 

Let’s say, for example, that every item had a checkbox. If the checkbox in `Item 1` is checked, when the `Item 1`'s cell is reused, we’ll see that `Item 8` is created with the checkbox already checked. The text in `Item 8` has changed, but the `View` object itself has been reused. This is because the `View` objects in a list view are not attached to a certain position or item in the list.


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