Why Does My Android ListView's getView() Method Get Called Multiple Times and in an Apparently Random Order?

Why is getView Being Called Multiple Times and in No Coherent Order?

As you've observed in your custom list adapter, the getView method is called numerous times for each row, and it's seemingly done in a haphazard manner. This behavior can be confusing, but it's actually not an issue in Android's design.

Why Multiple Calls?

Despite common belief that getView should only be called for visible rows, that's not the case. ListView items are recycled and reused as you scroll through the list. To facilitate this recycling, ListView pre-measures and caches views for rows that are about to become visible. This pre-measurement process requires multiple calls to getView to determine the dimensions of the view.

The "No Coherent Order"

The perceived lack of order in getView calls is also a side effect of recycling. As rows are scrolled out of view, their associated views are removed from the cache and reused for views that are about to become visible. This means the order of getView calls can vary depending on the user's scrolling behavior.

Your Specific Example

In your case, you've provided the ListView a wrap_content height. This forces ListView to measure several children at layout time to determine its own height. Consequently, ListView creates cache views for those children before you even begin scrolling.

Conclusion

ListView's recycling mechanism is essential for maintaining smooth scrolling performance. While the order and number of getView calls may seem erratic, it's a natural byproduct of this mechanism and is not an error or bug.

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