Why Does My Custom ListView Adapter's `getView` Method Get Called Multiple Times?

Custom ListView Adapter 'getView' Method Invocations

In a custom ListView adapter, the 'getView' method can indeed be invoked multiple times in seemingly random order. This behavior is attributed to how ListView initializes its layout.

When a ListView is initially populated with data, it estimates its size based on a few children it measures from the adapter. This is done to optimize scrolling performance. In your case, the ListView has wrap_content height assigned. As a result, it measures a subset of your children to determine its preferred height.

This measurement process leads to the 'getView' method being called multiple times even before any user interaction. As list items are reused, convertViews are passed to 'getView' to enhance performance. However, the order in which 'getView' is called and the number of times it's invoked are not guaranteed.

Reasons for Multiple 'getView' Calls

• Pre-Layout Initialization: ListView needs to determine its height and hence measures a few children.
• Variable View Visibility: The position values you observe could be due to the fact that ListView recycles views and measures additional children to account for potential scrolling.
• Data Modification: If the data associated with the ListView changes, getView() may be called to reflect the updates.

Tips for Efficient 'getView' Implementation

• Avoid doing expensive operations in 'getView' as it can slow down ListView scrolling.
• Consider using ViewHolder pattern to improve performance by caching view components.
• Ensure that your adapter notifies the ListView of data changes to prevent unnecessary getView() calls.

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