## Description
When a List widget has a selected item and is hidden then unhidden
(unmounted/mounted), an infinite render loop occurs in the following
flow:
```typescript
// Triggered in componentDidUpdate
if (this.shouldUpdateSelectedItemAndView() && isString(this.props.selectedItemKey)) {
this.updateSelectedItemAndPageOnResetOrMount();
}
```
### Root Cause
This happens because:
1. `updateSelectedItemAndPageOnResetOrMount` calls `updatePageNumber`.
2. `updatePageNumber` uses `calculatePageNumberFromRowIndex`, which
depends on `this.pageSize`.
3. Each page number calculation triggers a meta property update through
`onPageChange`.
4. This meta update causes a rerender, repeating the cycle.
#### Problematic Calculation
`this.pageSize` is calculated dynamically based on widget dimensions:
```typescript
calculatePageNumberFromRowIndex = (index: number) => {
return Math.ceil((index + 1) / this.pageSize); // Using unstable this.pageSize
};
```
This creates instability during mount/unmount cycles as:
- Widget dimensions may not be fully stabilized.
- Each meta property update triggers recalculation.
- No break in the update-rerender cycle.
### Solution
Use `this.props.pageSize` instead of `this.pageSize` in page
calculations:
```typescript
calculatePageNumberFromRowIndex = (index: number) => {
return Math.ceil((index + 1) / this.props.pageSize); // Using stable props value
};
```
### Why This Works
- `this.props.pageSize` represents the last stable value set through the
meta property system.
- It's protected by the existing `pageSizeUpdated` flag mechanism.
- Breaking the dependency on dynamically calculated dimensions prevents
the infinite loop.
Fixes#37683
## Automation
/ok-to-test tags="@tag.Widget, @tag.Binding, @tag.List, @tag.Sanity"
### 🔍 Cypress test results
<!-- This is an auto-generated comment: Cypress test results -->
> [!TIP]
> 🟢🟢🟢 All cypress tests have passed! 🎉🎉🎉
> Workflow run:
<https://github.com/appsmithorg/appsmith/actions/runs/13366216706>
> Commit: 74028ec9f52aa25daf0d72c7cdf3c4fa9701e86e
> <a
href="https://internal.appsmith.com/app/cypress-dashboard/rundetails-65890b3c81d7400d08fa9ee5?branch=master&workflowId=13366216706&attempt=1"
target="_blank">Cypress dashboard</a>.
> Tags: `@tag.Widget, @tag.Binding, @tag.List, @tag.Sanity`
> Spec:
> <hr>Mon, 17 Feb 2025 10:23:19 UTC
<!-- end of auto-generated comment: Cypress test results -->
## Communication
Should the DevRel and Marketing teams inform users about this change?
- [ ] Yes
- [ ] No
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
- **Bug Fixes**
- Improved the list widget’s pagination by updating how page numbers are
calculated, ensuring accurate reflection of the current page size
settings.
- **Tests**
- Enhanced test coverage for the list widget's visibility, adding new
tests to validate user interactions and ensuring the widget behaves as
expected when items are selected.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->