Understanding proxyItems in RevoGrid

In RevoGrid, managing large datasets efficiently is crucial for performance. One of the core concepts in achieving this is the use of proxyItems, a collection that stores all the items in their original order. This is especially important when dealing with dynamic grid content, where filtering, sorting, and drag-and-drop operations can change the order of visible items, but the underlying data order should be preserved.

What are proxyItems?

proxyItems represent the full set of data that the grid operates on, including both visible and hidden items. Unlike the items collection, which reflects only the currently visible subset of data (after filtering, pagination, or any other transformations), proxyItems holds the complete set of items in their original order. This allows RevoGrid to maintain the integrity of the full dataset while still providing dynamic views to the user.

Key Points:

1. Full Data Representation: proxyItems includes all items in the dataset, even those that are filtered out and not displayed.
2. Efficient Data Handling: It acts as a reference to the full data set, ensuring that operations like sorting, pagination, and filtering can be applied without losing track of the original data.
3. Visible Subset: The items collection reflects only the visible rows or columns based on the grid's current view (e.g., after applying a filter or sorting).

How proxyItems Work with items

The items collection is always a subset of proxyItems. Whenever a user interacts with the grid, such as applying a filter or sorting, RevoGrid will adjust items to reflect the new visible dataset. However, proxyItems remains unchanged and holds the original order.

For example, when a user drags rows to reorder them in the grid, RevoGrid adjusts the order in items for the visible subset, but the full dataset in proxyItems remains intact. This allows for operations like restoring the original order, implementing drag-and-drop sorting, and synchronizing changes between visible and full datasets.

Benefits of Using proxyItems

• Performance Optimization: By separating the full dataset from the visible subset, RevoGrid reduces the need to recompute or shuffle the entire data array when sorting or filtering.
• Flexible Interactions: Operations like drag-and-drop, sorting, and grouping can be performed on the visible items without affecting the underlying data order, which is crucial for maintaining consistency.
• Full Data Integrity: proxyItems guarantees that the original dataset is preserved, making it easy to apply operations like pagination or undo changes.

proxyItems provide an efficient way to handle large datasets in RevoGrid while allowing for flexible grid interactions. By maintaining a clear distinction between the visible subset (items) and the full dataset (proxyItems), RevoGrid enables powerful data management features, ensuring high performance and data integrity in complex grid-based applications.