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Ext.data.Store.removeAll() does not reset the totalLength property
Currently the totalLength is not reset by the removeAll() function. This causes the problems when you use bind the store to the PagingToolbar. The PaginToolbar.getPageData() depends on the store.getTotalCount() function and this has not been reset when the removeAll is invoked.
This has been posted before.
1. Store doesn't update totalLength on all updates (add, remove removeAll and filter).
2. PagingToolbar doesn't listen to add, remove, clear and datachanged store events to update the info.
My PagingStore user extension includes an extended PagingToolbar that addresses these issues.