Todo.md

SimpleDataGrid Improvement Tasks

Priority 1: Critical Issues

Task 1.1: Fix Generic Control XAML Usage - COMPLETED

Task 1.2: Add Sorting Support - COMPLETED

Priority 2: Essential Features

Task 2.1: Add Page Navigation Enhancements - COMPLETED

Task 2.2: Improve Filtering API - COMPLETED

Task 2.3: Add Runtime Page Size Changes - COMPLETED

Task 2.4: Add Observability Events - COMPLETED

Priority 3: UX Improvements

Task 3.1: Add Empty State Support - COMPLETED

Task 3.2: Add Search Debouncing Support - COMPLETED

Task 3.3: Add Multi-Column Search - COMPLETED

Priority 4: Performance & Code Quality

Task 4.1: Optimize Filtering Performance - COMPLETED

Task 4.2: Fix Edge Cases and Null Safety - COMPLETED

Task 4.3: Improve Current Page Maintenance - COMPLETED

Priority 5: Documentation & Examples

Task 5.1: Add XML Documentation for All Public Members - COMPLETED

Task 5.2: Create Advanced Usage Examples - PARTIALLY COMPLETED

Problem: README only shows basic usage. The existing Example project is minimal.

Solution: Enhance the Example project with comprehensive demonstrations and update README.

Files to modify:

• README.md
• SimpleDataGrid.Example/MainWindow.xaml
• SimpleDataGrid.Example/MainWindow.xaml.cs
• SimpleDataGrid.Example/MainViewModel.cs
• Create SimpleDataGrid.Example/AdvancedExamplesWindow.xaml (new file)
• Create SimpleDataGrid.Example/AdvancedExamplesWindow.xaml.cs (new file)

Current example features:

• Basic search with wildcards
• Single filter (min age)
• Previous/Next navigation
• Page counter display

Requirements for enhanced example project:

• Add second window for advanced examples (AdvancedExamplesWindow) - COMPLETED
• Add example: Named filters with add/remove UI - COMPLETED
• Add example: Multi-column search across Name, Age, and Id - COMPLETED
• Add example: Sorting with column headers - COMPLETED
• Add example: Page size selector ComboBox (10, 25, 50, 100 items) - COMPLETED
• Add example: "Showing X-Y of Z items" display - COMPLETED
• Add example: Debounced search with TextBox.TextChanged - COMPLETED
• Add example: Jump to page functionality with TextBox and Go button - COMPLETED
• Add example: Handling empty states with message overlay - COMPLETED
• Add example: Custom filter expressions builder - COMPLETED
• Add example: Export current page to CSV button - COMPLETED
• Add button to MainWindow to open AdvancedExamplesWindow - COMPLETED
• Expand Person model with more properties (Email, Department, IsActive, HireDate) - COMPLETED
• Generate 1000+ sample records for better pagination demonstration - COMPLETED

README updates:

• Add screenshots or GIFs of example application
• Add "Quick Start" section with minimal example
• Add "Advanced Examples" section linking to example project
• Include code snippets for each advanced feature
• Add section explaining the Example project structure

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Task 5.3: Add Performance Guidelines Documentation - COMPLETED

Priority 6: Testing

Task 6.1: Add Comprehensive Unit Tests

Problem: Test coverage is incomplete.

Solution: Add thorough unit test suite.

Files to modify:

• SimpleDataGrid.Tests/ directory

Test data context:

• Use similar Person model as Example project
• Test with varying dataset sizes (0, 1, 10, 100, 1000 items)
• Current Example uses 100 items with Age range 20-70

Requirements:

• Test pagination edge cases:
  • Empty collection
  • Single item
  • Exact page size (10 items, 10 per page = 1 page)
  • One item over page size (11 items, 10 per page = 2 pages)
  • Page boundary navigation (first, last, out of bounds)
• Test filter combinations:
  • No filters
  • Single filter
  • Multiple filters (AND logic)
  • Add/remove filters
  • Clear all filters
• Test search functionality:
  • Empty search term
  • No matches
  • Partial matches
  • Wildcards (* and ?)
  • Case sensitivity
  • Special characters
• Test null handling:
  • Null source
  • Null filter
  • Null search selector
  • Null/empty search term
• Test concurrent modifications (if thread-safe)
• Test PropertyChanged events fire correctly for all properties
• Test page boundary conditions (CurrentPage, TotalPages, HasNext, HasPrevious)
• Test sort stability (once sorting is implemented)
• Aim for >90% code coverage
• Use xUnit, NUnit, or MSTest framework (check existing test structure)

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Task 6.2: Add Integration Tests

Problem: No tests for WPF control integration.

Solution: Add WPF integration tests.

Files to modify:

• SimpleDataGrid.Tests/ directory (add new test class)
• Consider creating SimpleDataGrid.Tests/IntegrationTests/ subdirectory

Requirements:

• Test PagedDataGrid control binding with test data
• Test DataGrid column sorting integration
• Test PropertyChanged propagation to UI
• Test memory leaks (event handler cleanup)
• Test thread safety with UI thread (use Dispatcher)
• Test performance with large datasets (10K+ items) in UI
• Use the Person model from Example project for consistency
• Test the example project scenarios programmatically

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Optional Enhancements

Task 7.1: Add Export Functionality

Problem: No way to export data.

Solution: Add export methods for current page or all filtered data.

Files to modify:

• SimpleDataGrid/Pagination/PagedCollection.cs

Requirements:

• Add ExportCurrentPage() returning list of items
• Add ExportAllFiltered() returning all filtered items
• Add ExportToCSV(string filePath) method
• Add ExportToJSON(string filePath) method
• Make export methods async
• Add progress reporting for large exports

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Task 7.2: Implement ICollectionView Interface

Problem: Doesn't integrate seamlessly with WPF's collection view infrastructure.

Solution: Implement ICollectionView for better WPF integration.

Files to modify:

• SimpleDataGrid/Pagination/PagedCollection.cs

Requirements:

• Implement ICollectionView interface
• Support WPF's built-in filtering/sorting through ICollectionView
• Maintain backward compatibility
• Update documentation with ICollectionView usage

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Task 7.3: Add Async Data Loading Support

Problem: Synchronous data loading blocks UI.

Solution: Add async loading capabilities.

Files to modify:

• SimpleDataGrid/Pagination/PagedCollection.cs

Requirements:

• Add SetSourceAsync(Func<Task<IReadOnlyList<T>>> loader) method
• Add RefreshAsync() method
• Add IsLoading property
• Add LoadingChanged event
• Handle cancellation tokens
• Add error handling and retry logic
• Update example with async loading pattern

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Task Execution Notes

Project Structure Context:

• Main library: SimpleDataGrid/ - the NuGet package code
• Tests: SimpleDataGrid.Tests/ - unit and integration tests
• Example app: SimpleDataGrid.Example/ - WPF demo application
  • Current example is minimal (100 records, basic features)
  • Uses workaround: PersonPagedDataGrid : PagedDataGrid<Person>
  • Good starting point for demonstrating enhancements

For each task:

1. Read and understand the current implementation
2. Make changes incrementally
3. Ensure backward compatibility unless noted as breaking change
4. Add/update XML documentation
5. Add/update unit tests in SimpleDataGrid.Tests/
6. Update and test with SimpleDataGrid.Example/ project
7. Update README if user-facing changes
8. Test manually with SimpleDataGrid.Example project
9. Consider edge cases and error handling

Working with Example Project:

• After implementing features, add demonstrations to Example project
• Example project serves as both manual test and documentation
• Keep MainWindow simple for basic usage, add AdvancedExamplesWindow for complex scenarios
• Expand Person model as needed for realistic demonstrations
• Increase sample data size to test pagination effectively (1000+ records recommended)

Breaking Changes:

• Tasks marked as "breaking change" should be grouped together for a major version bump
• Create migration guide for breaking changes
• Consider deprecation warnings before removal
• Update Example project to reflect breaking changes

Testing:

• Run all tests after each task: dotnet test
• Run Example project after each task: dotnet run --project SimpleDataGrid.Example
• Test with both .NET 8 and .NET 9 targets
• Test on different screen sizes and DPI settings
• Verify performance with large datasets (10K+ items)

Documentation:

• Update CHANGELOG.md with each completed task
• Update version number appropriately (semantic versioning)
• Update NuGet package description if functionality changes significantly
• Update Example project code to showcase new features
• Consider recording GIFs/videos of example project for README