Next Generation Data Grid for Delphi: Filtering & Sorting



Intro

If you’re developing in Delphi and looking for a powerful, flexible, and highly customizable data grid solution, then TMS FNC Data Grid is the perfect choice. In this blog, we continue on our journey with the TMS FNC Data Grid. The TMS FNC Data Grid offers developers advanced tools for presenting and interacting with data. Among these tools, filtering and sorting stand out as essential features, enabling users to quickly navigate and extract meaningful information from extensive data tables. In this blog post, we’ll explore how to implement filtering and sorting in the TMS FNC Data Grid, providing a step-by-step guide on how to optimize your grid for better data management and user experience.

Sorting

To perform sorting in TMS FNC Data Grid, you typically use the Sort method, which sorts based on column index and direction (ascending or descending). Sorting can be triggered programmatically or through user interaction with the grid, such as clicking on a column header.

Programmatic Sorting

Here's a basic example of sorting a grid programmatically based on a column's data:

Grid.Sort(0, gsdDescending);  // Sort the first column in desc order

In the above code, the Sort method is called with two parameters: - The first parameter is the column index (0 in this case, meaning the first column). - The second parameter is the sorting direction, which can be either gsdAscending, gsdDescending or gsdNone.

Advanced Sorting with Multiple Columns

You can also perform multi-column sorting, where sorting occurs based on multiple columns sequentially.

var
  Columns: TArray<Integer>;
  Directions: TArray<TTMSFNCDataGridSortDirection>;
begin
  // Define columns to sort by
  Columns := TArray<Integer>.Create(0, 1); // Sort by first and second columns

  // Define corresponding sort directions
  Directions := TArray<TTMSFNCDataGridSortDirection>.Create(gsdDescending, gsdAscending);

  // Perform multi-column sorting
  Grid.Sort(Columns, Directions);
end;

Using Custom Sorting Logic

For more complex sorting requirements, you can implement custom sorting by utilizing the OnCustomCompare event, which allows you to define your own logic for comparing values in cells.

procedure TForm1.GridCustomCompare(Sender: TObject; ACol, ARow1, ARow2: Integer; var AResult: Integer);
begin
  // Custom comparison logic for sorting
  if Grid.Floats[ACol, ARow1] > Grid.Floats[ACol, ARow2] then
    AResult := 1
  else if Grid.Floats[ACol, ARow1] < Grid.Floats[ACol, ARow2] then
    AResult := -1
  else
    AResult := 0;
end;

Sorting via Interaction

Grid.Options.Sorting.Enabled := True;

The TMS FNC Data Grid allows you to filter data, enabling users to display only the rows that match specific criteria. This is particularly useful when working with large datasets, where you want to focus on a subset of the data. Filtering can be approached in 2 ways, programmatically or via interaction.

Filter Properties

• Condition: A string value that defines the filter condition, including operators such as `<`, `>`, `&`, `|`, `*`, and `?`.
• CaseSensitive: A Boolean value that specifies whether the condition should be evaluated in a case-sensitive manner.
• Data: Specifies the data to which the filter condition is applied. By default, it is applied to the cell text (`gfcNormal`).
• Prefix: A string that represents the part of the cell text to be ignored at the beginning.
• Suffix: A string that represents the part of the cell text to be ignored at the end.
• Operation: Defines the logical operation applied between this filter condition and the previous one.

Programmatic Filtering

You can enable filtering on the grid by using the ApplyFilter method. To define a filter condition, use the Filter property and set conditions based on specific columns:

var
  fltr: TTMSFNCDataGridDataFilterData;
begin
  // Clear any existing filters
  Grid.Filter.Clear;

  // Add the filter condition (Column 1, value starts with 'A')
  fltr := Grid.Filter.Add;
  fltr.Column := 1; // First column (0-based index)
  fltr.Condition := 'A*'; // Condition: values starting with 'A'

  // Apply the filters
  Grid.ApplyFilter;
end;

var
  fltr: TTMSFNCDataGridDataFilterData;
begin
  Grid.Filter.Clear;

  // Add the first filter condition (Column 1, value starts with 'A')
  fltr := Grid.Filter.Add;
  fltr.Column := 1; // First column (0-based index)
  fltr.Condition := 'A*'; // Condition: values starting with 'A'

  // Add the second filter condition (Column 3, value = 40)
  fltr := Grid.Filter.Add;
  fltr.Column := 3; // Fourth column (0-based index)
  fltr.Condition := '=40'; // Condition: values equal to 40

  // Apply the filters
  Grid.ApplyFilter;
end;

Grid.Options.Filtering.Enabled := True;