Grid.FixedRowCount := 2;
Grid.InsertRow(1);

Grid.Options.Filtering.Enabled := True;
Grid.Options.Filtering.Controls := [gfcButton, gfcEditor];
Grid.Options.Filtering.Row := 1;

By default, enabling a filter row automatically detects which kind of editor is required. This can be customized at column level by using the following code.

Grid.ColumnByHeader('Joined').AddSetting(gcsFilterEditorType);
Grid.ColumnByHeader('Joined').FilterEditorType := gfetDateTime;

The following types are available

• gfetAutomatic: Automatically detects the value type and chooses one of the other types.
• gfetString: A standard edit for string based values
• gfetBoolean: A checkbox for boolean based values
• gfetDateTime: A date/time picker for TDateTime based values
• gfetFloat: A spinbox for float values
• gfetNumber: A spinbox for number values
• gfetCustom: Specify your own editor

Additionally, when the column width is sufficiently large, a filter type selector and a clear button will appear.

Example 1

In this example, we specified a Status column filter

Programmatically, this corresponds with the following code

Grid.RemoveFilter;
f := Grid.Filter.ColumnFilter[Grid.ColumnIndexByHeader('Status')];
f.&Type := gftEqual;
f.BuildCondition('Office');
Grid.ApplyFilter;

Example 2

In our second example, we use a different filter type, selectable with the drop-down list, next to the filter editor.

Programmatically, this corresponds with the following code

Grid.RemoveFilter;
f := Grid.Filter.ColumnFilter[Grid.ColumnIndexByHeader('Name')];
f.&Type := gftContains;
f.BuildCondition('o');
Grid.ApplyFilter;

Custom Filter Editor

When you are in need for a custom filter editor, you can select the filter type gfetCustom, which enables you to create your own editor via the OnCreateCustomFilterEditor event. Below is a sample to create a combobox which filters the progress column via a selection of ranges.

Grid.BeginUpdate;
Grid.RemoveFilterEditor(MakeCell(Grid.ColumnIndexByHeader('Progress'), 1));
Grid.Columns[Grid.ColumnIndexByHeader('Progress')].FilterEditorType := gfetCustom;
Grid.Columns[Grid.ColumnIndexByHeader('Progress')].AddSetting(gcsFilterEditorType);
Grid.EndUpdate;

function TForm1.GridCreateCustomFilterEditor(Sender: TObject;
  ACell: TTMSFNCDataGridCellCoord): TTMSFNCDataGridCellControl;
var
  cbo: TComboBox;
begin
  Result := TComboBox.Create(nil);
  cbo := TComboBox(Result);
  cbo.Items.Add('');
  cbo.Items.Add('<= 25');
  cbo.Items.Add('> 25 & <= 50');
  cbo.Items.Add('> 50 & <= 75');
  cbo.Items.Add('> 75');
  cbo.OnChange := DoComboChange;
end;

procedure TForm1.DoComboChange(Sender: TObject);
var
  cbo: TComboBox;
  f: TTMSFNCDataGridDataFilterData;
begin
  cbo := TComboBox(Sender);

  Grid.RemoveFilter;
  f := Grid.Filter.ColumnFilter[Grid.ColumnIndexByHeader('Progress')];
  f.Condition := cbo.Text;
  Grid.ApplyFilter;
end;

Chaining Filters

With the filter row as an option on top of the already built-in filtering features there are plenty of ways to browse through the data. If visual filtering is not applicable to your application, programmatic filtering can be an option and in this area we provide a way to chain filter operations together. Let's take the following example, where we find if the Name  contains 'k', the Status equals 'Abroad' and the Progress is smaller than 50.

Grid.ClearFilter;
Grid.Filter.Add(Grid.ColumnIndexByHeader('Name'), gftContains, 'k')
           .&And(Grid.ColumnIndexByHeader('Status'), gftEqual, 'Abroad')
           .&And(Grid.ColumnIndexByHeader('Progress'), gftSmallerThan, '50');
Grid.ApplyFilter;

Conclusion

TMS FNC Data Grid offers powerful filter options including a filter row. This feature allows you to quickly narrow down the data you are interested in. TMS FNC Data Grid is part of the TMS FNC UI Pack.