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FlexGridFilter Class

FlexGridFilter Class

Implements an Excel-style filter for FlexGrid controls.

To enable filtering on a FlexGrid control, create an instance of the FlexGridFilter and pass the grid as a parameter to the constructor. For example:

import { FlexGrid } from '@mescius/wijmo.grid';
import { FlexGridFilter } from '@mescius/wijmo.grid.filter';
let flex = new FlexGrid('#theGrid'); // create the grid
let filter = new FlexGridFilter(flex); // add a filter to the grid

Once this is done, a filter icon is added to the grid's column headers. Clicking the icon shows an editor where the user can edit the filter conditions for that column.

The FlexGridFilter class depends on the wijmo.grid and wijmo.input modules.

The example below shows how you can use a FlexGridFilter to add filtering to a FlexGrid control:

Example

Heirarchy

Constructors

constructor

Properties

activeEditor

activeEditor: ColumnFilterEditor

Gets the active ColumnFilterEditor.

This property allows you to customize the filter editor when handling the filterChanging event. It returns null when no filters are being edited.

defaultFilterType

defaultFilterType: FilterType

Gets or sets the default filter type to use.

This value can be overridden in filters for specific columns. For example, the code below creates a filter that filters by conditions on all columns except the "ByValue" column:

import { FlexGridFilter, FilterType } from '@mescius/wijmo.grid.filter';
let filter = new FlexGridFilter(flex);
filter.defaultFilterType = FilterType.Condition;
let col = flex.getColumn('ByValue'),
    cf = filter.getColumnFilter(col);
cf.filterType = FilterType.Value;

The default value for this property is FilterType.Both.

exclusiveValueSearch

exclusiveValueSearch: boolean

Gets or sets a value that determines whether the filter should include only values selected by the ValueFilter.filterText property.

The default value for this property is true, which matches Excel's behavior.

Set it to false to disable this behavior, so searching only affects which items are displayed on the list and not which items are included in the filter.

filterColumns

filterColumns: string[]

Gets or sets an array containing the names or bindings of the columns that have filters.

Setting this property to null or to an empty array adds filters to all columns.

filterDefinition

filterDefinition: string

Gets or sets the current filter definition as a JSON string.

The filterDefinition includes information about all currently active column filters. It does not include data maps because data maps are not serializable.

grid

grid: FlexGrid

Gets a reference to the FlexGrid that owns this filter.

reApplyFilterOnUpdate

reApplyFilterOnUpdate: boolean

Gets or sets a value indicating whether to apply filter on the updated rows. If this property is set to true, then events such as row update, row insertion, sorting etc refreshes filter and rows which do not pass filter gets filtered out. IF this property is set to false, then filter is not applied immediately and we need to click the apply button again to refresh filter. For complete excel behavior you also need to set the refreshOnEdit property CollectionView.refreshOnEdit of CollectionView to false ```typescript // For flexgrid flexgrid.collectionView.refreshOnEdit = false;

// For flexsheet flexSheet.itemsSourceChanged.addHandler((s, e) => { if(s.collectionView){ s.collectionView.refreshOnEdit = false; } });


The default value for this property is **false**.

showFilterIcons

showFilterIcons: boolean

Gets or sets a value indicating whether the FlexGridFilter adds filter editing buttons to the grid's column headers.

If you set this property to false, then you are responsible for providing a way for users to edit, clear, and apply the filters.

The default value for this property is true.

showSortButtons

showSortButtons: boolean

Gets or sets a value indicating whether the filter editor should include sort buttons.

By default, the editor shows sort buttons like Excel does. But since users can sort columns by clicking their headers, sort buttons in the filter editor may not be desirable in some circumstances.

The default value for this property is true.

Methods

apply

  • apply(): void
  • Applies the current column filters to the grid.

    Returns void

clear

  • clear(): void
  • Clears all column filters.

    Returns void

closeEditor

  • closeEditor(): void
  • Closes the filter editor.

    Returns void

editColumnFilter

  • editColumnFilter(col: any, ht?: HitTestInfo, ref?: HTMLElement): void
  • Shows the filter editor for the given grid column.

    Parameters

    • col: any

      The Column that contains the filter to edit.

    • Optional ht: HitTestInfo

      A wijmo.grid.HitTestInfo object containing the range of the cell that triggered the filter display.

    • Optional ref: HTMLElement

      An HTMLElement to use as a reference for positioning the editor.

    Returns void

getColumnFilter

  • Gets the filter for the given column.

    Parameters

    • col: Column | string | number

      The Column that the filter applies to (or column name or index). If the specified column does not exist, the method returns null.

    • Optional create: boolean

      Whether to create the filter if it does not exist.

    Returns ColumnFilter

onEditingFilter

onExclusiveValueSearchChanged

  • onExclusiveValueSearchChanged(e?: EventArgs): void

onFilterApplied

onFilterChanged

onFilterChanging

Events

editingFilter

editingFilter: Event<FlexGridFilter, EventArgs>

Occurs when a column filter is about to be edited by the user. Use this event to customize the column filter if you want to override the default settings for the filter.

This event fires before the filter editor is created, so the activeEditor property is null at this point. If you want to customize the editor, use the filterChanging event.

For example, the code below customizes the list of country names in the value filter editor so "Italy" is always the first value:

new FlexGridFilter(theGrid, {
    editingFilter: (s, e) => {
        if (e.getColumn().binding == 'country') {

            // start with Italy
            let vals = ["Italy"];

            // append other unique values (except Italy)
            let valueFilter = s.getColumnFilter("country", true).valueFilter;
            valueFilter.uniqueValues = null;
            valueFilter.getUniqueValues().forEach(item => {
                if (item.text != "Italy") {
                    vals.push(item.text);
                }
            });

            // assign custom unique value list to the valueFilter
            valueFilter.uniqueValues = vals;
            valueFilter.sortValues = false;
        }
    }
});

exclusiveValueSearchChanged

exclusiveValueSearchChanged: Event<FlexGridFilter, EventArgs>

Occurs after the exclusiveValueSearch is changed.

filterApplied

filterApplied: Event<FlexGridFilter, EventArgs>

Occurs after the filter is applied.

filterChanged

Occurs after a column filter has been edited by the user.

Use the event parameters to determine the column that owns the filter and whether changes were applied or canceled.

filterChanging

Occurs when a column filter is about to be edited by the user.

Use this event to customize the filter editor if you want to override its default settings. You can use the activeEditor property to get a reference to the currently active filter editor.

For example, the code below applies a custom sort to the list of country names in the value filter editor so "Italy" is always the first value:

new FlexGridFilter(theGrid, {
    filterChanging: (s, e) => {
        if (e.getColumn().binding == "country") {
            let edt = s.activeEditor,
                lbHost = edt.hostElement.querySelector('[wj-part=div-values]'),
                lb = Control.getControl(lbHost) as ListBox;
            (lb.collectionView as CollectionView).sortComparer = (a: any, b: any) => {
                if (a != b) { // sort Italy first
                    if (a == 'Italy') return -1;
                    if (b == 'Italy') return +1;
                }
                return null; // use default sort order
            }
            lb.collectionView.refresh();
        }
    },
});