API Reference > imodeljs-frontend > QuantityFormatting > BaseUnitFormattingSettingsProvider BaseUnitFormattingSettingsProvider Class Beta This abstract class reacts to changes in the "active" iModel and updates the QuantityFormatter overrides and active presentation unit system based on stored preferences. In addition, monitors the QuantityFormatter for changes to format overrides and the active unit system and stores these changes. The "active" iModel is determined by listening to the IModelApp.viewManager.onSelectedViewportChanged event and gets the iModel from the selected viewport. Extended by LocalUnitFormatProvider Implements UnitFormattingSettingsProvider Methods Name Description constructor(_quantityFormatter: QuantityFormatter, _maintainOverridesPerIModel?: boolean): BaseUnitFormattingSettingsProvider Beta applyQuantityFormattingSettingsForIModel(imodel?: IModelConnection): Promise<void> Protected buildQuantityFormatOverridesMap(): Promise<Map<UnitSystemKey, Map<string, FormatProps>>> Protected function to convert from serialized JSON format for Quantity Type overrides to build a map compatible with QuantityManager loadOverrides(imodel?: IModelConnection): Promise<void> Function to load overrides for a specific IModelConnection. remove(quantityTypeKey: string): Promise<boolean> Abstract Removes the override formats for a specific quantity type. retrieve(quantityTypeKey: string): Promise<undefined | OverrideFormatEntry> Abstract Retrieves serialized JSON object containing format overrides for a specific quantity type. retrieveUnitSystem(defaultKey: UnitSystemKey): Promise<UnitSystemKey> Abstract Retrieves the active unit system typically based on the "active" iModelConnection. store(quantityTypeKey: string, overrideProps: OverrideFormatEntry): Promise<boolean> Abstract Serializes JSON object containing format overrides for a specific quantity type. storeFormatOverrides(__namedParameters: QuantityFormatOverridesChangedArgs): Promise<void> function called to save format overrides storeUnitSystemKey(unitSystemKey: UnitSystemKey): Promise<boolean> Abstract Store the active unit system typically for the "active" iModelConnection. storeUnitSystemSetting(__namedParameters: FormattingUnitSystemChangedArgs): Promise<void> save UnitSystem for active iModel Properties Name Type Description _imodelConnection Protected undefined | IModelConnection imodelConnection Accessor ProtectedReadOnly undefined | IModelConnection maintainOverridesPerIModel Accessor ReadOnly boolean property that is set by the implementation to inform the BaseUnitFormattingSettingsProvider if the provider Defined in core/frontend/src/quantity-formatting/BaseUnitFormattingSettingsProvider.ts Line 23 Last Updated: 12 June, 2024