Reset model state if setting key changes (#101806)

As the same instance of the object widget could be used for different
settings, it is necessary to make sure to reset the model state (edit
key and selection index) when an instance is reused.

src/vs/workbench/contrib/preferences/browser/settingsTree.ts

@@ -1132,6 +1132,7 @@ export class SettingObjectRenderer extends AbstractSettingRenderer implements IT
 		const items = getObjectDisplayValue(dataElement);
 
 		template.objectWidget.setValue(items, {
+			settingKey: dataElement.setting.key,
 			showAddButton: (
 				typeof dataElement.setting.objectAdditionalProperties === 'object' ||
 				isDefined(dataElement.setting.objectPatternProperties) ||

src/vs/workbench/contrib/preferences/browser/settingsWidgets.ts

@@ -188,7 +188,7 @@ export class ListSettingListModel<TDataItem extends object> {
 		this._dataItems = listData;
 	}
 
-	select(idx: number): void {
+	select(idx: number | null): void {
 		this._selectedIdx = idx;
 	}
 
@@ -664,6 +664,7 @@ export interface IObjectKeySuggester {
 }
 
 interface IObjectSetValueOptions {
+	settingKey: string;
 	showAddButton: boolean;
 	keySuggester: IObjectKeySuggester;
 	valueSuggester: IObjectValueSuggester;
@@ -678,6 +679,7 @@ interface IObjectRenderEditWidgetOptions {
 }
 
 export class ObjectSettingWidget extends AbstractListSettingWidget<IObjectDataItem> {
+	private currentSettingKey: string = '';
 	private showAddButton: boolean = true;
 	private keySuggester: IObjectKeySuggester = () => undefined;
 	private valueSuggester: IObjectValueSuggester = () => undefined;
@@ -686,6 +688,13 @@ export class ObjectSettingWidget extends AbstractListSettingWidget<IObjectDataIt
 		this.showAddButton = options?.showAddButton ?? this.showAddButton;
 		this.keySuggester = options?.keySuggester ?? this.keySuggester;
 		this.valueSuggester = options?.valueSuggester ?? this.valueSuggester;
+
+		if (isDefined(options) && options.settingKey !== this.currentSettingKey) {
+			this.model.setEditKey('none');
+			this.model.select(null);
+			this.currentSettingKey = options.settingKey;
+		}
+
 		super.setValue(listData);
 	}