Visualize running container counts on tree root and group nodes

src/tree/LocalGroupTreeItemBase.ts

@@ -10,7 +10,7 @@
 export abstract class LocalGroupTreeItemBase<TItem extends AnyContainerObject, TProperty extends string | CommonProperty> extends AzExtParentTreeItem {
     public declare readonly parent: LocalRootTreeItemBase<TItem, TProperty>;
     public readonly group: string;
-    private _items: TItem[];
+    protected _items: TItem[];
     private _childTreeItems: AzExtTreeItem[];
 
     public constructor(parent: LocalRootTreeItemBase<TItem, TProperty>, group: string, items: TItem[]) {

src/tree/LocalRootTreeItemBase.ts

@@ -65,7 +65,7 @@
     public descriptionSetting: TProperty[];
     protected failedToConnect: boolean = false;
 
-    private _currentItems: TItem[] | undefined;
+    protected _currentItems: TItem[] | undefined;
     private _cachedItems: TItem[] | undefined;
     private _currentDockerStatus: DockerStatus;
 

src/tree/containers/ContainerGroupTreeItem.ts

@@ -4,7 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import { AzExtTreeItem, IActionContext } from "@microsoft/vscode-azext-utils";
-import { ThemeIcon, TreeItemCollapsibleState } from "vscode";
+import { ThemeIcon, TreeItemCollapsibleState, l10n } from "vscode";
 import { LocalGroupTreeItemBase } from "../LocalGroupTreeItemBase";
 import { LocalRootTreeItemBase } from "../LocalRootTreeItemBase";
 import { getCommonGroupIcon } from "../settings/CommonProperties";
@@ -33,6 +33,14 @@ export class ContainerGroupTreeItem extends LocalGroupTreeItemBase<DockerContain
         return 'containerGroup';
     }
 
+    public get description(): string | undefined {
+        const runningCount = this._items.filter(i => i.state.toLowerCase() === 'running').length;
+        if (runningCount > 0) {
+            return l10n.t('({0}/{1} running)', runningCount, this._items.length);
+        }
+        return undefined;
+    }
+
     public get iconPath(): ThemeIcon {
         switch (this.parent.groupBySetting) {
             case 'ContainerId':

src/tree/containers/ContainersTreeItem.ts

@@ -54,6 +54,14 @@ export class ContainersTreeItem extends LocalRootTreeItemBase<DockerContainerInf
         return this.groupBySetting === 'None' ? l10n.t('container') : l10n.t('container group');
     }
 
+    public get description(): string | undefined {
+        const runningCount = this._currentItems?.filter(i => i.state.toLowerCase() === 'running').length;
+        if (runningCount > 0) {
+            return l10n.t('({0} running)', runningCount);
+        }
+        return undefined;
+    }
+
     public async getItems(context: IActionContext): Promise<DockerContainerInfo[]> {
         const rawResults = await ext.runWithDefaults(client =>
             client.listContainers({ all: true })