QuickPick-Select-Many.ts

import * as vscode from 'vscode';

export async function quickPickItem(items: string[]): Promise<string[]> {
    const options = items.map(item => ({ label: item }));

    return new Promise((resolve, _) => {
        const quickPick = vscode.window.createQuickPick();
        const placeholder = "Select a item.";

        quickPick.placeholder = placeholder;
        quickPick.items = options;
        quickPick.canSelectMany = true;

        let selectedItems = [];

        quickPick.onDidChangeSelection((selected) => {
            selectedItems = selected; // string[]
        });

        quickPick.onDidAccept(_ => {
            // workaround for no activeItems when canSelectMany is true
            resolve(selectedItems);
            quickPick.hide();
        });

        quickPick.onDidHide(_ => quickPick.dispose());
        quickPick.show();
    });
}

async function example() {
    const result = await quickPickItem(['one', 'two', 'three']);
    console.log(result);
}