View not showing up when an extension command is typed/selected - visual-studio-code

Question

I'm creating a vscode client extension that needs to show
Shows a webview on the Primary Sidebar (already works)
Opens a view when a certain extension command is selected (it fails)
The package.json looks like this
"activationEvents": [
"onView:navCode.search",
"onLanguage:typescript",
"onCommand:navCode.start"
],
"main": "./dist/extension",
"contributes": {
"commands": [
{
"command": "navCode.start",
"title": "Show class diagram",
"category": "NavCode Diagram"
}
],
"viewsContainers": {
"activitybar": [
{
"id": "nav-code-search",
"title": "Nav Code",
"icon": "images/nav-code-logo.png"
}
]
},
"views": {
"nav-code-search": [
{
"type": "webview",
"id": "navCode.search",
"name": "Code search"
}
]
}
},
The activate method of my extension looks like these
export function activate(context: vscode.ExtensionContext) {
let refManager = new ReferenceManager();
refManager.updateWorkspaceReferences();
//Register the webview for code nav search
const provider = new SearchViewProvider(context.extensionUri, context, refManager);
context.subscriptions.push(
vscode.window.registerWebviewViewProvider(SearchViewProvider.viewType, provider)
);
context.subscriptions.push(// Create and show a new webview
vscode.commands.registerCommand('navCode.start', () => {
const panel = vscode.window.createWebviewPanel(
'navCode', // Identifies the type of the webview. Used internally
'NavCode - Class Diagram', // Title of the panel displayed to the user
vscode.ViewColumn.One, // Editor column to show the new webview panel in.
{} // Webview options. More on these later.
);
})
);
}
The command appears correctly
But when is selected it shows this error
There is nothing else on Console or Output views, what could be causing this ?
I have searched without any success about how to register multiple views of the same extension
UPDATE
But back to the problem I believe that is realted to this method
refManager.updateWorkspaceReferences();
Because it awaits until a typescript parses all the *.ts files of the current workspace
public async updateWorkspaceReferences() {
let message: string;
let folders = vscode.workspace.workspaceFolders;
if (folders && folders.length > 0) {
message = await this.processProject(folders[0]);
}
else {
message = 'nav-code requires an open workspace to work';
}
this.log.append(message);
}
How can a have a running task, right after the extension is activated ? can I use threads ?

Answer 1

Here is an overview of what I ended up doing to solve the problem
Put the long-running logic inside the SearchViewProvider (not running directly inside the activate method but as a promise that notifies when done
SearchViewProvider gets notified by ReferenceManager that the long-running logic has finished using BehaviorSubject (rxjs) : referencesUpdated
The view is initialized with a default content when notified the content is refreshed.
Here is the relevant code
extension.ts
export function activate(context: vscode.ExtensionContext) {
//Register the webview for code nav search
const provider = new SearchViewProvider(context, logger);
context.subscriptions.push(
vscode.window.registerWebviewViewProvider(SearchViewProvider.viewType, provider)
);
context.subscriptions.push(// Create and show a new webview
vscode.commands.registerCommand('navCode.start', () => {
const panel = vscode.window.createWebviewPanel(
'navCode', // Identifies the type of the webview. Used internally
'NavCode - Class Diagram', // Title of the panel displayed to the user
vscode.ViewColumn.One, // Editor column to show the new webview panel in.
{} // Webview options. More on these later.
);
})
);
}
SearchViewProvider.ts
constructor(
private context: vscode.ExtensionContext,
private logger: Logger
) {
this.extensionUri = this.context.extensionUri;
this.referenceManager = new ReferenceManager(logger);
this.referenceManager.referencesUpdated.subscribe(() => { this.refreshView() });
}
public resolveWebviewView(webview: vscode.WebviewView, context: vscode.WebviewViewResolveContext<unknown>, token: vscode.CancellationToken): void | Thenable<void> {
this.view = webview;
if (this.view) {
/** existing view logic **/
this.refreshView();
}
}
refreshView() {
if (this.view) {
this.view.webview.html = this.buildView(this.view.webview);
}
}