showing-background-progress

Showing Progress for Background Tasks in Visual Studio Extensions

When your extension performs long-running work, you must show progress to the user so they know the operation is in progress and how far along it is. Visual Studio provides several progress UI mechanisms — choosing the right one depends on how much attention the task demands.

Without progress feedback, users assume the IDE is frozen and may force-quit Visual Studio, losing unsaved work. The VS progress APIs handle threading, cancellation, and UI placement automatically — building your own progress UI from scratch means duplicating all of that. The Task Status Center is the standard location users have learned to check (NuGet restore, project load, and indexing all use it), so extensions that report progress there feel native rather than bolted on.

When to use this vs. alternatives:

• Long-running background work with progress reporting → this skill (Task Status Center / ProgressReporter)
• One-shot status update ("operation completed") → status bar message (see vs-message-box)
• Blocking confirmation before or after an operation → message box (see vs-message-box)
• Non-blocking notification that persists → info bar (see vs-info-bar)
• Error or warning to surface in the Error List → vs-error-list

Decision guide: which progress UI to use

Mechanism	Blocking?	When to use	User attention
Status bar progress	No	Quick background tasks (< 10 s)	Low — user doesn't need to act
Task Status Center	No	Long-running background tasks (indexing, analysis, sync)	Low — appears in bottom-left corner, user can check anytime
Threaded Wait Dialog	Semi-blocking	Tasks the user must wait for but shouldn't freeze the IDE	Medium — modal dialog appears after a delay
ProgressReporter (Extensibility)	No	Out-of-process extensions that need non-blocking progress	Low — displayed in the Task Status Center

Rule of thumb: Prefer non-blocking progress (status bar or Task Status Center). Use the Threaded Wait Dialog only when the user initiated an action and must wait for the result before continuing.

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1. VisualStudio.Extensibility (out-of-process, recommended)

Use ShellExtensibility.StartProgressReportingAsync() to start progress reporting. It returns a ProgressReporter (implements IProgress<ProgressStatus> and IDisposable) that displays progress in the VS Task Status Center.

NuGet package: Microsoft.VisualStudio.Extensibility Key namespaces: Microsoft.VisualStudio.Extensibility.Shell, Microsoft.VisualStudio.RpcContracts.ProgressReporting

Progress from a command

[VisualStudioContribution]
internal class AnalyzeCommand : Command
{
    public AnalyzeCommand(VisualStudioExtensibility extensibility)
        : base(extensibility) { }

    public override CommandConfiguration CommandConfiguration => new("Analyze Solution")
    {
        Placements = [CommandPlacement.KnownPlacements.ToolsMenu],
        Icon = new(ImageMoniker.KnownValues.Search, IconSettings.IconAndText),
    };

    public override async Task ExecuteCommandAsync(
        IClientContext context, CancellationToken ct)
    {
        using ProgressReporter progress = await this.Extensibility.Shell()
            .StartProgressReportingAsync("Analyzing solution", ct);

        progress.Report(new ProgressStatus(percentComplete: 0, "Starting analysis..."));

        await Task.Delay(1000, ct); // Step 1
        progress.Report(new ProgressStatus(percentComplete: 33, "Scanning files..."));

        await Task.Delay(1000, ct); // Step 2
        progress.Report(new ProgressStatus(percentComplete: 66, "Processing results..."));

        await Task.Delay(1000, ct); // Step 3
        progress.Report(new ProgressStatus(percentComplete: 100, "Complete"));
    }
}

Cancellable progress

Pass ProgressReporterOptions to make the task cancellable by the user:

using ProgressReporter progress = await this.Extensibility.Shell()
    .StartProgressReportingAsync(
        "Long running task",
        new ProgressReporterOptions(isWorkCancellable: true),
        ct);

progress.Report(new ProgressStatus(percentComplete: 0, "Working..."));

Indeterminate progress (unknown total)

Pass null for percentComplete to show an indeterminate spinner:

progress.Report(new ProgressStatus(percentComplete: null, "Scanning..."));

---

2. VSIX Community Toolkit (in-process)

The Community Toolkit provides three progress mechanisms via simple static APIs.

NuGet package: Community.VisualStudio.Toolkit Key namespace: Community.VisualStudio.Toolkit

a) Status bar progress

The simplest option. Shows a progress bar integrated into the status bar at the bottom of the VS window. Non-blocking — the user can continue working.

protected override async Task ExecuteAsync(OleMenuCmdEventArgs e)
{
    var totalSteps = 5;

    for (int currentStep = 1; currentStep <= totalSteps; currentStep++)
    {
        await VS.StatusBar.ShowProgressAsync(
            $"Processing step {currentStep}/{totalSteps}",
            currentStep,
            totalSteps);

        await Task.Delay(1000); // Simulate work
    }

    // Progress automatically clears when currentStep == totalSteps
}

To show a simple text message without a progress bar:

await VS.StatusBar.ShowMessageAsync("Operation completed successfully.");

To start and stop a status bar animation:

await VS.StatusBar.StartAnimationAsync(StatusAnimation.Build);
// ... do work ...
await VS.StatusBar.EndAnimationAsync(StatusAnimation.Build);

b) Task Status Center

The Task Status Center (TSC) is the icon area at the bottom-left of the status bar. It's designed for long-running background tasks (like indexing, NuGet restores, etc.). Tasks are listed when the user clicks the icon. Non-blocking and supports cancellation.

protected override async Task ExecuteAsync(OleMenuCmdEventArgs e)
{
    await StartBackgroundTaskAsync();
}

private async Task StartBackgroundTaskAsync()
{
    IVsTaskStatusCenterService tsc = await VS.Services.GetTaskStatusCenterAsync();

    var options = default(TaskHandlerOptions);
    options.Title = "Analyzing solution";
    options.ActionsAfterCompletion = CompletionActions.None;

    TaskProgressData data = default;
    data.CanBeCanceled = true;

    ITaskHandler handler = tsc.PreRegister(options, data);
    Task task = DoLongRunningWorkAsync(data, handler);
    handler.RegisterTask(task);
}

private async Task DoLongRunningWorkAsync(TaskProgressData data, ITaskHandler handler)
{
    float totalSteps = 5;

    for (float currentStep = 1; currentStep <= totalSteps; currentStep++)
    {
        // Check for cancellation
        if (handler.UserCancellation.IsCancellationRequested)
        {
            data.PercentComplete = (int)(currentStep / totalSteps * 100);
            data.ProgressText = "Cancelled";
            handler.Progress.Report(data);
            return;
        }

        await Task.Delay(1000);

        data.PercentComplete = (int)(currentStep / totalSteps * 100);
        data.ProgressText = $"Step {currentStep} of {totalSteps} completed";
        handler.Progress.Report(data);
    }
}

Task Status Center — key concepts:

Concept	Description
TaskHandlerOptions.Title	Text shown in the TSC list
TaskProgressData.CanBeCanceled	If true, user can cancel via the TSC UI
TaskProgressData.PercentComplete	0–100 integer for the progress bar
TaskProgressData.ProgressText	Dynamic text shown under the title
CompletionActions.None	Task disappears from the list when done
CompletionActions.RetainOnFaulted	Keep the entry visible if the task throws
handler.UserCancellation	CancellationToken triggered when user clicks Cancel
handler.PreRegister / RegisterTask	Pre-register shows the task immediately; RegisterTask links the actual Task

c) Threaded Wait Dialog

A modal dialog that appears only after a configurable delay (e.g., 1 second). It writes progress to the status bar while waiting for the delay, then shows a dialog. Use this when the user initiated an action and must wait for it to finish.

protected override async Task ExecuteAsync(OleMenuCmdEventArgs e)
{
    var factory = await VS.Services.GetThreadedWaitDialogAsync() as IVsThreadedWaitDialogFactory;
    IVsThreadedWaitDialog4 dialog = factory.CreateInstance();

    // Show the dialog after 1 second of waiting
    dialog.StartWaitDialog(
        szWaitCaption: "Processing",
        szWaitMessage: "Please wait while the operation completes...",
        szProgressText: "",
        varStatusBmpAnim: null,
        szStatusBarText: "Processing...",
        iDelayToShowDialog: 1,       // seconds before the dialog appears
        fIsCancelable: true,
        fShowMarqueeProgress: false);

    var totalSteps = 5;

    for (int currentStep = 1; currentStep <= totalSteps; currentStep++)
    {
        dialog.UpdateProgress(
            szUpdatedWaitMessage: "Please wait...",
            szProgressText: $"Step {currentStep}/{totalSteps}",
            szStatusBarText: $"Step {currentStep}/{totalSteps}",
            iCurrentStep: currentStep,
            iTotalSteps: totalSteps,
            fDisableCancel: false,
            out bool cancelled);

        if (cancelled) break;

        await Task.Delay(1000); // Simulate work
    }

    // Dismiss the dialog
    (dialog as IDisposable).Dispose();
}

Important: The Threaded Wait Dialog keeps the UI thread responsive (unlike a raw Thread.Sleep) — VS continues pumping messages. But the modal dialog blocks user interaction with the IDE.

---

3. VSSDK (in-process, legacy)

The raw VSSDK APIs for the same three mechanisms. Use these when you don't have the Community Toolkit.

NuGet package: Microsoft.VisualStudio.SDK Key namespaces: Microsoft.VisualStudio.Shell, Microsoft.VisualStudio.Shell.Interop

a) Status bar progress

await ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();

IVsStatusbar statusBar = (IVsStatusbar)Package.GetGlobalService(typeof(SVsStatusbar));

uint cookie = 0;
int totalSteps = 5;

// Initialize the progress bar
statusBar.Progress(ref cookie, 1, "", 0, 0);

for (uint currentStep = 1; currentStep <= totalSteps; currentStep++)
{
    statusBar.Progress(ref cookie, 1, $"Step {currentStep}/{totalSteps}", currentStep, (uint)totalSteps);
    await Task.Delay(1000);
}

// Clear the progress bar
statusBar.Progress(ref cookie, 0, "", 0, 0);

Status bar text only (no progress bar):

IVsStatusbar statusBar = (IVsStatusbar)Package.GetGlobalService(typeof(SVsStatusbar));
statusBar.SetText("Operation completed.");

b) Task Status Center

private async Task StartBackgroundTaskAsync()
{
    var tsc = (IVsTaskStatusCenterService)await AsyncServiceProvider.GlobalProvider
        .GetServiceAsync(typeof(SVsTaskStatusCenterService));

    var options = default(TaskHandlerOptions);
    options.Title = "Indexing project files";
    options.ActionsAfterCompletion = CompletionActions.None;

    TaskProgressData data = default;
    data.CanBeCanceled = true;

    ITaskHandler handler = tsc.PreRegister(options, data);
    Task task = DoLongRunningWorkAsync(data, handler);
    handler.RegisterTask(task);
}

private async Task DoLongRunningWorkAsync(TaskProgressData data, ITaskHandler handler)
{
    float totalSteps = 10;

    for (float currentStep = 1; currentStep <= totalSteps; currentStep++)
    {
        if (handler.UserCancellation.IsCancellationRequested) return;

        await Task.Delay(500);

        data.PercentComplete = (int)(currentStep / totalSteps * 100);
        data.ProgressText = $"Indexed {currentStep} of {totalSteps} files";
        handler.Progress.Report(data);
    }
}

c) Threaded Wait Dialog

await ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();

var factory = (IVsThreadedWaitDialogFactory)Package.GetGlobalService(typeof(SVsThreadedWaitDialogFactory));
IVsThreadedWaitDialog2 dialog;
factory.CreateInstance(out dialog);

dialog.StartWaitDialog(
    "Processing",                          // caption
    "Working on it...",                    // message
    "",                                     // progress text
    null,                                   // status bar animation
    "",                                     // status bar text
    1,                                      // delay in seconds
    true,                                   // cancelable
    true);                                  // show marquee

int totalSteps = 5;

for (int i = 1; i <= totalSteps; i++)
{
    bool cancelled;
    dialog.HasCanceled(out cancelled);
    if (cancelled) break;

    dialog.UpdateProgress(
        "Working...",
        $"Step {i}/{totalSteps}",
        $"Step {i}/{totalSteps}",
        i,
        totalSteps,
        false,                              // disable cancel
        out cancelled);

    await Task.Delay(1000);
}

dialog.EndWaitDialog(out int cancelledResult);

---

Complete pattern: combining progress with error handling

Community Toolkit example

protected override async Task ExecuteAsync(OleMenuCmdEventArgs e)
{
    // Start a Task Status Center entry for the background work
    IVsTaskStatusCenterService tsc = await VS.Services.GetTaskStatusCenterAsync();

    var options = default(TaskHandlerOptions);
    options.Title = "Deploying extension";
    options.ActionsAfterCompletion = CompletionActions.RetainOnFaulted;

    TaskProgressData data = default;
    data.CanBeCanceled = true;

    ITaskHandler handler = tsc.PreRegister(options, data);

    Task task = Task.Run(async () =>
    {
        try
        {
            float totalSteps = 3;

            data.ProgressText = "Packaging...";
            data.PercentComplete = 0;
            handler.Progress.Report(data);
            await PackageAsync(handler.UserCancellation);

            data.ProgressText = "Uploading...";
            data.PercentComplete = 33;
            handler.Progress.Report(data);
            await UploadAsync(handler.UserCancellation);

            data.ProgressText = "Verifying...";
            data.PercentComplete = 66;
            handler.Progress.Report(data);
            await VerifyAsync(handler.UserCancellation);

            data.ProgressText = "Done!";
            data.PercentComplete = 100;
            handler.Progress.Report(data);

            await VS.StatusBar.ShowMessageAsync("Deployment completed successfully.");
        }
        catch (OperationCanceledException)
        {
            await VS.StatusBar.ShowMessageAsync("Deployment cancelled.");
        }
        catch (Exception ex)
        {
            await ex.LogAsync();
            await VS.StatusBar.ShowMessageAsync("Deployment failed. See Output window.");
        }
    });

    handler.RegisterTask(task);
}

---

Key guidance

• Never block the UI thread with Thread.Sleep or synchronous waits during long operations. Use async/await and one of the progress APIs above.
• Status bar progress is best for quick, non-critical operations (< 10 seconds).
• Task Status Center is best for long-running background work — it's non-blocking, supports cancellation, and the user can check progress at any time. This is what VS uses for NuGet restores and project loading.
• Threaded Wait Dialog is semi-blocking — use it only when the user explicitly initiated an action and needs to wait.
• Always support cancellation for operations that take more than a few seconds.
• Use CompletionActions.RetainOnFaulted to keep failed tasks visible in the Task Status Center so the user can see the error.
• The VisualStudio.Extensibility progress API is the simplest — just call progress.Report() with the current step.

Troubleshooting

• Progress bar doesn't appear (Extensibility): Verify you're calling StartProgressReportingAsync and then progress.Report(...) with incremented step values. The Task Status Center won't display until the first Report call.
• Task Status Center entry disappears immediately: The ProgressReporter was disposed (or the using block ended) before the work completed. Ensure the using block wraps the entire async operation.
• Threaded Wait Dialog never shows: The dialog has a built-in delay (~2 seconds) before appearing. If your operation completes before the delay, the dialog is never shown. This is by design — fast operations shouldn't flash a dialog.
• Cancellation doesn't work: Verify you're passing the CancellationToken from the progress API through your entire call chain and checking it between steps with cancellationToken.ThrowIfCancellationRequested().
• Status bar progress stays at 100% after completion: Call VS.StatusBar.ClearAsync() (Toolkit) or reset the status bar after the operation completes.

What NOT to do

Do NOT use Thread.Sleep() or synchronous blocking waits — they freeze the UI thread. Use await Task.Delay() and async patterns.

Do NOT use the Threaded Wait Dialog for operations the user didn't trigger — it's semi-blocking modal. For background tasks, use the Task Status Center.

Do NOT show status bar progress for operations >10 seconds — the status bar is easy to miss and has no cancellation. Use the Task Status Center.

Do NOT forget cancellation support for any operation >a few seconds — always pass CancellationToken through the call chain.

Do NOT silently swallow task failures — use CompletionActions.RetainOnFaulted so failed tasks remain visible.

See also

• vs-async-threading
• vs-message-box
• vs-error-handling
• vs-commands

References

• Progress bars for background tasks (Community Toolkit)
• Notifications and Progress UX Guidelines
• Using the Status Bar