How do I code a progress bar for Windows 7 to also update itself on the taskbar?

Question

Windows 7 has an AWESOME new feature that applications can report the progress of the current activity through the status bar. For example, when copying file(s) using Windows Explorer, a progress bar is layered on top of the application icon in the task bar and the progress is shown as it updates.

What is the API for exposing the progress bar? Is there MSDN documentation on it?

Answer 1

For below .NET 4, or WinForms in any .NET version

Using the Windows API Code Pack from Microsoft (as Keeron mentioned), it's really simple. You just need to use the TaskbarManager. E.g.

To start the progress:

TaskbarManager.Instance.SetProgressState(TaskbarProgressBarState.Normal);

To update the progress:

TaskbarManager.Instance.SetProgressValue(currentValue, maxProgressValue);

And when when you're done, to end the progress:

TaskbarManager.Instance.SetProgressState(TaskbarProgressBarState.NoProgress);

There is more you can do, but that should get you started and might be all you need.

For .NET 4 and above with WPF

You can use System.Windows.Shell.TaskbarItemInfo. E.g. in the Xaml for your main window, you'll need to add:

<Window.TaskbarItemInfo>
    <TaskbarItemInfo x:Name="taskBarItemInfo" />
</Window.TaskbarItemInfo>

Then to update the progress, you would do something like:

taskBarItemInfo.ProgressState = TaskbarItemProgressState.Normal;

for (int i = 0; i < 100; i++)
{
    taskBarItemInfo.ProgressValue = i / 100.0;
    Thread.Sleep(50); // whatever the 'work' really is
}

taskBarItemInfo.ProgressState = TaskbarItemProgressState.None;

Don't forget that if you're doing the 'work' on a background thread (which is probably a good idea for long running tasks), you will need to switch back to the UI thread to update the taskbar.

Answer 2

There's a good article in MSDN magazine about the new taskbar APIs. And yes, the feature is awesome :-)

Essentially, it's all about implementing IFileOperation. There's a good article about using it in managed code here.

Answer 3

If you plan to use other Windows 7 Taskbar features, another approach would be to use the library from Microsoft: Windows API Code Pack for .NET Framework which is no longer available at the old link, but can be found on nuget.

Answer 4

I've written an article about implementing the Windows 7 Taskbar progress API in C# (see: Windows 7 Taskbar Progress Bar with C# and .NET). The control is open source (BSD) and has example projects for C# and VB.NET.

This way you don't have to convert the C++ code from scratch.