Answer to http://www.lostechies.com/blogs/derickbailey/archive/2011/02/01/good-refactoring-patterns-for-simple-ui-logic.aspx

gistfile1.cs

interface IUpdaterUI {
  void UpdateStatus(int? progress = null, string message = null);
  void SoftwareUpdateComplete();
  void DataUpdateComplete();
}

class MyForm : IUpdaterUI {
  public void UpdateStatus(int? progress = null, string message = null) {
    if(progress.HasValue) SetProgress(progress.Value);
    if(message != null) MessageLabel.Do(ctl => ctl.Text = message);
  }
  public void SoftwareUpdateComplete() { this.Do(frm => frm.Close(); }
  public void DataUpdateComplete() { 
    Cancel.Do(ctl => ctl.Hide());
    ContinueButton.Do(ctl => ctl.Show());
  }
  
  private void DownloadUpdates() {
    try {
      new Updater(this).Update();
    } catch(Exception ex) {
      // same error handler code
    }
  }
}

class Updater {
  private readonly IUpdaterUI ui;
  public Updater(IUpdaterUI ui) { this.ui = ui; }
  public void Update() {
    ui.UpdateStatus(progress: 5, message: AvailableUpdate.DownloadingUpdateLabelText);
	
    if(AvailableUpdate.SoftwareUpdateAvailable)
      DoSoftwareUpdate();
    else if(AvailableUpdate.DataUpdateAvailable)
      DoDataUpdate();
  }
  
  private void DoSoftwareUpdate() {
    ui.UpdateStatus(progress: 50);
    UpdateSoftware();
    ui.UpdateStatus(progress: 100);
    ui.SoftwareUpdateCompleted();
  }
  
  private void DoDataUpdate() {
    ui.UpdateStatus(progress: 50);
    UpdateData();
    ui.UpdateStatus(progress: 100, message: AvailableUpdate.DownloadCompleteUpdateLabelText);
    ui.DataUpdateComplete();
  }
}