Sunday, October 29, 2006

Work Spaces and Smart Part Info Provider

by Paulo Morgado via Paulo Morgado : C# on 10/29/2006 10:57:33 PM

As I understand it, the MVP (Model/View/Presenter) design pattern states that all presentation decisions are the Presenter's responsibility.

In the CAB world, this should include the Smart Part Info.

But the IWorkspace interface only allows you to provide the Smart Part Info (a class that implements the ISmartPartInfo interface and each work space uses a specific one), or the the smart part (the View in the MVP design pattern) should know what information to provide to the work space it lives in by implementing the ISmartPartInfoProvider interface.

To enable the presenter to provide the smart part info changes need to be made to the IWorkspace interface and its implementations. New Show and ApplySmartPartInfo methods need to be added:

/// <summary>
/// Applies the smartPartInfo to the smartPart.

/// </summary>
void ApplySmartPartInfo(object smartPart, ISmartPartInfoProvider smartPartInfoProvider);
/// <summary>
/// Shows SmartPart using the given SmartPartInfo
/// </summary>
/// <param name="smartPart">Smart part to show.</param>
/// <param name="smartPartInfoProvider"></param>
void Show(object smartPart, ISmartPartInfoProvider smartPartInfoProvider);

And it should be implemented in all the classes that implement IWorkspace:

/// <summary>
/// Applies the smartPartInfo to the smartPart.
/// </summary>
public void ApplySmartPartInfo(object smartPart, ISmartPartInfoProvider smartPartInfoProvider)
{
    Microsoft.Practices.CompositeUI.Utility.Guard.ArgumentNotNull(smartPart, "smartPart");
    Microsoft.Practices.CompositeUI.Utility.Guard.ArgumentNotNull(smartPartInfoProvider, "smartPartInfoProvider");
    ThrowIfUnsupportedSP(smartPart);
    ThrowIfSmartPartNotShownPreviously((TSmartPart)smartPart);

    TSmartPart typedSmartPart = (TSmartPart)smartPart;
    TSmartPartInfo typedSmartPartInfo = GetSupportedSPI(smartPartInfoProvider.GetSmartPartInfo(typeof(TSmartPartInfo)));
    Microsoft.Practices.CompositeUI.Utility.Guard.ArgumentNotNull(typedSmartPartInfo, "typedSmartPartInfo");

    OnApplySmartPartInfo(typedSmartPart, typedSmartPartInfo);
}

/// <summary>
/// Shows SmartPart using the given SmartPartInfo
/// </summary>
/// <param name="smartPart">Smart part to show.</param>
/// <param name="smartPartInfoProvider"></param>
public void Show(object smartPart, ISmartPartInfoProvider smartPartInfoProvider)
{
    Microsoft.Practices.CompositeUI.Utility.Guard.ArgumentNotNull(smartPart, "smartPart");
    Microsoft.Practices.CompositeUI.Utility.Guard.ArgumentNotNull(smartPartInfoProvider, "smartPartInfoProvider");
    ThrowIfUnsupportedSP(smartPart);
       
    TSmartPart typedSmartPart = (TSmartPart)smartPart;

    if (smartParts.Contains(typedSmartPart))
    {
        ApplySmartPartInfo(typedSmartPart, smartPartInfoProvider);
        Activate(typedSmartPart);
    }
    else
    {
        TSmartPartInfo typedSmartPartInfo = GetSupportedSPI(smartPartInfoProvider.GetSmartPartInfo(typeof(TSmartPartInfo)));
        Microsoft.Practices.CompositeUI.Utility.Guard.ArgumentNotNull(typedSmartPartInfo, "typedSmartPartInfo");
        smartParts.Add(typedSmartPart);
        OnShow(typedSmartPart, typedSmartPartInfo);
    }
}