WorkflowView.AddDesignerMessageFilter(WorkflowDesignerMessageFilter) 方法

定義

命名空間:

System.Workflow.ComponentModel.Design

組件:

System.Workflow.ComponentModel.dll

將 WorkflowDesignerMessageFilter 加入至 WorkflowView。

public:
 void AddDesignerMessageFilter(System::Workflow::ComponentModel::Design::WorkflowDesignerMessageFilter ^ designerMessageFilter);

public void AddDesignerMessageFilter (System.Workflow.ComponentModel.Design.WorkflowDesignerMessageFilter designerMessageFilter);

member this.AddDesignerMessageFilter : System.Workflow.ComponentModel.Design.WorkflowDesignerMessageFilter -> unit

Public Sub AddDesignerMessageFilter (designerMessageFilter As WorkflowDesignerMessageFilter)

參數

designerMessageFilter

WorkflowDesignerMessageFilter

要加入至 WorkflowDesignerMessageFilter 的 WorkflowView。

範例

下列範例中，將建立 WorkflowDesignerLoader，而且 WorkflowView 物件將會與工作流程設計介面產生關聯。 為了取得訊息通知，建立了 WorkflowDesignerMessageFilter 並加入至 WorkflowView 物件。

這個程式碼範例是 WorkflowViewWrapper.cs 檔案中 Outlook Workflow Wizard SDK 範例的一部分。 如需詳細資訊，請參閱 Outlook 工作流程精靈範例。

public WorkflowViewWrapper()
{
    this.loader = new Loader();

    // Create a Workflow Design Surface
    this.surface = new DesignSurface();
    this.surface.BeginLoad(this.loader);

    // Get the Workflow Designer Host
    this.Host = this.surface.GetService(typeof(IDesignerHost)) as IDesignerHost;

    if (this.Host == null)
        return;

    // Create a Sequential Workflow by using the Workflow Designer Host
    SequentialWorkflow = (SequentialWorkflowActivity)Host.CreateComponent(typeof(SequentialWorkflowActivity));
    SequentialWorkflow.Name = "CustomOutlookWorkflow";

    // Create a Workflow View on the Workflow Design Surface
    this.workflowView = new WorkflowView(this.surface as IServiceProvider);

    // Add a message filter to the workflow view, to support panning
    MessageFilter filter = new MessageFilter(this.surface as IServiceProvider, this.workflowView);
    this.workflowView.AddDesignerMessageFilter(filter);

    // Activate the Workflow View
    this.Host.Activate();

    this.workflowView.Dock = DockStyle.Fill;
    this.Controls.Add(workflowView);
    this.Dock = DockStyle.Fill;
}

Public Sub New()

    Me.loaderValue = New Loader()

    ' Create a Workflow Design Surface
    Me.surface = New DesignSurface()
    Me.surface.BeginLoad(Me.loaderValue)

    ' Get the Workflow Designer Host
    If Me.surface.GetService(GetType(IDesignerHost)) IsNot Nothing AndAlso TypeOf Me.surface.GetService(GetType(IDesignerHost)) Is IDesignerHost Then
        Me.Host = CType(Me.surface.GetService(GetType(IDesignerHost)), IDesignerHost)
    Else
        Return
    End If

    ' Create a Sequential Workflow by using the Workflow Designer Host
    SequentialWorkflow = CType(Host.CreateComponent(GetType(SequentialWorkflowActivity)), SequentialWorkflowActivity)
    SequentialWorkflow.Name = "CustomOutlookWorkflow"

    ' Create a Workflow View on the Workflow Design Surface
    Me.workflowView = New WorkflowView(CType(Me.surface, IServiceProvider))

    ' Add a message filter to the workflow view, to support panning
    Dim filter As MessageFilter = New MessageFilter(CType(Me.surface, IServiceProvider), Me.workflowView)
    Me.workflowView.AddDesignerMessageFilter(filter)

    ' Activate the Workflow View
    Me.Host.Activate()

    Me.workflowView.Dock = DockStyle.Fill
    Me.Controls.Add(workflowView)
    Me.Dock = DockStyle.Fill
End Sub

先前程式碼建立的 MessageFilter 物件是從 WorkflowDesignerMessageFilter 類別衍生出來的。 透過覆寫此類別的方法，當 WorkflowView 物件發生使用者介面事件時，便會通知訊息篩選條件。

internal sealed class MessageFilter : WorkflowDesignerMessageFilter
{
    private bool mouseDown;
    private IServiceProvider serviceProvider;
    private WorkflowView workflowView;

    public MessageFilter(IServiceProvider provider, WorkflowView view)
    {
        this.serviceProvider = provider;
        this.workflowView = view;
    }

    protected override bool OnMouseDown(MouseEventArgs eventArgs)
    {
        // Allow other components to process this event by not returning true.
        this.mouseDown = true;
        return false;
    }
    protected override bool OnMouseMove(MouseEventArgs eventArgs)
    {
        // Allow other components to process this event by not returning true.
        if (this.mouseDown)
        {
            this.workflowView.ScrollPosition = new Point(eventArgs.X, eventArgs.Y);
        }
        return false;
    }
    protected override bool OnMouseUp(MouseEventArgs eventArgs)
    {
        // Allow other components to process this event by not returning true.
        this.mouseDown = false;
        return false;
    }

    protected override bool OnMouseDoubleClick(MouseEventArgs eventArgs)
    {
        this.mouseDown = false;
        return true;
    }

    protected override bool OnMouseEnter(MouseEventArgs eventArgs)
    {
        // Allow other components to process this event by not returning true.
        this.mouseDown = false;
        return false;
    }

    protected override bool OnMouseHover(MouseEventArgs eventArgs)
    {
        // Allow other components to process this event by not returning true.
        this.mouseDown = false;
        return false;
    }

    protected override bool OnMouseLeave()
    {
        // Allow other components to process this event by not returning true.
        this.mouseDown = false;
        return false;
    }

    protected override bool OnMouseWheel(MouseEventArgs eventArgs)
    {
        this.mouseDown = false;
        return true;
    }

    protected override bool OnMouseCaptureChanged()
    {
        // Allow other components to process this event by not returning true.
        this.mouseDown = false;
        return false;
    }

    protected override bool OnDragEnter(DragEventArgs eventArgs)
    {
        return true;
    }

    protected override bool OnDragOver(DragEventArgs eventArgs)
    {
        return true;
    }

    protected override bool OnDragLeave()
    {
        return true;
    }

    protected override bool OnDragDrop(DragEventArgs eventArgs)
    {
        return true;
    }

    protected override bool OnGiveFeedback(GiveFeedbackEventArgs gfbevent)
    {
        return true;
    }

    protected override bool OnQueryContinueDrag(QueryContinueDragEventArgs qcdevent)
    {
        return true;
    }

    protected override bool OnKeyUp(KeyEventArgs eventArgs)
    {
        return true;
    }

    protected override bool OnShowContextMenu(Point menuPoint)
    {
        return true;
    }

    protected override bool OnKeyDown(KeyEventArgs eventArgs)
    {
        if (eventArgs.KeyCode == Keys.Delete)
        {
            ISelectionService selectionService = (ISelectionService)this.serviceProvider.GetService(typeof(ISelectionService));
            if (selectionService != null && selectionService.PrimarySelection is CodeActivity)
            {
                CodeActivity codeActivityComponent = (CodeActivity)selectionService.PrimarySelection;
                CompositeActivity parentActivity = codeActivityComponent.Parent;
                if (parentActivity != null)
                {
                    parentActivity.Activities.Remove(codeActivityComponent);
                    this.ParentView.Update();
                }
            }
        }
        return true;
    }
}

Friend Class MessageFilter
    Inherits WorkflowDesignerMessageFilter

    Private mouseDown As Boolean
    Private serviceProvider As IServiceProvider
    Private workflowView As WorkflowView

    Public Sub New(ByVal provider As IServiceProvider, ByVal view As WorkflowView)
        Me.serviceProvider = provider
        Me.workflowView = view
    End Sub

    Protected Overrides Function OnMouseDown(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        ' Allow other components to process this event by not returning true.
        Me.mouseDown = True
        Return False
    End Function
    Protected Overrides Function OnMouseMove(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        ' Allow other components to process this event by not returning true.
        If (Me.mouseDown) Then
            Me.workflowView.ScrollPosition = New Point(eventArgs.X, eventArgs.Y)
        End If
        Return False
    End Function
    Protected Overrides Function OnMouseUp(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        ' Allow other components to process this event by not returning true.
        Me.mouseDown = False
        Return False
    End Function

    Protected Overrides Function OnMouseDoubleClick(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        Me.mouseDown = False
        Return True
    End Function

    Protected Overrides Function OnMouseEnter(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        ' Allow other components to process this event by not returning true.
        Me.mouseDown = False
        Return False
    End Function

    Protected Overrides Function OnMouseHover(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        ' Allow other components to process this event by not returning true.
        Me.mouseDown = False
        Return False
    End Function

    Protected Overrides Function OnMouseLeave() As Boolean
        ' Allow other components to process this event by not returning true.
        Me.mouseDown = False
        Return False
    End Function

    Protected Overrides Function OnMouseWheel(ByVal eventArgs As System.Windows.Forms.MouseEventArgs) As Boolean
        Me.mouseDown = False
        Return True
    End Function

    Protected Overrides Function OnMouseCaptureChanged() As Boolean
        ' Allow other components to process this event by not returning true.
        Me.mouseDown = False
        Return False
    End Function

    Protected Overrides Function OnDragEnter(ByVal eventArgs As System.Windows.Forms.DragEventArgs) As Boolean
        Return True
    End Function

    Protected Overrides Function OnDragOver(ByVal eventArgs As System.Windows.Forms.DragEventArgs) As Boolean
        Return True
    End Function

    Protected Overrides Function OnDragLeave() As Boolean
        Return True
    End Function

    Protected Overrides Function OnDragDrop(ByVal eventArgs As System.Windows.Forms.DragEventArgs) As Boolean
        Return True
    End Function

    Protected Overrides Function OnGiveFeedback(ByVal eventArgs As System.Windows.Forms.GiveFeedbackEventArgs) As Boolean
        Return True
    End Function

    Protected Overrides Function OnQueryContinueDrag(ByVal eventArgs As System.Windows.Forms.QueryContinueDragEventArgs) As Boolean
        Return True
    End Function

    Protected Overrides Function OnKeyUp(ByVal eventArgs As System.Windows.Forms.KeyEventArgs) As Boolean
        Return True
    End Function

    Protected Overrides Function OnShowContextMenu(ByVal screenMenuPoint As System.Drawing.Point) As Boolean
        Return True
    End Function

    Protected Overrides Function OnKeyDown(ByVal eventArgs As System.Windows.Forms.KeyEventArgs) As Boolean
        If eventArgs.KeyCode = Keys.Delete Then
            Dim selectionService As ISelectionService = CType(Me.serviceProvider.GetService(GetType(ISelectionService)), ISelectionService)
            If selectionService IsNot Nothing AndAlso TypeOf selectionService.PrimarySelection Is CodeActivity Then
                Dim codeActivityComponent As CodeActivity = CType(selectionService.PrimarySelection, CodeActivity)
                Dim parentActivity As CompositeActivity = codeActivityComponent.Parent
                If parentActivity IsNot Nothing Then
                    parentActivity.Activities.Remove(codeActivityComponent)
                    Me.ParentView.Update()
                End If
            End If
        End If
        Return True
    End Function
End Class

備註

WorkflowDesignerMessageFilter 是一個處理來自 WorkflowView 之訊息的元件。

使用 Strategy 設計模式，WorkflowView 將傳遞訊息到 WorkflowDesignerMessageFilter 以進行處理。

滑鼠事件 (Mouse Event)、鍵盤事件、繪製和配置事件將傳送到與 關聯的 。