Como criar um suplemento que retorne uma interface do usuário

Este exemplo mostra como criar um suplemento que retorna um Windows Presentation Foundation (WPF) para um aplicativo autônomo WPF host.

O suplemento retorna uma interface do usuário que é um controle de usuário WPF. O conteúdo do controle de usuário é um único botão que, quando clicado, exibe uma caixa de mensagem. O aplicativo autônomo WPF hospeda o suplemento e exibe o controle de usuário (retornado pelo suplemento) como o conteúdo da janela principal do aplicativo.

Pré-requisitos

Este exemplo destaca as extensões WPF para o modelo de suplemento do .NET Framework que habilitam esse cenário e pressupõe o seguinte:

  • Conhecimento do modelo de suplemento do .NET Framework, incluindo pipeline, suplemento e desenvolvimento de host. Se você não estiver familiarizado com esses conceitos, consulte Suplementos e extensibilidade. Para ver um tutorial que demonstra a implementação de um pipeline, um suplemento e um aplicativo host, consulte Instrução passo a passo: criando um aplicativo extensível.

  • Conhecimento das extensões WPF para o modelo de suplemento do .NET Framework, que pode ser encontrado aqui: Visão geral dos suplementos do WPF.

Exemplo

Para criar um suplemento que retorna uma interface do usuário do WPF requer código específico para cada segmento de pipeline, o suplemento e o aplicativo host.

Implementando o segmento de pipeline de contrato

Um método deve ser definido pelo contrato para retornar uma interface do usuário e seu valor de retorno deve ser do tipo INativeHandleContract. Isso é demonstrado pelo GetAddInUI método do IWPFAddInContract contrato no código a seguir.

using System.AddIn.Contract;
using System.AddIn.Pipeline;

namespace Contracts
{
    /// <summary>
    /// Defines the services that an add-in will provide to a host application
    /// </summary>
    [AddInContract]
    public interface IWPFAddInContract : IContract
    {
        // Return a UI to the host application
        INativeHandleContract GetAddInUI();
    }
}

Imports System.AddIn.Contract
Imports System.AddIn.Pipeline

Namespace Contracts
    ''' <summary>
    ''' Defines the services that an add-in will provide to a host application
    ''' </summary>
    <AddInContract>
    Public Interface IWPFAddInContract
        Inherits IContract
        ' Return a UI to the host application
        Function GetAddInUI() As INativeHandleContract
    End Interface
End Namespace

Implementando o segmento de pipeline de exibição de suplemento

Como o suplemento implementa as interfaces do usuário que ele fornece como subclasses do , o método no modo de exibição de suplemento que se correlaciona a IWPFAddInView.GetAddInUI deve retornar um valor do FrameworkElementtipo FrameworkElement. O código a seguir mostra a exibição de suplemento do contrato, implementada como uma interface.

using System.AddIn.Pipeline;
using System.Windows;

namespace AddInViews
{
    /// <summary>
    /// Defines the add-in's view of the contract
    /// </summary>
    [AddInBase]
    public interface IWPFAddInView
    {
        // The add-in's implementation of this method will return
        // a UI type that directly or indirectly derives from
        // FrameworkElement.
        FrameworkElement GetAddInUI();
    }
}

Imports System.AddIn.Pipeline
Imports System.Windows

Namespace AddInViews
    ''' <summary>
    ''' Defines the add-in's view of the contract
    ''' </summary>
    <AddInBase>
    Public Interface IWPFAddInView
        ' The add-in's implementation of this method will return
        ' a UI type that directly or indirectly derives from 
        ' FrameworkElement.
        Function GetAddInUI() As FrameworkElement
    End Interface
End Namespace

Implementando o segmento de pipeline do adaptador no lado do suplemento

O método de contrato retorna um , mas o suplemento retorna um INativeHandleContractFrameworkElement (conforme especificado pelo modo de exibição do suplemento). Consequentemente, o FrameworkElement deve ser convertido em um INativeHandleContract antes de cruzar a fronteira de isolamento. Esse trabalho é executado pelo adaptador do lado do suplemento chamando ViewToContractAdapter, conforme mostrado no código a seguir.

using System.AddIn.Contract;
using System.AddIn.Pipeline;
using System.Windows;

using AddInViews;
using Contracts;

namespace AddInSideAdapters
{
    /// <summary>
    /// Adapts the add-in's view of the contract to the add-in contract
    /// </summary>
    [AddInAdapter]
    public class WPFAddIn_ViewToContractAddInSideAdapter : ContractBase, IWPFAddInContract
    {
        IWPFAddInView wpfAddInView;

        public WPFAddIn_ViewToContractAddInSideAdapter(IWPFAddInView wpfAddInView)
        {
            // Adapt the add-in view of the contract (IWPFAddInView)
            // to the contract (IWPFAddInContract)
            this.wpfAddInView = wpfAddInView;
        }

        public INativeHandleContract GetAddInUI()
        {
            // Convert the FrameworkElement from the add-in to an INativeHandleContract
            // that will be passed across the isolation boundary to the host application.
            FrameworkElement fe = this.wpfAddInView.GetAddInUI();
            INativeHandleContract inhc = FrameworkElementAdapters.ViewToContractAdapter(fe);
            return inhc;
        }
    }
}

Imports System.AddIn.Contract
Imports System.AddIn.Pipeline
Imports System.Windows

Imports AddInViews
Imports Contracts

Namespace AddInSideAdapters
    ''' <summary>
    ''' Adapts the add-in's view of the contract to the add-in contract
    ''' </summary>
    <AddInAdapter>
    Public Class WPFAddIn_ViewToContractAddInSideAdapter
        Inherits ContractBase
        Implements IWPFAddInContract
        Private wpfAddInView As IWPFAddInView

        Public Sub New(ByVal wpfAddInView As IWPFAddInView)
            ' Adapt the add-in view of the contract (IWPFAddInView) 
            ' to the contract (IWPFAddInContract)
            Me.wpfAddInView = wpfAddInView
        End Sub

        Public Function GetAddInUI() As INativeHandleContract Implements IWPFAddInContract.GetAddInUI
            ' Convert the FrameworkElement from the add-in to an INativeHandleContract 
            ' that will be passed across the isolation boundary to the host application.
            Dim fe As FrameworkElement = Me.wpfAddInView.GetAddInUI()
            Dim inhc As INativeHandleContract = FrameworkElementAdapters.ViewToContractAdapter(fe)
            Return inhc
        End Function
    End Class
End Namespace

Implementando o segmento de pipeline de exibição de host

Como o aplicativo host exibirá um , o método no modo de exibição do host que se correlaciona a IWPFAddInHostView.GetAddInUI deve retornar um FrameworkElementvalor do tipo FrameworkElement. O código a seguir mostra a exibição do host do contrato, implementada como uma interface.

using System.Windows;

namespace HostViews
{
    /// <summary>
    /// Defines the host's view of the add-in
    /// </summary>
    public interface IWPFAddInHostView
    {
        // The view returns as a class that directly or indirectly derives from
        // FrameworkElement and can subsequently be displayed by the host
        // application by embedding it as content or sub-content of a UI that is
        // implemented by the host application.
        FrameworkElement GetAddInUI();
    }
}

Imports System.Windows

Namespace HostViews
    ''' <summary>
    ''' Defines the host's view of the add-in
    ''' </summary>
    Public Interface IWPFAddInHostView
        ' The view returns as a class that directly or indirectly derives from 
        ' FrameworkElement and can subsequently be displayed by the host 
        ' application by embedding it as content or sub-content of a UI that is 
        ' implemented by the host application.
        Function GetAddInUI() As FrameworkElement
    End Interface
End Namespace

Implementando o segmento de pipeline do adaptador no lado do host

O método contract retorna um , mas o aplicativo host espera um INativeHandleContractFrameworkElement (conforme especificado pela exibição do host). Consequentemente, o deve ser convertido em um FrameworkElement após cruzar o INativeHandleContract limite de isolamento. Esse trabalho é executado pelo adaptador do lado do host chamando ContractToViewAdapter, conforme mostrado no código a seguir.

using System.AddIn.Contract;
using System.AddIn.Pipeline;
using System.Windows;

using Contracts;
using HostViews;

namespace HostSideAdapters
{
    /// <summary>
    /// Adapts the add-in contract to the host's view of the add-in
    /// </summary>
    [HostAdapter]
    public class WPFAddIn_ContractToViewHostSideAdapter : IWPFAddInHostView
    {
        IWPFAddInContract wpfAddInContract;
        ContractHandle wpfAddInContractHandle;

        public WPFAddIn_ContractToViewHostSideAdapter(IWPFAddInContract wpfAddInContract)
        {
            // Adapt the contract (IWPFAddInContract) to the host application's
            // view of the contract (IWPFAddInHostView)
            this.wpfAddInContract = wpfAddInContract;

            // Prevent the reference to the contract from being released while the
            // host application uses the add-in
            this.wpfAddInContractHandle = new ContractHandle(wpfAddInContract);
        }

        public FrameworkElement GetAddInUI()
        {
            // Convert the INativeHandleContract that was passed from the add-in side
            // of the isolation boundary to a FrameworkElement
            INativeHandleContract inhc = this.wpfAddInContract.GetAddInUI();
            FrameworkElement fe = FrameworkElementAdapters.ContractToViewAdapter(inhc);
            return fe;
        }
    }
}

Imports System.AddIn.Contract
Imports System.AddIn.Pipeline
Imports System.Windows

Imports Contracts
Imports HostViews

Namespace HostSideAdapters
    ''' <summary>
    ''' Adapts the add-in contract to the host's view of the add-in
    ''' </summary>
    <HostAdapter>
    Public Class WPFAddIn_ContractToViewHostSideAdapter
        Implements IWPFAddInHostView
        Private wpfAddInContract As IWPFAddInContract
        Private wpfAddInContractHandle As ContractHandle

        Public Sub New(ByVal wpfAddInContract As IWPFAddInContract)
            ' Adapt the contract (IWPFAddInContract) to the host application's
            ' view of the contract (IWPFAddInHostView)
            Me.wpfAddInContract = wpfAddInContract

            ' Prevent the reference to the contract from being released while the
            ' host application uses the add-in
            Me.wpfAddInContractHandle = New ContractHandle(wpfAddInContract)
        End Sub

        Public Function GetAddInUI() As FrameworkElement Implements IWPFAddInHostView.GetAddInUI
            ' Convert the INativeHandleContract that was passed from the add-in side
            ' of the isolation boundary to a FrameworkElement
            Dim inhc As INativeHandleContract = Me.wpfAddInContract.GetAddInUI()
            Dim fe As FrameworkElement = FrameworkElementAdapters.ContractToViewAdapter(inhc)
            Return fe
        End Function
    End Class
End Namespace

Implementando o suplemento

Com o adaptador do lado do suplemento e o modo de exibição de suplemento criados, o suplemento () deve implementar o IWPFAddInView.GetAddInUI método para retornar um FrameworkElement objeto (WPFAddIn1.AddIna UserControl neste exemplo). A implementação do UserControl, AddInUI, é mostrada pelo código a seguir.

    <UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="WPFAddIn1.AddInUI">
    
    <StackPanel>
        <Button Click="clickMeButton_Click" Content="Click Me!" />
    </StackPanel>
    
</UserControl>
using System.Windows;
using System.Windows.Controls;

namespace WPFAddIn1
{
    public partial class AddInUI : UserControl
    {
        public AddInUI()
        {
            InitializeComponent();
        }

        void clickMeButton_Click(object sender, RoutedEventArgs e)
        {
            MessageBox.Show("Hello from WPFAddIn1");
        }
    }
}

Imports System.Windows
Imports System.Windows.Controls

Namespace WPFAddIn1
    Partial Public Class AddInUI
        Inherits UserControl
        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub clickMeButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
            MessageBox.Show("Hello from WPFAddIn1")
        End Sub
    End Class
End Namespace

A implementação do IWPFAddInView.GetAddInUI pelo suplemento simplesmente precisa retornar uma nova instância do AddInUI, conforme mostrado pelo código a seguir.

using System.AddIn;
using System.Windows;

using AddInViews;

namespace WPFAddIn1
{
    /// <summary>
    /// Add-In implementation
    /// </summary>
    [AddIn("WPF Add-In 1")]
    public class WPFAddIn : IWPFAddInView
    {
        public FrameworkElement GetAddInUI()
        {
            // Return add-in UI
            return new AddInUI();
        }
    }
}

Imports System.AddIn
Imports System.Windows

Imports AddInViews

Namespace WPFAddIn1
    ''' <summary>
    ''' Add-In implementation
    ''' </summary>
    <AddIn("WPF Add-In 1")>
    Public Class WPFAddIn
        Implements IWPFAddInView
        Public Function GetAddInUI() As FrameworkElement Implements IWPFAddInView.GetAddInUI
            ' Return add-in UI
            Return New AddInUI()
        End Function
    End Class
End Namespace

Implementando o aplicativo host

Com o adaptador do lado do host e a exibição de host criados, o aplicativo host pode usar o modelo de suplemento do .NET Framework para abrir o pipeline, adquirir uma exibição de host do suplemento e chamar o IWPFAddInHostView.GetAddInUI método. Essas etapas são mostradas no código a seguir.

// Get add-in pipeline folder (the folder in which this application was launched from)
string appPath = Environment.CurrentDirectory;

// Rebuild visual add-in pipeline
string[] warnings = AddInStore.Rebuild(appPath);
if (warnings.Length > 0)
{
    string msg = "Could not rebuild pipeline:";
    foreach (string warning in warnings) msg += "\n" + warning;
    MessageBox.Show(msg);
    return;
}

// Activate add-in with Internet zone security isolation
Collection<AddInToken> addInTokens = AddInStore.FindAddIns(typeof(IWPFAddInHostView), appPath);
AddInToken wpfAddInToken = addInTokens[0];
this.wpfAddInHostView = wpfAddInToken.Activate<IWPFAddInHostView>(AddInSecurityLevel.Internet);

// Get and display add-in UI
FrameworkElement addInUI = this.wpfAddInHostView.GetAddInUI();
this.addInUIHostGrid.Children.Add(addInUI);
' Get add-in pipeline folder (the folder in which this application was launched from)
Dim appPath As String = Environment.CurrentDirectory

' Rebuild visual add-in pipeline
Dim warnings() As String = AddInStore.Rebuild(appPath)
If warnings.Length > 0 Then
    Dim msg As String = "Could not rebuild pipeline:"
    For Each warning As String In warnings
        msg &= vbLf & warning
    Next warning
    MessageBox.Show(msg)
    Return
End If

' Activate add-in with Internet zone security isolation
Dim addInTokens As Collection(Of AddInToken) = AddInStore.FindAddIns(GetType(IWPFAddInHostView), appPath)
Dim wpfAddInToken As AddInToken = addInTokens(0)
Me.wpfAddInHostView = wpfAddInToken.Activate(Of IWPFAddInHostView)(AddInSecurityLevel.Internet)

' Get and display add-in UI
Dim addInUI As FrameworkElement = Me.wpfAddInHostView.GetAddInUI()
Me.addInUIHostGrid.Children.Add(addInUI)

Confira também