How to...

See the Delphi 10 and Delphi 7 examples on GitHub which demonstrate various io.Connect Desktop features.

The io.Connect COM library allows you to interop-enable your Delphi apps, integrate them with other interop-enabled apps in io.Connect Desktop and use io.Connect functionality in them. To access io.Connect functionalities in your Delphi app, you have to reference and initialize the io.Connect COM library. Currently, the io.Connect COM library supports Delphi 7 and Delphi 10.

Referencing

The io.Connect COM library is available as a package in NuGet which you can include in your projects. The io.Connect COM library is also distributed with io.Connect Desktop and is usually located in the %LocalAppData%/interop.io/io.Connect Desktop/SDK/GlueCOMv2 folder.

To use any io.Connect Desktop functionality, you need to add the following units to your Delphi project:

• GlueCOM_TLB.pas - declarations for the io.Connect COM type library;
• mscorlib_TLB.pas - declarations for the Microsoft Common Object Runtime library (the io.Connect COM type library depends on it);
• GlueHelper.pas - Delphi native types for wrapping low-level COM functionality;

⚠️ Note that you must not import the io.Connect COM type library (GlueCOM.dll) directly into your project. The provided GlueCOM_TLB unit has been modified to use specific alignment for some records. Importing the io.Connect COM type library will overwrite these required modifications.

Initialization

Initialize the io.Connect interface in the app main form by following these steps:

1. Import the GlueCOM_TLB unit:

uses
  GlueCOM_TLB;

2. Declare a variable to hold the io.Connect COM object and a procedure to perform the initialization:

type
  TMainForm = class(TForm)

  private
    // The io.Connect entry point handle.
    G42: IGlue42;
  protected
    procedure InitializeGlue;

3. Implement the initialization:

procedure TMainForm.InitializeGlue;
var
  inst: GlueInstance;
  cfg: GlueConfiguration;
begin
  try
    // Create the io.Connect COM object.
    G42 := CoGlue42.Create() as IGlue42;

    // Configure own identity.
    ZeroMemory(@inst, sizeof(inst));
    inst.ApplicationName := 'MyDelphiApp';
    inst.Metadata := nil;
    ZeroMemory(@cfg, sizeof(cfg));
    cfg.AppDefinitionTitle := 'My Delphi App';
    G42.OverrideConfiguration(cfg);

    // Initialize and start io.Connect.
    G42.Start(inst);
  except
    on E: Exception do
    begin
      // Handle errors.
    end;
  end;
end;

4. You can invoke InitializeGlue in the OnCreate event handler and perform cleanup in the OnClose event handler for the form:

procedure TMainForm.FormCreate(Sender: TObject);
begin
  InitializeGlue;
end;

procedure TMainForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  if Assigned(G42) then
  begin
    G42.Stop;
  end;
end;

To add your Delphi app to the io.Connect launcher, you must create a JSON file with app definition. Place this file in the %LocalAppData%/interop.io/io.Connect Desktop/UserData/<ENV>-<REG>/apps folder, where <ENV>-<REG> represents the environment and region of io.Connect Desktop (e.g., DEMO-INTEROP.IO).

The following is an example definition of a Delphi app:

{
    "title": "My Delphi App",
    "type": "exe",
    "name": "my-delphi-app",
    "details": {
        "path": "%GDDIR%/../Demos/DelphiDemo/",
        "command": "MyDelphiApp.exe",
        "parameters": " --mode=1"
    }
}

The "name", "type" and "path" properties are required and "type" must be set to "exe". The "path" property points to the app working directory.

The value of the "title" property will be used as a name for the app in the io.Connect launcher and as a window title.

For more details, see the Developers > Configuration > Application section.

Once the io.Connect COM library has been initialized, your app has access to all io.Connect functionalities. For more detailed information on the different io.Connect capabilities and APIs, see:

• App Management
• Shared Contexts
• Channels
• Interop
• Window Management

The following sections explain concepts related to using the io.Connect COM library.

io.Connect Time

io.Connect time is essentially a Unix timestamp: the number of milliseconds since the Unix epoch, i.e. 1970-01-01 00:00:00 UTC, ignoring leap seconds.

io.Connect timestamp arguments and values are stored in an Int64 type. To convert from io.Connect time to Delphi TDateTime and vice versa, use the following functions defined in the GlueHelper unit:

function GlueTimeToDateTime(msecs: Int64): TDateTime;
function DateTimeToGlueTime(dt: TDateTime): Int64;

⚠️ Note that io.Connect uses UTC internally, so the resulting TDateTime timestamp will also be in UTC, and not in local time.

The GlueHelper unit contains native type definitions and additional helper classes and methods facilitating the use of the io.Connect COM library.

It is recommended to use the conversion functions provided in the GlueHelper unit to transform the arguments or return values from a PSafeArray to native types and vice-versa:

• The functions in the Create[type]_SA format can be used to transform various native types to a PSafeArray. The returned values need to be destroyed with SafeArrayDestroy when no longer needed.

• The functions in the SA_As[type] format can be used to transform a PSafeArray to various native types.

Types

Array Types

The following array types are defined in the GlueHelper unit:

Pointer Types

The following pointer types are defined in the GlueHelper unit:

Native Record Types

TGlueContextValue

This is a translated version (i.e. not using PSafeArray directly or indirectly) of GlueContextValue representing a name-value pair.

Properties

TGlueValue

This is a translated version (i.e. not using PSafeArray directly or indirectly) of GlueValue representing an elementary or composite value.

Properties

The following properties will be initialized according to GlueType and IsArray:

Working with PSafeArray

The GlueHelper unit provides a set of functions for converting from/to PSafeArray which is widely used when sending or receiving data from io.Connect.

Summary

The table below summarizes the available functions to convert from/to PSafeArray based on the content type.

Conversion Functions

All conversion functions accept a single argument of the respective type. The returned PSafeArray must be destroyed with SafeArrayDestroy when no longer needed.

| Function | Argument Type | Return Type | Array of Type | |----------|----------------|-------------|------------ ---| | AsGlueContextValueArray | TGlueContextValueArray | GlueContextValueArray | GlueContextValue | | CreateArray_SA | TDoubleArray | PSafeArray | Double | | CreateArray_SA | TInt64Array | PSafeArray | Int64 | | CreateArray_SA | TStrArray | PSafeArray | String | | CreateArray_SA | TWideStringArray | PSafeArray | WideString | | CreateArray_SA | TWordBoolArray | PSafeArray | WordBool | | CreateContextValues_SA | GlueContextValueArray | PSafeArray | GlueContextValue | | CreateTuple_SA | GlueValueArray | PSafeArray | GlueValue | | SA_AsDateTimeArray | PSafeArray | TDateTimeArray | TDateTime | | SA_AsDoubleArray | PSafeArray | TDoubleArray | Double | | SA_AsGlueContextArray | PSafeArray | GlueContextArray | GlueContext | | SA_AsGlueContextValueArray | PSafeArray | GlueContextValueArray | GlueContextValue | | SA_AsGlueInstanceArray | PSafeArray | TGlueInstanceArray | GlueInstance | | SA_AsGlueInvocationResultArray | PSafeArray | TGlueInvocationResultArray | GlueInvocationResult | | SA_AsGlueMethodArray | PSafeArray | TGlueMethodArray | GlueMethod | | SA_AsGlueStreamSubscriberArray | PSafeArray | GlueStreamSubscriberArray | IGlueStreamSubscriber | | SA_AsGlueValueArray | PSafeArray | GlueValueArray | GlueValue | | SA_AsInt64Array | PSafeArray | TInt64Array | Int64 | | SA_AsStringArray | PSafeArray | TStrArray | String | | SA_AsTranslatedContextValues | PSafeArray | TGlueContextValueArray | TGlueContextValue | | SA_AsWideStringArray | PSafeArray | TWideStringArray | WideString | | SA_AsWordBoolArray | PSafeArray | TWordBoolArray | WordBool |

Functions for Creating io.Connect and Context Values

CreateContextValue

This function creates a TGlueContextValue representing a name-value pair. It can be put in a TGlueContextValueArray and eventually be converted to a PSafeArray in order to be sent to io.Connect.

Parameters:

Return value: TGlueContextValue

CreateValue

This is a set of overloaded functions for creating TGlueValue values from various types. The overloads accepting arrays will create composite values. Each function accepts the following types as a single argument:

• Double
• Int64
• Integer
• String
• TDoubleArray
• TInt64Array
• TStrArray

Return value: TGlueValue

CreateComposite

This function creates a composite value from a TGlueContextValueArray.

Parameters:

Return value: TGlueValue

CreateTuple

This function creates a composite value representing a tuple, i.e. an array of (possibly) heterogeneous elements.

Parameters:

Return value: TGlueValue

Classes for Handling Events

A set of classes that implement callback interfaces in order to simplify the implementation of callback event handlers.

TGlueRequestHandler

This class implements the IGlueRequestHandler interface which invokes a callback whenever an already registered Interop method is invoked.

Class constructor parameters:

Callback procedure signature:

TRequestHandlerLambda = procedure(Sender: TGlueRequestHandler;
    Method: GlueMethod;
    Instance: GlueInstance;
    Args: GlueContextValueArray;
    callback: IGlueServerMethodResultCallback;
    Cookie: TCallbackCookie;
    argsSA: PSafeArray) of object;

TGlueResultHandler

This class implements the IGlueInvocationResultHandler interface which invokes a callback when the result from an Interop method invocation becomes available.

Class constructor parameters:

Callback procedure signature:

TResultHandlerLambda = procedure(Sender: TGlueResultHandler;
    GlueResult: TGlueInvocationResultArray;
    Cookie: TCallbackCookie;
    const correlationId: WideString) of object;

TGlueStreamHandler

This class implements the IGlueStreamHandler interface which invokes callbacks for events related to Interop streaming methods.

Class constructor parameters:

Callback procedure signature:

TStreamDataLambda = procedure(Method: GlueMethod;
    data: GlueContextValueArray;
    dataAsSA: PSafeArray) of object;

This reference describes the components in the io.Connect COM library relevant to Delphi.

⚠️ Note that the library also contains components that aren't intended to be directly used by Delphi apps.

GlueInstanceIdentity

GlueMethodFlags

GlueMethodInvocationStatus

GlueState

GlueStreamState

GlueValueType

GlueWindowEventType

⚠️ Note that some event types aren't applicable to Delphi apps.

GlueAppDefinition

Definition of a child app to be registered in io.Connect.

Properties

GlueConfiguration

Used for overriding the default io.Connect configuration.

See also:

• IGlue42 - the OverrideConfiguration method.

Properties

GlueContext

Stores information about an io.Connect shared context.

Properties

GlueContextValue

This type represents a name-value pair.

Properties

GlueInstance

Describes the identity of an io.Connect instance, i.e. how the instance is seen by other io.Connect peers.

Properties

GlueInvocationResult

Holds information about the invoked Interop method and the result it has returned.

Properties

GlueMethod

Describes an Interop method.

Properties

GlueResult

Holds information about the result from invoking an Interop method.

Properties

GlueValue

Represents an elementary or composite value.

Properties

The following properties will be initialized according to GlueType and IsArray:

IAppAnnouncer

An instance of this is passed to the implementation of the CreateApp method of the IAppFactory interface.

Methods

AnnounceAppCreationFailure

Informs io.Connect that a new child app instance couldn't be created.

Parameters:

Return value: None

RegisterAppInstance

Registers a new child app instance in io.Connect.

Parameters:

Return value: IGlueWindow

IAppFactory

Implementing this interface allows an object to act as a child app factory.

See also:

• IAppFactoryRegistry - the RegisterAppFactory method.

Methods

CreateApp

Creates a new instance of a child app.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IAppFactoryRegistry

This interface is used for registering app factories and app instances.

Methods

RegisterAppFactory

Registers an app factory as a creator of a child app with the provided definition.

Parameters:

Return value: None

RegisterAppInstance

Register an app instance in io.Connect.

Parameters:

Return value: None

IGlue42

Create a single object of this class in order to access io.Connect functionality.

Properties

Methods

BuildAndInvoke

Invokes an Interop method on a single or multiple targets.

Parameters:

Return value: None

BuildGlueContextValues

Creates a PSafeArray of GlueContextValue values using a callback method.

Parameters:

Return value: PSafeArray

An array of GlueContextValue values. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetAllInstances

Gets an array of all available io.Connect instances.

Parameters: None

Return value: PSafeArray

An array of GlueInstance objects. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetAllMethods

Gets an array of the available Interop methods from all io.Connect instances, including Interop streaming methods.

Parameters: None

Return value: PSafeArray

An array of GlueMethod objects. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetChannels

Gets an array of the names of all available io.Connect Channels.

Parameters: None

Return value: PSafeArray

An array of WideString values with the Channel names. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetInstance

Gets the current io.Connect instance.

Parameters: None

Return value: GlueInstance

Contains information about the current io.Connect app instance.

GetKnownContexts

Gets an array of all available io.Connect shared contexts.

Parameters: None

Return value: PSafeArray

An array of GlueContext values. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetMethodNamesForTarget

Gets the names of the Interop methods exposed by an app.

Parameters:

Return value: PSafeArray

An array of WideString values with the method names. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetMethodsForInstance

Gets the Interop methods exposed by matching one or more app instances.

Parameters:

Return value: PSafeArray

An array of GlueMethod objects. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetStartingContext

Gets the starting context for the app.

Parameters: None

Return value: GlueValue

A GlueValue containing the starting context for the app.

GetStartupWindowSettings

Gets the default settings for the startup window.

Parameters: None

Return value: IGlueWindowSettings

An object of IGlueWindowSettings containing the default settings for the startup window.

GetTargets

Gets the names of all active apps (targets) currently offering Interop methods.

Parameters: None

Return value: PSafeArray

An array of WideString values with the app names. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

InvokeMethod

Invokes an Interop method on a specific single target.

Parameters:

Return value: None

InvokeMethods

Invokes an Interop method on a single or multiple targets.

Parameters:

Return value: None

InvokeSync

Invokes an Interop method synchronously.

Parameters:

Return value: WideString

The string represents the return values from the method invocation in JSON format.

IsLaunchedByGD

Determines whether the app was started by io.Connect Desktop or as a standalone executable.

Parameters: None

Return value: WordBool

The string represents the return values from the method invocation in JSON format.

JsonToVariant

Converts a JSON string to a variant array.

Parameters:

Return value: PSafeArray

An array of variants. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

Log

Outputs a message to the io.Connect log.

Parameters:

Return value: None

OverrideConfiguration

Overrides the default io.Connect configuration. This method must be invoked before invoking the Start method, otherwise it will have no effect.

Parameters:

Return value: None

RegisterGlueWindow

Initiates the registration of a window as an io.Connect Window and sets the related event handler.

Parameters:

Return value: IGlueWindow

An object representing the registered io.Connect Window.

⚠️ Note that the returned value shouldn't be used to interact with the io.Connect Window until the HandleWindowReady callback method is invoked (i.e. the registration is complete).

RegisterGlueWindowWithSettings

Initiates the registration of a window as an io.Connect Window with specific settings and sets the related event handler.

Parameters:

Return value: IGlueWindow

⚠️ Note that the returned value shouldn't be used to interact with the io.Connect Window until the HandleWindowReady callback method is invoked (i.e. the registration is complete).

RegisterMethod

Registers an Interop method.

Parameters:

Return value: GlueMethod

An object describing the registered Interop method. The return value can be used to unregister the method by using its UnregisterMethod method.

RegisterStartupGlueWindow

Initiates the registration of a window as an io.Connect Window and sets the related event handler. Uses the default startup options, if any.

Parameters:

Return value: IGlueWindow

An object representing the registered io.Connect Window.

⚠️ Note that the returned value shouldn't be used to interact with the io.Connect Window until the HandleWindowReady callback method is invoked (i.e. the registration is complete).

RegisterStartupGlueWindowWithSettings

Initiates the registration of a window as an io.Connect Window with specific settings and sets the related event handler. Uses the default startup options, if any.

Parameters:

Return value: IGlueWindow

⚠️ Note that the returned value shouldn't be used to interact with the io.Connect Window until the HandleWindowReady callback method is invoked (i.e. the registration is complete).

RegisterStream

Registers an Interop stream (streaming method) and sets the related subscription handler.

Parameters:

Return value: GlueMethod

An object describing the registered Interop streaming method. The return value can be used to unregister the streaming method by using its UnregisterMethod method.

SetChannelData

Sets the value of a field in an existing io.Connect Channel.

Parameters:

Return value: None

⚠️ Note that:

• If any of the intermediate objects specified in fieldPath (e.g., object1) or the field itself (field1) don't exist in the JSON tree, they will be automatically created.
• If any of the intermediate objects specified in fieldPath already exist in the JSON tree but aren't objects, the call will fail.
• If the field specified in fieldPath (e.g., field1) already exists in the JSON tree, its value will be replaced. This will work also if the existing field is an object.

SetLogConfigurationPath

Overrides the io.Connect logging configuration path. This method must be invoked before invoking the Start method, otherwise it will have no effect.

See also:

• IGlue42 - the OverrideConfiguration method.

Parameters:

Return value: None

Start

Connects to io.Connect and announces the app instance. The connection to io.Connect is necessary for using any io.Connect functionality.

Parameters:

Return value: None

StartWithAppName

Connects to io.Connect and announces the app instance. The connection to io.Connect is necessary for using any io.Connect functionality.

Parameters:

Return value: None

⚠️ Note that invoking this method is equivalent to invoking the Start method with only the ApplicationName property of the Instance parameter initialized.

Stop

Disconnects from io.Connect, shutting down all communication.

Parameters: None

Return value: None

Subscribe

Subscribes an object of a class implementing the IGlueEvents interface for receiving various notifications from io.Connect.

Parameters:

Return value: None

SubscribeGlueContext

Subscribes to an io.Connect shared context.

Parameters:

Return value: None

SubscribeStream

Subscribes to an Interop stream published by an io.Connect app instance and sets the related stream event handler.

Parameters:

Return value: None

SubscribeStreams

Subscribes to an Interop stream published by one or more io.Connect apps and sets the related stream event handler.

Parameters:

Return value: None

SubscribeStreamsFilterTargets

Subscribes to an Interop stream published by one or more io.Connect apps and sets the related stream event handler. Subscription targets can be filtered by name.

Parameters:

Return value: None

UnregisterMethod

Unregisters an Interop method.

Parameters:

Return value: None

Unsubscribe

Cancels a subscription created with the Subscribe method.

Parameters:

Return value: None

Other Methods

The following methods of IGlue42 exposed in the COM library aren't intended to be used in Delphi:

• AddCorrelationInterest
• CloseResource
• CreateGlueData
• CreateGlueValues
• CreateMethodInvocator
• CreateServerMethod
• CreateServerStream
• CreateStreamConsumer
• G4O_XL_OpenSheet
• GetGlueContext
• InvokeAsync
• InvokeVariantData
• RegisterGlueWindowInSink
• RegisterMethodInSink
• RegisterSingleBranchStream
• RegisterStreamInSink
• RegisterVariantMethodInSink
• RegisterVoidMethodInSink
• SubscribeChannel
• SubscribeStreamInSink
• TranslateVbObject
• YieldCallbackData
• YieldCallbackVariantData

IGlueApp

Implementing this interface allows an object to be registered as an io.Connect app instance.

See also:

• IAppAnnouncer - the RegisterAppInstance method.
• IAppFactoryRegistry - the RegisterAppInstance method.

Methods

Initialize

Initializes a child app.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

SaveState

Saves the app state.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

Shutdown

Shuts down the app when io.Connect shuts down.

Parameters: None

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueContext

This interface is implemented by io.Connect shared context objects.

Methods

BuildAndSetContextData

Sets new (replaces) shared context data using a callback method.

Parameters:

Return value: None

BuildAndUpdateContextData

Updates the shared context data using a callback method.

Parameters:

Return value: None

Close

Unsubscribes from the associated io.Connect shared context.

Parameters: None

Return value: None

GetContextInfo

Gets information about the shared context.

Parameters: None

Return value: GlueContext

GetData

Gets the shared context data.

Parameters: None

Return value: PSafeArray

An array of GlueContextValue values. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetDataAsJson

Retrieves data from the shared context by field path and returns it as JSON encoded data.

Parameters:

Return value: WideString

JSON encoded data that represents the shared context data - e.g., "{parent: {child: {age: 5, name:\"Jay\"}}}".

Remove

Removes an elementary or composite value from the shared context.

Parameters:

Return value: None

SetContextData

Sets new (replaces) shared context data.

Parameters:

Return value: None

SetContextDataOnFieldPath

Sets an array of context values under a context field specified by its path. If parts of the values in the path are missing, empty values will be created for them.

Parameters:

Return value: None

UpdateContextData

Updates the shared context data.

Parameters:

Return value: None

UpdateContextDataJson

Updates the shared context data by field path with JSON encoded data.

Parameters:

Return value: None

Other Methods

The following methods of IGlueContext exposed in the COM library aren't intended to be used in Delphi:

• GetReflectData
• Open
• SetValue

IGlueContextBuilder

An instance of this is passed as an argument to the implementation of the Build method of the IGlueContextBuilderCallback interface.

Methods

AddBool

Adds a Boolean value to the shared context data.

Parameters:

Return value: None

AddBoolArray

Adds an array of Boolean values to the shared context data.

Parameters:

Return value: None

AddComposite

Adds a composite value to the shared context data.

Parameters:

Return value: None

AddContextValue

Adds a value represented as a GlueContextValue to the shared context data.

Parameters:

Return value: None

AddDatetime

Adds a datetime value to the shared context data.

Parameters:

Return value: None

AddDatetimeArray

Adds an array of datetime values to the shared context data.

Parameters:

Return value: None

AddDouble

Adds a double-precision floating-point value to the shared context data.

Parameters:

Return value: None

AddDoubleArray

Adds an array of double-precision floating-point values to the shared context data.

Parameters:

Return value: None

AddGlueValue

Adds a value represented as a GlueValue to the shared context data.

Parameters:

Return value: None

AddInt

Adds an integer value to the shared context data.

Parameters:

Return value: None

AddIntArray

Adds an array of integer values to the shared context data.

Parameters:

Return value: None

AddLong

Adds a long integer value to the shared context data.

Parameters:

Return value: None

AddLongArray

Adds an array of long integer values to the shared context data.

Parameters:

Return value: None

AddString

Add a string value to the shared context data.

Parameters:

Return value: None

AddStringArray

Adds an array of string values to the shared context data.

Parameters:

Return value: None

AddTuple

Adds a tuple of values to the context data.

Parameters:

Return value: None

AddTupleValue

Adds a tuple of values represented as a GlueValue to the shared context data.

Parameters:

Return value: None

BuildComposite

Builds a value using a callback method and adds it to the shared context data.

Parameters:

Return value: None

BuildTuple

Builds a tuple value using a callback method and adds it to the shared context data.

Parameters:

Return value: None

Clear

Clears all shared context data.

Parameters: None

Return value: None

IGlueContextBuilderCallback

An instance of this is passed to the implementations of the methods which use callbacks for building shared context data values (e.g., BuildAndSetContextData or BuildComposite).

Methods

Build

Builds the shared context data.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueContextHandler

Implementing this interface allows an object to receive notifications about changes in a shared context.

See also:

• IGlue42 - the SubscribeGlueContext method.

Methods

HandleContext

Handles the shared context when a subscription is activated via SubscribeGlueContext.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleContextUpdate

Handles updates of the associated shared context.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueContextUpdate

Describes an update of a shared context.

Methods

GetAdded

Gets an array of the values which have been added to the shared context.

Parameters: None

Return value: PSafeArray

An array of GlueContextValue values. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetContext

Gets the shared context which has been updated.

Parameters: None

Return value: IGlueContext

GetRemoved

Gets an array of the names of the properties which have been removed from the shared context.

Parameters: None

Return value: PSafeArray

An array of WideString values. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

GetUpdated

Gets an array of the values which have been updated in the shared context.

Parameters: None

Return value: PSafeArray

An array of GlueContextValue values. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

IGlueEvents

Implementing this interface allows an object to receive notifications about various io.Connect events.

See also:

• IGlue42 - the Subscribe method.

Methods

HandleConnectionStatus

Handles the event when the io.Connect connection status changes.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleGlueContext

Handles the event when a new shared context is created.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleInstanceStatus

Handles the event when an io.Connect app instance appears or disappears.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleMethodStatus

Handles the event when an Interop method is registered or unregistered by an app instance.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleException

Handles the event when an exception is thrown during the operation of io.Connect.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueInvocationResultHandler

Implementing this interface allows an object to handle Interop method invocation results.

See also:

• IGlue42 - the BuildAndInvoke method.
• IGlue42 - the InvokeMethod method.
• IGlue42 - the InvokeMethods method.

Methods

HandleResult

Handles the result from invoking an Interop method.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueRequestHandler

Implementing this interface allows an object to handle Interop method invocation requests.

See also:

• IGlue42 - the RegisterMethod method.

Methods

HandleInvocationRequest

Handles the invocation of a registered Interop method.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueServerMethodResultCallback

An instance of this is passed to the implementation of the HandleInvocationRequest method of the IGlueRequestHandler interface.

Methods

SendResult

Sends the result from invoking an Interop method to the caller app instance.

Parameters:

Return value: None

IGlueServerSubscriptionCallback

An instance of this is passed to the implementation of the HandleSubscriptionRequest method of the IGlueSubscriptionHandler interface.

Methods

Accept

Accepts an Interop stream subscription request.

Parameters:

Return value: IGlueStreamBranch

An instance of IGlueStreamBranch representing the branch on which the subscriber was accepted. If the branch parameter is empty, the default (unnamed) branch for the stream will be returned.

Reject

Rejects an Interop stream subscription request.

Parameters:

Return value: None

IGlueStream

Represents a streaming Interop method.

Methods

CloseBranch

Closes a stream branch, disconnecting all subscribers to the branch and removing the branch from the stream.

Parameters:

Return value: None

CloseStream

Closes a stream, disconnecting all subscribers to the stream on all branches. All branches will be removed from the stream.

Parameters: None

Return value: None

GetBranch

Gets an existing stream branch.

Return value: IGlueStreamBranch

Can be used to perform stream actions specific to the branch.

GetBranchKeys

Get the names of the available stream branches.

Parameters: None

Return value: PSafeArray

An array of WideString values with the names of the available branches. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

Push

Pushes data to the stream.

Parameters:

Return value: None

IGlueStreamBranch

Represents a branch of an Interop stream.

Methods

Close

Closes a stream branch, disconnecting all subscribers to the branch and removing the branch from the stream.

Parameters: None

Return value: None

GetKey

Gets the name of the stream branch.

Parameters: None

Return value: WideString

A string containing the name of the stream branch.

GetStream

Gets the Interop stream to which the branch belongs.

Parameters: None

Return value: IGlueStream

An instance representing the Interop stream to which the branch belongs.

GetSubscribers

Gets all subscribers to the stream branch.

Parameters: None

Return value: PSafeArray

An array of IGlueStreamSubscriber instances representing all current subscribers to the stream branch. The returned value must be destroyed with SafeArrayDestroy when no longer needed.

Push

Pushes data to the stream branch.

Parameters:

Return value: None

IGlueStreamHandler

Implementing this interface allows an object to receive notifications about Interop stream events.

See also:

• IGlue42 - the SubscribeStream method.
• IGlue42 - the SubscribeStreams method.

Methods

HandleStreamData

Handles the data that has been pushed by an Interop stream to the subscriber.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleStreamStatus

Handles changes of the state of the Interop stream subscription (e.g., when the subscription is accepted, rejected, closed).

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

StreamClosed

Handles the event when the Interop stream associated with the subscription has been closed.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

SubscriptionActivated

Handles the event when the subscription request has been dispatched to io.Connect.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueStreamSubscriber

Describes an Interop stream subscriber.

Methods

Close

Disconnects the subscriber from the Interop stream.

Parameters:

Return value: None

GetSubscriberInstance

Gets the io.Connect app instance subscribed to the stream.

Parameters: None

Return value: GlueInstance

Description of the io.Connect app instance subscribed to the stream.

Push

Pushes data to the subscriber.

Parameters:

Return value: None

IGlueStreamSubscription

Describes an Interop stream subscription.

Methods

Close

Disconnects the subscriber from the stream.

Parameters: None

Return value: None

IGlueSubscriptionHandler

Implementing this interface allows an object to handle stream subscription events for a registered Interop stream.

See also:

• IGlue42 - the RegisterStream method.

Methods

HandleSubscriber

Handles the event when a new subscriber to the stream has been accepted.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleSubscriberLost

Handles the event when a subscriber has unsubscribed from the stream. This also includes the cases where subscribers have been forcefully unsubscribed when the Close method has been called for a subscriber, stream or stream branch.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleSubscriptionRequest

Handles the event when an io.Connect app instance requests to subscribe to the stream.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueValueReceiver

An instance of this is passed to the implementation of the SaveState method of the IGlueApp interface.

Methods

SendGlueValue

Sends a GlueValue to be set as an app state.

Parameters:

Return value: None

IGlueWindow

Describes an io.Connect Window.

Methods

Activate

Activates the window.

Parameters: None

Return value: None

GetChannelContext

Gets the current Channel context for the window.

Parameters: None

Return value: IGlueContext

If the window is not currently bound to a Channel, returns Null.

GetChannelSupport

Determines whether the Channel Selector box is visible in the io.Connect Window title bar.

Parameters: None

Return value: WordBool

GetId

Gets the io.Connect Window identifier as a string.

Parameters: None

Return value: WideString

GetTitle

Gets the io.Connect Window title.

Parameters: None

Return value: WideString

IsVisible

Determine whether the io.Connect Window is visible.

Parameters: None

Return value: WordBool

SetChannelSupport

Hides or shows the Channel Selector box in the io.Connect Window title bar.

Parameters:

Return value: None

SetTitle

Sets the io.Connect Window title.

Parameters:

Return value: None

SetVisible

Makes the io.Connect Window visible or invisible.

Parameters:

Return value: None

Unregister

Unregisters the io.Connect Window.

Parameters: None

Return value: None

IGlueWindowEventHandler

Implementing this interface allows an object to receive Channel change or update notifications for a registered io.Connect Window.

See also:

• IGlue42 - the RegisterGlueWindow method.
• IGlue42 - the RegisterGlueWindowWithSettings method.
• IGlue42 - the RegisterStartupGlueWindow method.
• IGlue42 - the RegisterStartupGlueWindowWithSettings method.

Methods

HandleWindowReady

Handles the event when the io.Connect Window registration has completed.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleChannelChanged

Handles the event when the user changes the Channel via the Channel Selector box in the window title bar.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleChannelData

Handles the event when the data in the currently selected Channel has changed or when the user selects a new Channel via the Channel Selector box in the window title bar.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleWindowEvent

Handles additional window events.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

HandleWindowDestroyed

Handles the event when the io.Connect Window is destroyed.

Parameters:

Return value: HResult

⚠️ Note that the implementation must return S_OK.

IGlueWindowSettings

Contains properties representing the settings to use during an io.Connect Window registration.

See also:

• IGlue42 - the RegisterGlueWindowWithSettings method.

Properties

StandardButtons

The StandardButtons property specifies which command buttons will be available in the window title bar. A comma-separated list of the following values may be provided: