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Miraplacid Text Driver SDK 2007: Programming

 

Miraplacid Text Driver SDK Programming Guide


Miraplacid Text Driver SDK Programming Manual


Contents


Miraplacid Text Driver is actually a collection of ActiveX objects which communicate with each other trough well-defined COM interfaces. This model allows us to keep the system highly scalabe and extensible. Every component could be developed independently and base on different technologies as long as it supports COM. All examples provided in this guide are written in VB 6.0 for simplicity.
There are 5 different types of software modules in Text Driver:
  • Driver components. These are system dll modules and settings files. This is mandatory part of Text Driver.
  • Core component (mtd_core.exe). This is the heart of the whole system. It takes data from the driver, keeps it in internal queue and manages all other components - plug-ins and UI.
  • UI (mtd_ui.exe). This is User Interface component. This is COM client of Core component; it uses Core methods and receives COM events from Core. UI interacts with Core only; it have no direct access to other components. User Interface module is not required for Text Driver Core and Driver, they can work fine without UI. To display transport and rendering plug-ins user interfaces, UI loads its own set of plug-ins as an ActiveX components.
  • Rendering plug-ins. Inproc dll ActiveX modules which performs text rendering (reconstruction) from internal representation into particular text format. Core component manages these modules.
  • Transport plug-ins. Inproc dll ActiveX modules which allows to save resulting files to some locations. Core component manages these modules.
This manual describes only Core and UI interaction details and registration services.
Transport and Rendering plug-ins interfaces are still subject of change and will be presented in the next version os SDK.

For simple solutions like scripting support or object creation from VB, please, refer to Scripting manual.

Miraplacid Text Driver Object Model


Text Driver Core component consists of two COM objects (coclasses):
  • coclass MTD (MiraplacidSE.TextDriver {B2A1B097-BA0F-45d5-918E-E3585D214DB5}). This is the main part of Text Driver.
    The folowing interfaces included:
    • IMTD (default interface). Includes all methods and properties which control Text Driver functionality, including plug-ins.
    • _IMTDEvents (default, source interface). This interface is collection of COM events and provided for Core and UI interoperability.
    • Some other internal interfaces which are out of scope of current document. You do not have to learn them to build your system.
  • coclass MTD_Register (MiraplacidSE.TextDriverRegistrator {106FEB4A-D696-4557-82CB-69BCECF76A61}). This objects includes single interface IMTD_Register, which manages registration and verification services.
MTD_Register object will be always created and its interface will allow calling program to verify Text Driver registration status and to register Text Driver. MTD object will not be created successfully if trial period is expired. Unlimited version of SDK does not contain MTD_Register coclass and object MTD will be created always.

For C++ users: Number means long and String means BSTR in this guide.
Do not forget to add get_ (read) and put_ (write) prefixes for properties.

Miraplacid Text Driver IMTD Object Reference


This is a main Text Driver interface. Its IID is {D5FD471D-BAEC-4dfa-8C3C-CCD09050B3AA}.

Property Type Description
Format String (Read / Write) Selects format plug-in ("Output Style"). PLug-ins should be named by their internal (short) names.
The following values are valid:
Formatted - "Formatted Text"
TWL - "Text with Layout"
XML - "XML"
RSS - "RSS"
Plain - "Plain Text"
FormatParam VARIANT(String PluginName, String ParameterName) (Read / Write) Format Plug-in Parameters. All the parameters for all plug-ins are listed below.
FormatPluginNames String Collection (Read Only) List of installed format plug-ins (XML, Plain Text and so on)
Transport String (Read / Write) Selected Transport Plug-in names. If more than one transport plug-in selected, names should be comma delimited.
The following values are valid: Clipboard, FTP, File, HTTP. Mail, Printer.
TransportParam VARIANT(String PluginName, String ParameterName) (Read / Write) Transport Plug-in Parameters All the parameters for all plug-ins are listed below.
TransportPluginNames String Collection (Read Only) List of installed transport plug-ins (File, FTP and so on)
Charset Number (Read / Write) Character set (codepage number)
5 - UNICODE
437 - OEM American DOS
850 - OEM Latin-1 DOS
852 - OEM Eastern Europe DOS
866 - OEM Cyrillic DOS
932 - Japanese
936 - Chinese (Simplified")
949 - Korean
950 - Chinese (Traditional)"
1250 - ANSI Latin-1 Windows
1251 - ANSI Cyrillic Windows
1252 - ANSI Eastern Europe Windows
1257 - ANSI Baltic Windows
...etc...
UnixEOL Number (Read / Write) End Of Line style
0 means "Windows" EOL style (\r\n or 0x0D, 0x0A)
1 means "UNIX" EOL style (\n or 0x0A)
AutoSave Number (Read / Write) 0 - interactive mode; 1 - Process and Auto-send to the specified destinations
PageBreak Number (Read / Write) 1 - insert page break symbols (0xc) between pages; 0 - don't.
Pages String Collection (Read only) Collection of text pages extracted
TotalPages Number (Read Only) Total estimated amount of pages in current print job
DocumentName String (Read Only) Original name of the printed document
JobStatus Number (Read Only) 0 - Created, 0001b - Opened, 0010b - Printed, 0100b - RequestedPagePrepared, 1000b - Aborted
Printer String (Read / Write) Name of the currently selected printer
Printers String Collection (Read Only) List of all printers in Text Driver collection.
RedirectPrinter String (Read / Write) Name of the currently selected printer for redirection. If empty, no redirection will be performed.
SystemPrinters String Collection (Read Only) List of all printers installed in the system. Useful for user interface, this property allows UI to avoid using spooler API.
DefaultPrinter String (Read Only) Name of the default printer in the system.
UnicodePrefix Number (Read / Write) 1 - insert Unicode prefix (0xfeff) before Unicode content; 0 - don't.
AutoSaveFromUI (hidden) Number (Write only) 0 - interactive mode; 1 - Process and Auto-save to the specified destinations.
This property is intended for use from UI. Regular property AutoSend causes core to unload UI. AutoSendFromUI does not lead UI unloading.
UILoaded (hidden) Number (Read / Write) 0 - UI not loaded; 1 - UI loaded.
UI should set this value when it loaded and initialized and clear (set to 0) on unload.
Method Parameters Description
UpdatePage Number n, String s Replace contents of nth page by s.
CancelJob None Cancel current Print Job
CancelAllJobs None Cancel all jobs for this printer
SaveConfiguration None Save Configuration for currently selected printer
SaveAllPages None Send All through selected Transport Plug-Ins
Stop None Unloads plug-ins, get ready for unloading from memory. System will unload Miraplacid Text Driver core form memory with 2-5 seconds delay. We recommend you to add this method call at the end of each script.
SavePage (hidden) Number Save one page specified by argument (index)

Miraplacid Text Driver Send To (Transport plug-ins) parameters


To query or modify Transport plug-in parameters, use TransportParam property of Miraplacid Text Driver object.
obj.TransportParam("File","filename")="textout_{{PAGE}}.txt"

File
Property Type Description
path String Destination File Path. {{PAGE}}, {{JOB}}, {{IDENTITY}}, {{DATE}}, {{TIME}} supported.
filename String Destination File Name. {{PAGE}}, {{JOB}}, {{IDENTITY}}, {{DATE}}, {{TIME}} supported.
open Number Opens resulting text file with post-processor.
hide Number 0 = show post-processor window. 1 = hide post-processor window. Ignored if open=0.
exec String Post-processor filename with full path. Ignored if open=0.
param String additional parameters for post-processor. Ignored if open=0.
setfilename Number Set it to 0 if you wish to specify filename. Set it to 1 if you Miraplacid Text Driver to use original document name as a file name. Ignored if open=0.
append Number Set it to 0 if you wish to overwrite resulting file. Set it to 1 if you wish to append current result to a previous file.
docname (hidden, Write only) String This parameter is used by Core component to feed plug-ins with document name to allow them use document name as a filename. Parameter docname provided with file extension got from render plug-in, i.e. "textout.xml".
This parameter has not appropriate entry in Layout property and will not be saved in registry as an item of configuration.
FTP
Property Type Description
url String Destination FTP directory URL.
file String Destination File Name. {{PAGE}}, {{JOB}}, {{IDENTITY}}, {{DATE}}, {{TIME}} supported.
passive Number 0 = FTP passive mode OFF. 1 = FTP passive mode ON.
user String FTP server username.
password String FTP server password.
setfilename Number Set it to 0 if you wish to specify filename. Set it to 1 if you Miraplacid Text Driver to use original document name as a file name. Ignored if open=0.
docname (hidden, Write only) String This parameter is used by Core component to feed plug-ins with document name to allow them use document name as a filename. Parameter docname provided with file extension got from render plug-in, i.e. "textout.xml".
This parameter has not appropriate entry in Layout property and will not be saved in registry as an item of configuration.
HTTP
Property Type Description
url String Destination HTTP URL.
file String Destination File Name.
put Number 0 = use POST method. 1 = use PUT method.
user String username.
password String password.
setfilename Number Set it to 0 if you wish to specify filename. Set it to 1 if you Miraplacid Text Driver to use original document name as a file name. Ignored if open=0.
docname (hidden, Write only) String This parameter is used by Core component to feed plug-ins with document name to allow them use document name as a filename. Parameter docname provided with file extension got from render plug-in, i.e. "textout.xml".
This parameter has not appropriate entry in Layout property and will not be saved in registry as an item of configuration.
Printer
Property Type Description
printer String Printer name. Can be a real printer name or "Default" string which means default printer.
font String Font family name to use in print output or "Default" string to not to use any specific font when printing.
charset Number Numeric code of character set or DEFAULT_CHARSET value (equal to 1).
weight Number Weight of characters to be used in print output.
The following values will be accepted:

0 - DONTCARE
100 - THIN
200 - EXTRALIGHT
300 - LIGHT
400 - NORMAL
500 - MEDIUM
600 - SEMIBOLD
700 - BOLD
800 - EXTRABOLD
900 - BLACK
height Number Height of characters to be used in print output.
italic Number Specifies an italic font if set to 1.
strikeout Number Specifies an strikeout font if set to 1.
underline Number Specifies an underline font if set to 1.
Mail
Property Type Description
mail String A set of email addresses of mail recipients, separated by semicolon.
subject String Email subject.
message String Email message body. This value will be used as a header before actual email content (printed pages).
Text Driver will place this message, separator line, then printed pages.
Clipboard
Property Type Description
open Number Opens resulting text file with post-processor.
hide Number 0 = show post-processor window. 1 = hide post-processor window. Ignored if open=0.
exec String Post-processor filename with full path. Ignored if open=0.
param String additional parameters for post-processor. Ignored if open=0.

Miraplacid Text Driver Formatting Style (Rendering plug-ins) parameters


To query or modify Format plug-in parameters, use FormatParam property of Miraplacid Text Driver object.
obj.FormatParam("TWL","margins")=1

Plain Text
Property Type Description
delim String Delimiter which will be used to separate text boxes during rendering.
Formatted Text, Text with Layout
Property Type Description
margins Number 1 - use printer margins in text rendering (at top and left side); 0 - don't.
XML
Property Type Description
optimize Number 1 - merge textboxes into whole words; 0 - don't.
docname (hidden, Write only) String This parameter is used by Core component to feed plug-ins with document name to allow them use document name as a part of document's body.
This parameter has not appropriate entry in Layout property and will not be saved in registry as an item of configuration.
RSS
Property Type Description
link String Link attribute of RSS channel (document).
description String Description attribute of RSS channel (document).
br Number 1 - add <BR> tag to the end of description lines; 0 - don't.
docname (hidden, Write only) String This parameter is used by Core component to feed plug-ins with document name to allow them use document name as a part of document's body.
This parameter has not appropriate entry in Layout property and will not be saved in registry as an item of configuration.

Miraplacid Text Driver _IMTDEvents Events Reference.


This is connection point interface which UI uses to catch printing events from Core component. Its IID is {95204725-F17E-43c0-A56B-784D7292D28F}.

Event Parameters Description
OnStartJob None Called when Core receives start job signal from driver.
OnPageRendered Number Called when Core receives all text fragments for the current page and rendered it with currently selected Rendering plug-in.
OnAllPagesRendered None Called when Core receives end job signal from driver and rendered all job pages.
OnCancelJob None Called when Core finishes all activity with current job as an acknowledge for CancelJob call from UI or after SendAll process end. The job is removed from MTD.
OnRewindJob None Called instead of OnCancelJob when SendAll finished with errors. The job is not destroyed and still active.
OnUnload None Called when AutoSend property is set to true. UI should unload upon receiving this event.
OnProgress String source, Number value Called when some lengthy process is taking place. Source is a name of transport plug-in - it reflects sending progress for this particular plug-in. Value is the value of progress indicator (0 - 100).
OnError Number code, String message Called when some error is happened. Message is textual representation of the error. There are the folowing codes could be passed to this event:
  • General errors - code = 1
  • If page ID is wrong - code = 0x400
  • Name errors: configuration, unknown transport or format selected - code = 0x600
  • Range 0x100 - 0x1ff has a special meaning - these are transport plug-in errors. Source transport plug-in may be located by its index which is equal to error_code - 0x100; these errors may happen only during saving procedure.
OnSetDocName String docname, String filename Called when Core sets document name to let UI update its set of transport plug-ins with this docname.
UI may use docname to update its status line, etc. Parameter filename should be used to update its own set of transport plug-ins.
OnChangePrinter String Called when Core receives print job for different printer or after initial configuration load. UI must re-read all the configuration from Core.

Miraplacid Text Driver IMTD_Register Object Reference.


When evaluation period is expired, object of the main interface (IMTD) will not be created successfully. Application should use IMTD_Register interface to register Text Driver. Its IID is {F33D6725-86D8-401b-A5B9-9331DCE23125}.
Example of registration utility is located at examples\register folder at this package. It is written in VB.

Property Type Description
Valid Number May be used to examine current evaluation state. Has the following values:
  • <=0 - Internal error happened in verification code. This could be caused by corrupted .key file, wrong permissions of .key file, etc.
  • 1 - Text Driver is registered.
  • 2 - Text Driver is unregistered but trial period is not expired.
  • 3 - Trial periond is expired.
Method Parameters Returns Description
SetLicense String FirtsName, String LastName, String Keycode Number This method is intended for registering Text Driver. Application must provide FirstName, LastName and Keycode generated by Miraplacid to this method. Resulting value is 1 if registration succeeded, 0 if not. After 3 unsuccessful registration attempts this method will always return CLASS_E_NOTLICENSED and will not actually try to register. Application should re-create the object to continue registering.
LoadUI None None Method LoadUI allows application to force loading UI which will ask user for registration information. This could be done if Valid property returns 2 or 3.

Miraplacid Text Driver UI working scheme.


You can see a live custom UI example in examples\customui folder of SDK package.
It is written in VB. Since it is just an example, it does not display pictures and does not let you to change settings and profiles.
  1. UI is launched by Core when it receives a new job and AutoSave property is in false state or by user when he clicks on Text Driver icon on Desktop or Programs folder.
  2. UI loads MTD object and obtains IMTD interface pointer.
  3. UI establishes a connection with Core and loads configuration (by reading properties). After initialization steps (when it will be ready to receive events), UI must set UILoaded property to 1 (true). Core will wait this for 60 seconds; if UI will not register with this property, Core will continue without UI.
Further steps (4 - 6) make an event-driven loop.
  1. OnStartJob: On this event UI may read document name and examine print job status. Job may already be completed (printed) if next job was printed on background before finalizing previous one. Together with this event, Core sends OnChangePrinter (for printer name and configuration update) and OnSetDocName (for transports update).
  2. OnPageRendered: This event will be generated for every page of the job during rendering process even if actual print job was completed. On this event, its possible to get the page with Pages Core property and update UI state.
  3. OnAllPagesPrinted: This is informational event which allows UI to update its internal state (and interface elements like SaveAll button).
The following stage is interactive job with end user.
  1. User can change settings. Appropriate Core properties must be set by UI. During this process, OnError event might be raised in response to incorrect property change.
  2. User can change configurations, create new configurations and delete existing (except Default). When User Interface changes configuration, it shall reload all settings.
  3. User can save current page. UI shall call SendPage method.
  4. User can change current page. UI shall call UpdatePage method with new contents of the page.
  5. User may want to save all pages. UI shall call SendAllPages method. In response to this call, Core will notify UI by raising OnCancelJob event when job is done. On this event, UI must get ready for the next job. If some transports fail, Core raises OnRewindJob event (but does not cancels the job). On this event UI can rewind the job to the first page, show some (additional) error message, etc.
  6. User can cancel the job. UI must call CancelJob method. In response, Core generates OnCancelJob event.
  7. Special case is AutoSend property. UI should call AutoSendFromUI instead of AutoSend property. When AutoSend is set to 1, Core will raise OnUnload event to tell UI that all further processing will be performed automatically and without UI. AutoSendFromUI property does not generate OnUnload event. AutoSend property should be used from scripts to make sure that all processing will be performed as fast as possible and completely in the background. If your UI ignores OnUnload event (does not unload itself), there is no difference between AutoSend and AutopSendFromUI for it.

Miraplacid Text Driver Rendering plug-ins.


Rendering plug-ins are Text Driver components intended for text pages creation from text boxes collected by driver engine.
Rendering plug-ins are AcitveX components which implements all standard visual ActiveX component interfaces.
Additionally, it must obey the following requirements:
  • It must be included into "Miraplacid Text Driver Rendering Plug-ins" COM category (844F0FA2-6FCF-4DDC-8028-EA9B2678D549), but not create it.
  • It must implement IMTD_FPLUGIN interface (769FF02D-AD79-4b0e-9DC7-0CD85C896520) and realize _IMTD_FPlugin_Events connection point dispinterface (79EADD1F-C31C-44ef-8287-267CB278E60B).
  • It must not register its own type library. Ready for use type library provided in imtd_plugin.dll.

IMTD_FPLUGIN interface:

Property Type Description
Value Variant (Read/Write) Any properties that your plug-in may have. Some of them may be saved into configuration in registry and restored from it.
Name String (Read Only) Plug-in name for internal use.
Descirption String (Read Only) Plug-in name use in user interface or so (full name).
Layout String (Read Only) This string contains a list of properties (Values) which should be saved inconfiguration or restored from it.
Format of this string is: "Bparam1,Lparam2,BParam3", where "B" and "L" are prefixes meaning type of parameter (BSTR and Long accordingly). Parameter names should be separated by commas. Spaces are not allowed.
Extension String (Read Only) File extension corresponding current rendering plug-in, without leading period, i.e. "xml", "rss".
Method Parameters Description
StartDoc no parameterts; returns String MTD Core call this member when it performs SaveAll procedure (saves whole document). This will happen after all rendering has completed.
Plug-in should return document header to Core.
If document has no special header, plug-in should return E_NOTIMPL.
EndDoc no parameterts; returns String MTD Core call this member when it performs SaveAll procedure (saves whole document). This method will be called directly after StartDoc.
Plug-in should return document footer to Core.
If document has no special footer, plug-in should return E_NOTIMPL.
StartPage Number DPI, Number Xsize, Number Ysize MTD Core call this member before rendering each page. DPI is page resolution, XSize is X dimension in "dots", Ysize is Y dimension.
Add Number X0, Number X1, Number Y0, Number Y1, String text, String font With this method, MTD Core feeds rendering plug-in with textboxes for rendering. X0, X1, Y0, Y1 are textbox coordinates, "text" is a text itself, "font" is a font name.
Render no parameterts; returns String MTD Core call this member when it finishes adding all textboxes of the page to rendering plug-in.
Plug-in should render the text and return it to Core.

_IMTD_FPlugin_Events interface:

Method Parameters Description
OnChangeParam String plugin, String param, VARIANT val When some plug-in parameter has changed via user interface, plug-in informs about that with OnChangeParam event.
"plugin" is internal name of plug-in, "param" is a name of changed parameter, "val" is a new value of parameter.

Rendering plug-in working scheme

  1. UI starts and loads plug-ins. It subscribes to _IMTD_FPlugin_Events events interface.
  2. UI gets Layout property. According to Layout parameters, it reads appropriate FormatParam properties from Core and sets as a Values of plug-in.
  3. Core creates plug-ins too, but it does not subscribe to events.
  4. Core gets Layout property. According to Layout parameters, it reads saved values from configuration (registry) and sets as Values of plug-in.
Remark: UI and Core may start each other, but the final situation does not change: Core reads settings and sets plug-in properties first, then UI reads these properties and sets them to its "own" plug-ins.
There are two sets of plug-ins exists in the scheme, because UI and Core are separate processes.

Interactive job cycle:
  1. User changes settings of plug-in. Plug-in updates its internal state and raises OnChangeParam to UI.
  2. In responce, UI sets appropriate Core property with FormatParam. In result, all parameters are in sync.
Rendering job cycle. Job of rendering plug-in is page-oriented.
  1. When Core has complete page to render, it calls StartPage method.
  2. After that, it feeds plug-in with all textboxes belonging to this page.
  3. Finally, Core calls Render method and gets rendered text to its storage.
  4. If Core performs SaveAll procedure, after rendering all pages, it calls StartDoc and EndDoc, inserts these pages into its internal storage and save its contents to chosen destinations.

Miraplacid Text Driver Transport plug-ins.


Transport plug-ins are Text Driver components intended saving rendered text pages to some destination (file, URL) using some transport protocol (file, FTP, HTTP).
Transport plug-ins are AcitveX components which implements all standard visual ActiveX component interfaces.
Additionally, it must obey the following requirements:
  • It must be included into "Miraplacid Text Driver Transport Plug-ins" COM category (3B71E527-6CFD-41d3-ABDF-280EF6BB077C), but not create it.
  • It must implement IMTD_TPLUGIN interface (515485DA-9BDB-4552-9D00-FA5C11A9FB6C) and realize _IMTD_TPlugin_Events connection point dispinterface (05EBA977-C40C-47f7-9A9E-6CED35615557).
  • It must not register its own type library. Ready for use type library provided in imtd_tplugin.dll.
  • Default write-only property docname may be used in transport plug-in to capture this setting from UI.

IMTD_TPLUGIN interface:

Property Type Description
Value Variant (Read/Write) Any properties that your plug-in may have. Some of them may be saved into configuration in registry and restored from it.
Name String (Read Only) Plug-in name (short).
Layout String (Read Only) This string contains a list of properties (Values) which should be saved inconfiguration or restored from it.
Format of this string is: "Bparam1,Lparam2,BParam3", where "B" and "L" are prefixes meaning type of parameter (BSTR and Long accordingly). Parameter names should be separated by commas. Spaces are not allowed.
Method Parameters Description
Start None MTD Core call this member when it begins saving text page(s). Plug-in may update its internal state and prepare resources.
Process IRenderedCollection coll, BOOL saveall, Number page_id, Number job_id, Number identity

Returns Number identity_changed
MTD Core calls this method once regardless of number of pages to save. "coll" parameter is an interface provided by Core which allows plug-in to retrieve pages from Core storage.
"saveall" = true - save all pages into destination; otherwise plug-in must use page_id to retrieve particular page.
"page_id", "job_id" and "identity" parameters provided for destination name construction purposes.
If identity was used for name construction, plug-in should return nonzero value to let Core increment identity.
End None MTD Core call this member on end of saving to let plug-in free used resources and update its state.

_IMTD_TPlugin_Events interface:

Method Parameters Description
OnChangeParam String plugin, String param, VARIANT val When some plug-in parameter has changed via user interface, plug-in informs about that with OnChangeParam event.
"plugin" is internal name of plug-in, "param" is a name of changed parameter, "val" is a new value of parameter.
OnError String plugin, Number error_code, String error_message When some error happens during saving the text, plug-in should raise OnError event. "error_code" provided mainly for debugging purposes, to watch this value in MTD log file; "error_message" is what user will see as an error description.
OnProgress String plugin, Number value Plug-in should raise this event periodically during saving process. Value is the value of progress indicator (0 - 100).

IRenderedCollection Core interface:

Property Type Description
Count Number (Read Only) Number of pages in document.
Unicode Number (Read Only) Returns TRUE if the current codepage is Unicode and Unicode prefix option is ON. Plug-ins should use this property before saving all the pages, i.e. should send Unicode prefix (0xfeff) into its output stream before all other content.
Method Parameters Description
Item Number index; returns VARIANT With this method, plug-in receives page content identified by "index". Methods makes all necessary processing with page (end-of-line conversion, translation into needed codepage and page breaks insertion) and provides a result as a VARIANT containing one-dimension SAFEARRAY of bytes.
GetItem Number index; returns String In some cases, plug-in does not need to have processed result. In this case, it should call GetItem method to get just Unicode string of rendered page. Examples of such plug-ins are Clipboard and Printer.
ItemSize Number index; returns Number Some plug-ins need to know page size before sending actual content to destination because transport protocol requires size to be indicated before body; for example, HTTP plug-in. This method returns size of particular page in bytes, taking into account all necessary transformations.

Transport plug-in working scheme

  1. UI starts and loads plug-ins. It subscribes to _IMTD_TPlugin_Events events interface.
  2. UI gets Layout property. According to Layout parameters, it reads appropriate TransportParam properties from Core and sets as a Values of plug-in.
  3. Core creates plug-ins and subscribes to events. UI listens OnParamChange event; Core listens other events: OnError and OnProgress.
  4. Core gets Layout property. According to Layout parameters, it reads saved values from configuration (registry) and sets as Values of plug-in.
Remark: UI and Core may start each other, but the final situation does not change: Core reads settings and sets plug-in properties first, then UI reads these properties and sets them to its "own" plug-ins.
There are two sets of plug-ins exists in the scheme, because UI and Core are separate processes.

Interactive job cycle:
  1. User changes settings of plug-in. Plug-in updates its internal state and raises OnChangeParam to UI.
  2. In responce, UI sets appropriate Core property with TrandportParam. In result, all parameters are in sync.
Saving job cycle.
  1. In response to Save or SaveAll method call, Core initiates saving procedure. Several plug-ins may work at the same time.
    Care calls Start method of each plug-in.
  2. After that, it calls Process method with appropriate parameters.
  3. Finally, Core calls End method.

See also:

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