Graphics.UI.Gtk.Printing.PrintOperation

High-level Printing API

• Module available since Gtk+ version 2.10

Detail

PrintOperation is the high-level, portable printing API. It looks a bit different than other Gtk+ dialogs such as the FileChooser, since some platforms don't expose enough infrastructure to implement a good print dialog. On such platforms, PrintOperation uses the native print dialog. On platforms which do not provide a native print dialog, Gtk+ uses its own, see PrintUnixDialog.

The typical way to use the high-level printing API is to create a PrintOperation object with printOperationNew when the user selects to print. Then you set some properties on it, e.g. the page size, any PrintSettings from previous print operations, the number of pages, the current page, etc.

Then you start the print operation by calling printOperationRun. It will then show a dialog, let the user select a printer and options. When the user finished the dialog various signals will be emitted on the PrintOperation, the main one being 'draw-page' signal, which you are supposed to catch and render the page on the provided PrintContext using Cairo.

By default PrintOperation uses an external application to do print preview. To implement a custom print preview, an application must connect to the preview signal. The functions printOperationPrintPreviewRenderPage, printOperationPreviewEndPreview and printOperationPreviewIsSelected are useful when implementing a print preview.

Printing support was added in Gtk+ 2.10.

Class Hierarchy

| GObject
| +----PrintOperation

Types

data PrintOperation

Instances

Eq PrintOperation

Ord PrintOperation

GObjectClass PrintOperation

PrintOperationPreviewClass PrintOperation

PrintOperationClass PrintOperation

class GObjectClass o => PrintOperationClass o

Instances

PrintOperationClass PrintOperation

castToPrintOperation :: GObjectClass obj => obj -> PrintOperation

toPrintOperation :: PrintOperationClass o => o -> PrintOperation

data PrintOperationPreview

Instances

Eq PrintOperationPreview

Ord PrintOperationPreview

GObjectClass PrintOperationPreview

PrintOperationPreviewClass PrintOperationPreview

class GObjectClass o => PrintOperationPreviewClass o

Instances

PrintOperationPreviewClass PrintOperationPreview

PrintOperationPreviewClass PrintOperation

castToPrintOperationPreview :: GObjectClass obj => obj -> PrintOperationPreview

toPrintOperationPreview :: PrintOperationPreviewClass o => o -> PrintOperationPreview

Enums

data PrintStatus

The status gives a rough indication of the completion of a running print operation.

Constructors

PrintStatusInitial

PrintStatusPreparing

PrintStatusGeneratingData

PrintStatusSendingData

PrintStatusPending

PrintStatusPendingIssue

PrintStatusPrinting

PrintStatusFinished

PrintStatusFinishedAborted

Instances

Bounded PrintStatus

Enum PrintStatus

Eq PrintStatus

Show PrintStatus

data PrintOperationAction

The action parameter to printOperationRun determines what action the print operation should perform.

Constructors

PrintOperationActionPrintDialog

PrintOperationActionPrint

PrintOperationActionPreview

PrintOperationActionExport

Instances

Bounded PrintOperationAction

Enum PrintOperationAction

Eq PrintOperationAction

Show PrintOperationAction

data PrintOperationResult

A value of this type is returned by printOperationRun.

Constructors

PrintOperationResultError

PrintOperationResultApply

PrintOperationResultCancel

PrintOperationResultInProgress

Instances

Bounded PrintOperationResult

Enum PrintOperationResult

Eq PrintOperationResult

Show PrintOperationResult

data PrintError

Error codes that identify various errors that can occur while using the GTK+ printing support.

Constructors

PrintErrorGeneral

PrintErrorInternalError

PrintErrorNomem

PrintErrorInvalidFile

Instances

Bounded PrintError

Enum PrintError

Eq PrintError

Show PrintError

Constructors

printOperationNew :: IO PrintOperation

Creates a new PrintOperation.

Methods

printOperationSetAllowAsync

Arguments

:: PrintOperationClass self

=> self

-> Bool

allowAsync - True to allow asynchronous operation

-> IO ()

Sets whether the printOperationRun may return before the print operation is completed. Note that some platforms may not allow asynchronous operation.

printOperationGetError :: PrintOperationClass self => self -> IO ()

Call this when the result of a print operation is PrintOperationResultError, either as returned by printOperationRun, or in the done signal handler. The returned GError will contain more details on what went wrong.

printOperationSetJobName

Arguments

:: (PrintOperationClass self, GlibString string)

=> self

-> string

jobName - a string that identifies the print job

-> IO ()

Sets the name of the print job. The name is used to identify the job (e.g. in monitoring applications like eggcups).

If you don't set a job name, Gtk+ picks a default one by numbering successive print jobs.

printOperationSetNPages

Arguments

:: PrintOperationClass self

=> self

-> Int

nPages - the number of pages

-> IO ()

Sets the number of pages in the document.

This must be set to a positive number before the rendering starts. It may be set in a beginPrint signal hander.

Note that the page numbers passed to the requestPageSetup and drawPage signals are 0-based, i.e. if the user chooses to print all pages, the last 'draw-page' signal will be for page nPages - 1.

printOperationGetNPagesToPrint

Arguments

:: PrintOperationClass self

=> self

-> IO Int

returns the number of pages that will be printed

Returns the number of pages that will be printed.

Note that this value is set during print preparation phase (PrintStatusPreparing), so this function should never be called before the data generation phase (PrintStatusGeneratingData). You can connect to the statusChanged signal and call printOperationGetNPagesToPrint when print status is PrintStatusGeneratingData. This is typically used to track the progress of print operation.

• Available since Gtk+ version 2.18

printOperationSetCurrentPage

Arguments

:: PrintOperationClass self

=> self

-> Int

currentPage - the current page, 0-based

-> IO ()

Sets the current page.

If this is called before printOperationRun, the user will be able to select to print only the current page.

Note that this only makes sense for pre-paginated documents.

printOperationSetUseFullPage

Arguments

:: PrintOperationClass self

=> self

-> Bool

fullPage - True to set up the PrintContext for the full page

-> IO ()

If fullPage is True, the transformation for the cairo context obtained from PrintContext puts the origin at the top left corner of the page (which may not be the top left corner of the sheet, depending on page orientation and the number of pages per sheet). Otherwise, the origin is at the top left corner of the imageable area (i.e. inside the margins).

printOperationSetUnit

Arguments

:: PrintOperationClass self

=> self

-> Unit

unit - the unit to use

-> IO ()

Sets up the transformation for the cairo context obtained from PrintContext in such a way that distances are measured in units of unit.

printOperationSetExportFilename

Arguments

:: (PrintOperationClass self, GlibString string)

=> self

-> string

filename - the filename for the exported file

-> IO ()

Sets up the PrintOperation to generate a file instead of showing the print dialog. The indended use of this function is for implementing "Export to PDF" actions. Currently, PDF is the only supported format.

"Print to PDF" support is independent of this and is done by letting the user pick the "Print to PDF" item from the list of printers in the print dialog.

printOperationSetShowProgress

Arguments

:: PrintOperationClass self

=> self

-> Bool

showProgress - True to show a progress dialog

-> IO ()

If showProgress is True, the print operation will show a progress dialog during the print operation.

printOperationSetTrackPrintStatus

Arguments

:: PrintOperationClass self

=> self

-> Bool

trackStatus - True to track status after printing

-> IO ()

If track_status is True, the print operation will try to continue report on the status of the print job in the printer queues and printer. This can allow your application to show things like "out of paper" issues, and when the print job actually reaches the printer.

This function is often implemented using some form of polling, so it should not be enabled unless needed.

printOperationSetCustomTabLabel

Arguments

:: (PrintOperationClass self, GlibString string)

=> self

-> string

label - the label to use, or empty to use the default label

-> IO ()

Sets the label for the tab holding custom widgets.

printOperationRun

Arguments

:: (PrintOperationClass self, WindowClass parent)

=> self

-> PrintOperationAction

action - the action to start

-> parent

parent - Transient parent of the dialog

-> IO PrintOperationResult

returns the result of the print operation. A return value of PrintOperationResultApply indicates that the printing was completed successfully. In this case, it is a good idea to obtain the used print settings with printOperationGetPrintSettings and store them for reuse with the next print operation. A value of PrintOperationResultInProgress means the operation is running asynchronously, and will emit the done signal when done.

Runs the print operation, by first letting the user modify print settings in the print dialog, and then print the document.

Normally that this function does not return until the rendering of all pages is complete. You can connect to the statusChanged signal on op to obtain some information about the progress of the print operation. Furthermore, it may use a recursive mainloop to show the print dialog.

If you call printOperationSetAllowAsync or set the allowAsync property the operation will run asynchronously if this is supported on the platform. The done signal will be emitted with the result of the operation when the it is done (i.e. when the dialog is canceled, or when the print succeeds or fails).

printOperationCancel :: PrintOperationClass self => self -> IO ()

Cancels a running print operation. This function may be called from a beginPrint, paginate or drawPage signal handler to stop the currently running print operation.

printOperationDrawPageFinish :: PrintOperationClass self => self -> IO ()

Signalize that drawing of particular page is complete.

It is called after completion of page drawing (e.g. drawing in another thread). If printOperationSetDeferDrawing was called before, then this function has to be called by application. In another case it is called by the library itself.

• Available since Gtk+ version 2.16

printOperationSetDeferDrawing :: PrintOperationClass self => self -> IO ()

Sets up the PrintOperation to wait for calling of printOperationDrawPageFinish from application. It can be used for drawing page in another thread.

This function must be called in the callback of "draw-page" signal.

• Available since Gtk+ version 2.16

printOperationGetStatus

Arguments

:: PrintOperationClass self

=> self

-> IO PrintStatus

returns the status of the print operation

Returns the status of the print operation. Also see printOperationGetStatusString.

printOperationGetStatusString

Arguments

:: (PrintOperationClass self, GlibString string)

=> self

-> IO string

returns a string representation of the status of the print operation

Returns a string representation of the status of the print operation. The string is translated and suitable for displaying the print status e.g. in a Statusbar.

Use printOperationGetStatus to obtain a status value that is suitable for programmatic use.

printOperationIsFinished

Arguments

:: PrintOperationClass self

=> self

-> IO Bool

returns True, if the print operation is finished.

A convenience function to find out if the print operation is finished, either successfully (PrintStatusFinished) or unsuccessfully (PrintStatusFinishedAborted).

Note: when you enable print status tracking the print operation can be in a non-finished state even after done has been called, as the operation status then tracks the print job status on the printer.

printRunPageSetupDialog

Arguments

:: (WindowClass window, PageSetupClass pageSetup, PrintSettingsClass setting)

=> window

parent transient parent.

-> pageSetup

pageSetup an existing PageSetup.

-> setting

settings a PrintSettings

-> IO PageSetup

returns a new PageSetup

Runs a page setup dialog, letting the user modify the values from pageSetup. If the user cancels the dialog, the returned PageSetup is identical to the passed in pageSetup, otherwise it contains the modifications done in the dialog.

Note that this function may use a recursive mainloop to show the page setup dialog. See printRunPageSetupDialogAsync if this is a problem.

printRunPageSetupDialogAsync

Arguments

:: (WindowClass window, PageSetupClass pageSetup, PrintSettingsClass setting)

=> window

parent transient parent.

-> pageSetup

pageSetup an existing PageSetup.

-> setting

settings a PrintSettings

-> (PageSetup -> IO ())

doneCb a function to call when the user saves the modified page setup

-> IO ()

Runs a page setup dialog, letting the user modify the values from pageSetup.

In contrast to printRunPageSetupDialog, this function returns after showing the page setup dialog on platforms that support this, and calls doneCb from a signal handler for the response signal of the dialog.

printOperationPreviewEndPreview :: PrintOperationPreviewClass self => self -> IO ()

Ends a preview.

This function must be called to finish a custom print preview.

printOperationPreviewIsSelected

Arguments

:: PrintOperationPreviewClass self

=> self

preview a PrintOperationPreview

-> Int

pageNr a page number

-> IO Bool

returns True if the page has been selected for printing

Returns whether the given page is included in the set of pages that have been selected for printing.

printOperationPreviewRenderPage

Arguments

:: PrintOperationPreviewClass self

=> self

preview a PrintOperationPreview

-> Int

pageNr the page to render

-> IO ()

Renders a page to the preview, using the print context that was passed to the "preview" handler together with preview.

A custom iprint preview should use this function in its expose handler to render the currently selected page.

Note that this function requires a suitable cairo context to be associated with the print context.

Attributes

printOperationDefaultPageSetup :: (PrintOperationClass self, PageSetupClass pageSetup) => ReadWriteAttr self PageSetup pageSetup

The PageSetup used by default.

This page setup will be used by printOperationRun, but it can be overridden on a per-page basis by connecting to the requestPageSetup signal.

Since 2.10

printOperationPrintSettings :: (PrintOperationClass self, PrintSettingsClass printSettings) => ReadWriteAttr self PrintSettings printSettings

The PrintSettings used for initializing the dialog.

Setting this property is typically used to re-establish print settings from a previous print operation, see printOperationRun.

Since 2.10

printOperationJobName :: (PrintOperationClass self, GlibString string) => Attr self string

A string used to identify the job (e.g. in monitoring applications like eggcups).

If you don't set a job name, GTK+ picks a default one by numbering successive print jobs.

Default value: ""

Since 2.10

printOperationNPages :: PrintOperationClass self => Attr self Int

The number of pages in the document.

This must be set to a positive number before the rendering starts. It may be set in a beginPrint signal hander.

Note that the page numbers passed to the requestPageSetup and drawPage signals are 0-based, i.e. if the user chooses to print all pages, the last drawPage signal will be for page nPages - 1.

Allowed values: >= GMaxulong

Default value: -1

Since 2.10

printOperationCurrentPage :: PrintOperationClass self => Attr self Int

The current page in the document.

If this is set before printOperationRun, the user will be able to select to print only the current page.

Note that this only makes sense for pre-paginated documents.

Allowed values: >= GMaxulong

Default value: -1

Since 2.10

printOperationUseFullPage :: PrintOperationClass self => Attr self Bool

If True, the transformation for the cairo context obtained from PrintContext puts the origin at the top left corner of the page (which may not be the top left corner of the sheet, depending on page orientation and the number of pages per sheet). Otherwise, the origin is at the top left corner of the imageable area (i.e. inside the margins).

Default value: False

Since 2.10

printOperationTrackPrintStatus :: PrintOperationClass self => Attr self Bool

If True, the print operation will try to continue report on the status of the print job in the printer queues and printer. This can allow your application to show things like "out of paper" issues, and when the print job actually reaches the printer. However, this is often implemented using polling, and should not be enabled unless needed.

Default value: False

Since 2.10

printOperationUnit :: PrintOperationClass self => Attr self Unit

The transformation for the cairo context obtained from PrintContext is set up in such a way that distances are measured in units of unit.

Default value: ''UnitPixel''

Since 2.10

printOperationShowProgress :: PrintOperationClass self => Attr self Bool

Determines whether to show a progress dialog during the print operation.

Default value: False

Since 2.10

printOperationAllowAsync :: PrintOperationClass self => Attr self Bool

Determines whether the print operation may run asynchronously or not.

Some systems don't support asynchronous printing, but those that do will return ''PrintOperationResultInProgress'' as the status, and emit the "done" signal when the operation is actually done.

The Windows port does not support asynchronous operation at all (this is unlikely to change). On other platforms, all actions except for ''PrintOperationActionExport'' support asynchronous operation.

Default value: False

Since 2.10

printOperationExportFilename :: (PrintOperationClass self, GlibString string) => Attr self string

The name of a file to generate instead of showing the print dialog. Currently, PDF is the only supported format.

The intended use of this property is for implementing "Export to PDF" actions.

"Print to PDF" support is independent of this and is done by letting the user pick the "Print to PDF" item from the list of printers in the print dialog.

Default value: Nothing

Since 2.10

printOperationStatus :: PrintOperationClass self => ReadAttr self PrintStatus

The status of the print operation.

Default value: ''PrintStatusInitial''

Since 2.10

printOperationStatusString :: (PrintOperationClass self, GlibString string) => ReadAttr self string

A string representation of the status of the print operation. The string is translated and suitable for displaying the print status e.g. in a Statusbar.

See the printOperationStatus property for a status value that is suitable for programmatic use.

Default value: ""

Since 2.10

printOperationCustomTabLabel :: (PrintOperationClass self, GlibString string) => Attr self string

Used as the label of the tab containing custom widgets. Note that this property may be ignored on some platforms.

If this is Nothing, GTK+ uses a default label.

Default value: Nothing

Since 2.10

printOperationSupportSelection :: PrintOperationClass self => Attr self Bool

If True, the print operation will support print of selection. This allows the print dialog to show a Selection button.

Default value: False

Since 2.18

printOperationHasSelection :: PrintOperationClass self => Attr self Bool

Determines whether there is a selection in your application. This can allow your application to print the selection. This is typically used to make a Selection button sensitive.

Default value: False

Since 2.18

printOperationEmbedPageSetup :: PrintOperationClass self => Attr self Bool

If True, page size combo box and orientation combo box are embedded into page setup page.

Default value: False

Since 2.18

printOperationNPagesToPrint :: PrintOperationClass self => ReadAttr self Int

The number of pages that will be printed.

Note that this value is set during print preparation phase (''PrintStatusPreparing''), so this value should never be get before the data generation phase (''PrintStatusGeneratingData''). You can connect to the statusChanged signal and call printOperationGetNPagesToPrint when print status is ''PrintStatusGeneratingData''. This is typically used to track the progress of print operation.

Allowed values: >= GMaxulong

Default value: -1

Since 2.18

Signals

printOptDone :: PrintOperationClass self => Signal self (PrintOperationResult -> IO ())

Emitted when the print operation run has finished doing everything required for printing.

result gives you information about what happened during the run. If result is PrintOperationResultError then you can call printOperationGetError for more information.

If you enabled print status tracking then printOperationIsFinished may still return False after done was emitted.

printOptBeginPrint :: PrintOperationClass self => Signal self (PrintContext -> IO ())

Emitted after the user has finished changing print settings in the dialog, before the actual rendering starts.

A typical use for 'begin-print' is to use the parameters from the PrintContext and paginate the document accordingly, and then set the number of pages with printOperationSetNPages.

printOptPaginate :: PrintOperationClass self => Signal self (PrintContext -> IO Bool)

Emitted after the beginPrint signal, but before the actual rendering starts. It keeps getting emitted until a connected signal handler returns True.

The paginate signal is intended to be used for paginating a document in small chunks, to avoid blocking the user interface for a long time. The signal handler should update the number of pages using printOperationSetNPages, and return True if the document has been completely paginated.

If you don't need to do pagination in chunks, you can simply do it all in the 'begin-print handler', and set the number of pages from there.

printOptRequestPageSetup :: PrintOperationClass self => Signal self (PrintContext -> Int -> PageSetup -> IO ())

Emitted once for every page that is printed, to give the application a chance to modify the page setup. Any changes done to setup will be in force only for printing this page.

printOptDrawPage :: PrintOperationClass self => Signal self (PrintContext -> Int -> IO ())

Emitted for every page that is printed. The signal handler must render the pageNr's page onto the cairo context obtained from context using printContextGetCairoContext.

Use printOperationSetUseFullPage and printOperationSetUnit before starting the print operation to set up the transformation of the cairo context according to your needs.

printOptEndPrint :: PrintOperationClass self => Signal self (PrintContext -> IO ())

Emitted after all pages have been rendered. A handler for this signal can clean up any resources that have been allocated in the beginPrint handler.

printOptStatusChanged :: PrintOperationClass self => Signal self (IO ())

Emitted at between the various phases of the print operation. See PrintStatus for the phases that are being discriminated. Use printOperationGetStatus to find out the current status.

printOptCreateCustomWidget :: PrintOperationClass self => Signal self (IO Widget)

Emitted when displaying the print dialog. If you return a widget in a handler for this signal it will be added to a custom tab in the print dialog. You typically return a container widget with multiple widgets in it.

The print dialog owns the returned widget, and its lifetime is not controlled by the application. However, the widget is guaranteed to stay around until the customWidgetApply signal is emitted on the operation. Then you can read out any information you need from the widgets.

printOptUpdateCustomWidget :: PrintOperationClass self => Signal self (Widget -> PageSetup -> PrintSettings -> IO ())

Emitted after change of selected printer. The actual page setup and print settings are passed to the custom widget, which can actualize itself according to this change.

• Available since Gtk+ version 2.18

printOptCustomWidgetApply :: PrintOperationClass self => Signal self (Widget -> IO ())

Emitted right before beginPrint if you added a custom widget in the createCustomWidtet handler. When you get this signal you should read the information from the custom widgets, as the widgets are not guaraneed to be around at a later time.

printOptPreview :: PrintOperationClass self => Signal self (PrintOperationPreview -> PrintContext -> Window -> IO Bool)

Gets emitted when a preview is requested from the native dialog.

The default handler for this signal uses an external viewer application to preview.

To implement a custom print preview, an application must return True from its handler for this signal. In order to use the provided context for the preview implementation, it must be given a suitable cairo context with printContextSetCairoContext.

The custom preview implementation can use printOperationPreviewIsSelected and printOperationPreviewRenderPage to find pages which are selected for print and render them. The preview must be finished by calling printOperationPreviewEndPreview (typically in response to the user clicking a close button).

printOptReady :: PrintOperationPreviewClass self => Signal self (PrintContext -> IO ())

The ready signal gets emitted once per preview operation, before the first page is rendered.

A handler for this signal can be used for setup tasks.

printOptGotPageSize :: PrintOperationPreviewClass self => Signal self (PrintContext -> PageSetup -> IO ())

The gotPageSize signal is emitted once for each page that gets rendered to the preview.

A handler for this signal should update the context according to pageSetup and set up a suitable cairo context, using printContextSetCairoContext.