preview


Description:

public virtual signal bool preview (PrintOperationPreview preview, PrintContext context, Window? parent)

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 [ method@Gtk.PrintContext.set_cairo_context].

The custom preview implementation can use [method@Gtk.PrintOperationPreview.is_selected] and [method@Gtk.PrintOperationPreview.render_page] to find pages which are selected for print and render them. The preview must be finished by calling [method@Gtk.PrintOperationPreview.end_preview] (typically in response to the user clicking a close button).

Parameters:

preview

the `GtkPrintOperationPreview` for the current operation

context

the `GtkPrintContext` that will be used

parent

the `GtkWindow` to use as window parent

Returns:

true if the listener wants to take over control of the preview