FileChooser.connectUpdatePreview
gulong connectUpdatePreview(T)(T callback, Flag!"After" after = No.After)Connect to UpdatePreview signal.
This signal is emitted when the preview in a file chooser should be regenerated. For example, this can happen when the currently selected file changes. You should use this signal if you want your file chooser to have a preview widget.
Once you have installed a preview widget with gtk.file_chooser.FileChooser.setPreviewWidget, you should update it when this signal is emitted. You can use the functions gtk.file_chooser.FileChooser.getPreviewFilename or gtk.file_chooser.FileChooser.getPreviewUri to get the name of the file to preview. Your widget may not be able to preview all kinds of files; your callback must call gtk.file_chooser.FileChooser.setPreviewWidgetActive to inform the file chooser about whether the preview was generated successfully or not.
Please see the example code in Using a Preview Widget.
See also: gtk.file_chooser.FileChooser.setPreviewWidget, gtk.file_chooser.FileChooser.setPreviewWidgetActive, gtk.file_chooser.FileChooser.setUsePreviewLabel, gtk.file_chooser.FileChooser.getPreviewFilename, gtk.file_chooser.FileChooser.getPreviewUri.
Parameters
callback | signal callback delegate or function to connect void callback(gtk.file_chooser.FileChooser fileChooser) fileChooser the instance the signal is connected to (optional) |
after | Yes.After to execute callback after default handler, No.After to execute before (default) |