webkit-0.14.2.0: Binding to the Webkit library.

Maintainergtk2hs-users@lists.sourceforge.net
Stabilityprovisional
Portabilityportable (depends on GHC)
Safe HaskellNone
LanguageHaskell98

Graphics.UI.Gtk.WebKit.WebView

Contents

Description

Note:

Signal `window-object-cleared` can't be bound now, because it needs JavaScriptCore that hasn't binding.

Signal `create-plugin-widget` can't be bound now, no idea how to bind GHaskellTable

  • TODO:

Binding for webkit_web_view_get_snapshot

Synopsis

Description

Cf http:

Types

Enums

Constructors

webViewNew :: IO WebView Source #

Create a new WebView widget.

It is a Widget you can embed in a ScrolledWindow.

You can load any URI into the WebView or any kind of data string.

Methods

Load

webViewLoadUri :: (WebViewClass self, GlibString string) => self -> string -> IO () Source #

Requests loading of the specified URI string in a WebView

webViewLoadHtmlString Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> string

content - the html string

-> string

base_uri - the base URI

-> IO () 

Loading the content string as html. The URI passed in base_uri has to be an absolute URI. Deprecated since webkit v1.1.1, use webViewLoadString instead.

webViewLoadRequest :: (WebViewClass self, NetworkRequestClass request) => self -> request -> IO () Source #

Requests loading of the specified asynchronous client request. Creates a provisional data source that will transition to a committed data source once any data has been received. Use webViewStopLoading to stop the load.

webViewLoadString Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> string

content - the content string to be loaded.

-> Maybe string

mime_type - the MIME type or Nothing.

-> string

base_uri - the base URI for relative locations.

-> IO () 

Requests loading of the given content with the specified mime_type and base_uri. If mime_type is Nothing, "text/html" is assumed. If want control over the encoding use webViewLoadByteString

webViewGetLoadStatus :: WebViewClass self => self -> IO LoadStatus Source #

Determines the current status of the load.

Reload

webViewStopLoading :: WebViewClass self => self -> IO () Source #

Stops and pending loads on the given data source.

webViewReload :: WebViewClass self => self -> IO () Source #

Reloads the WebView

webViewReloadBypassCache :: WebViewClass self => self -> IO () Source #

Reloads the WebView without using any cached data.

History

webViewCanGoBack Source #

Arguments

:: WebViewClass self 
=> self 
-> IO Bool

True if able to move back, False otherwise.

Determine whether WebView has a previous history item.

webViewCanGoForward Source #

Arguments

:: WebViewClass self 
=> self 
-> IO Bool

True if able to move forward, False otherwise.

Determine whether WebView has a next history item.

webViewGoBack :: WebViewClass self => self -> IO () Source #

Loads the previous history item.

webViewGoForward :: WebViewClass self => self -> IO () Source #

Loads the next history item.

webViewSetMaintainsBackForwardList Source #

Arguments

:: WebViewClass self 
=> self 
-> Bool

flag - to tell the view to maintain a back or forward list.

-> IO () 

Set the WebView to maintian a back or forward list of history items.

webViewGoToBackForwardItem Source #

Arguments

:: (WebViewClass self, WebHistoryItemClass item) 
=> self 
-> item 
-> IO Bool

True if loading of item is successful, False if not.

Go to the specified WebHistoryItem

webViewCanGoBackOrForward Source #

Arguments

:: WebViewClass self 
=> self 
-> Int

steps - the number of steps

-> IO Bool

True if able to move back or forward the given number of steps, False otherwise

Determines whether WebView has a history item of steps.

Negative values represent steps backward while positive values represent steps forward

webViewGoBackOrForward :: WebViewClass self => self -> Int -> IO () Source #

Loads the history item that is the number of steps away from the current item. Negative values represent steps backward while positive values represent steps forward.

Zoom

webViewGetZoomLevel :: WebViewClass self => self -> IO Float Source #

Returns the zoom level of WebView i.e. the factor by which elements in the page are scaled with respect to their original size.

webViewSetZoomLevel Source #

Arguments

:: WebViewClass self 
=> self 
-> Float

zoom_level - the new zoom level

-> IO () 

Sets the zoom level of WebView.

webViewZoomIn :: WebViewClass self => self -> IO () Source #

Increases the zoom level of WebView.

webViewZoomOut :: WebViewClass self => self -> IO () Source #

Decreases the zoom level of WebView.

webViewGetFullContentZoom Source #

Arguments

:: WebViewClass self 
=> self 
-> IO Bool

False if only text should be scaled(the default) True if the full content of the view should be scaled.

Returns whether the zoom level affects only text or all elements.

webViewSetFullContentZoom Source #

Arguments

:: WebViewClass self 
=> self 
-> Bool

full_content_zoom - False if only text should be scaled (the default) True if the full content of the view should be scaled.

-> IO () 

Sets whether the zoom level affects only text or all elements.

Clipboard

webViewCanCutClipboard :: WebViewClass self => self -> IO Bool Source #

Determines whether can cuts the current selection inside WebView to the clipboard

webViewCanCopyClipboard :: WebViewClass self => self -> IO Bool Source #

Determines whether can copies the current selection inside WebView to the clipboard

webViewCanPasteClipboard :: WebViewClass self => self -> IO Bool Source #

Determines whether can pastes the current contents of the clipboard to the WebView

webViewCutClipboard :: WebViewClass self => self -> IO () Source #

Cuts the current selection inside WebView to the clipboard.

webViewCopyClipboard :: WebViewClass self => self -> IO () Source #

Copies the current selection inside WebView to the clipboard.

webViewPasteClipboard :: WebViewClass self => self -> IO () Source #

Pastes the current contents of the clipboard to the WebView

Undo/Redo

webViewCanRedo :: WebViewClass self => self -> IO Bool Source #

Determines whether or not it is currently possible to redo the last editing command in the view

webViewCanUndo :: WebViewClass self => self -> IO Bool Source #

Determines whether or not it is currently possible to undo the last editing command in the view

webViewRedo :: WebViewClass self => self -> IO () Source #

Redoes the last editing command in the view, if possible.

webViewUndo :: WebViewClass self => self -> IO () Source #

Undoes the last editing command in the view, if possible.

Selection

webViewDeleteSelection :: WebViewClass self => self -> IO () Source #

Deletes the current selection inside the WebView

webViewHasSelection :: WebViewClass self => self -> IO Bool Source #

Determines whether text was selected

webViewSelectAll :: WebViewClass self => self -> IO () Source #

Attempts to select everything inside the WebView

Encoding

webViewGetEncoding Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> IO (Maybe string)

the default encoding or Nothing in case of failed

Returns the default encoding of the WebView

webViewSetCustomEncoding Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> Maybe string

encoding - the new encoding, or Nothing to restore the default encoding.

-> IO () 

Sets the current WebView encoding, without modifying the default one, and reloads the page

webViewGetCustomEncoding Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> IO (Maybe string)

the current encoding string or Nothing if there is none set.

Returns the current encoding of WebView,not the default encoding.

View Mode

webViewGetViewMode :: WebViewClass self => self -> IO ViewMode Source #

Gets the value of the "view-mode" property of the WebView

webViewGetViewSourceMode :: WebViewClass self => self -> IO Bool Source #

Returns whether WebView is in view source mode

webViewSetViewSourceMode :: WebViewClass self => self -> Bool -> IO () Source #

Set whether the view should be in view source mode. Setting this mode to (!(0)) before loading a URI will display the source of the web page in a nice and readable format.

Transparent

webViewGetTransparent :: WebViewClass self => self -> IO Bool Source #

Returns whether the WebView has a transparent background

webViewSetTransparent :: WebViewClass self => self -> Bool -> IO () Source #

Sets whether the WebKitWebView has a transparent background.

Pass False to have the WebView draw a solid background (the default), otherwise pass True.

Target List

webViewGetCopyTargetList :: WebViewClass self => self -> IO (Maybe TargetList) Source #

This function returns the list of targets this WebView can provide for clipboard copying and as DND source. The targets in the list are added with values from the WebViewTargetInfo enum, using targetListAdd and targetListAddTextTargets.

webViewGetPasteTargetList :: WebViewClass self => self -> IO (Maybe TargetList) Source #

This function returns the list of targets this WebView can provide for clipboard pasteing and as DND source. The targets in the list are added with values from the WebViewTargetInfo enum, using targetListAdd and targetListAddTextTargets.

Text Match

webViewMarkTextMatches Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> string

string - a string to look for

-> Bool

case_sensitive - whether to respect the case of text

-> Int

limit - the maximum number of strings to look for or 0 for all

-> IO Int

the number of strings highlighted

Attempts to highlight all occurances of string inside WebView

webViewUnMarkTextMatches :: WebViewClass self => self -> IO () Source #

Removes highlighting previously set by webViewMarkTextMarches

webViewSetHighlightTextMatches Source #

Arguments

:: WebViewClass self 
=> self 
-> Bool

highlight - whether to highlight text matches

-> IO () 

Highlights text matches previously marked by webViewMarkTextMatches

Icon

webViewGetIconUri :: (WebViewClass self, GlibString string) => self -> IO (Maybe string) Source #

Obtains the URI for the favicon for the given WebKitWebView, or Nothing if there is none.

  • Since 1.1.18

webViewTryGetFaviconPixbuf Source #

Arguments

:: WebView 
-> Int

the desired width for the icon

-> Int

the desired height for the icon

-> IO (Maybe Pixbuf)

a new reference to a Pixbuf, or Nothing.

Obtains a GdkPixbuf of the favicon for the given WebView. This will return Nothing if there is no icon for the current WebView or if the icon is in the database but not available at the moment of this call. Use webViewGetIconUri if you need to distinguish these cases.

Usually you want to connect to WebKitWebView::icon-loaded and call this method in the callback.

See also faviconDatabaseTryGetFaviconPixbuf. Contrary to this function the icon database one returns the URL of the page containing the icon.

Other

webViewExecuteScript Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> string

script - script to be executed

-> IO () 

Execute the script specified by script

webViewCanShowMimeType Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> string

mimetype - a MIME type

-> IO Bool

True if the mimetype can be displayed, otherwise False

Returns whether or not a mimetype can be displayed using this view.

webViewGetEditable :: WebViewClass self => self -> IO Bool Source #

Returns whether the user is allowed to edit the document.

webViewSetEditable :: WebViewClass self => self -> Bool -> IO () Source #

Sets whether allows the user to edit its HTML document.

webViewGetInspector :: WebViewClass self => self -> IO WebInspector Source #

Obtains the WebInspector associated with the WebView

webViewGetProgress Source #

Arguments

:: WebViewClass self 
=> self 
-> IO Double

the load progress

Determines the current progress of the load

webViewSearchText Source #

Arguments

:: (WebViewClass self, GlibString string) 
=> self 
-> string

text - a string to look for

-> Bool

case_sensitive - whether to respect the case of text

-> Bool

forward - whether to find forward or not

-> Bool

wrap - whether to continue looking at beginning after reaching the end

-> IO Bool

True on success or False on failure

Looks for a specified string inside WebView

webViewMoveCursor :: WebViewClass self => self -> MovementStep -> Int -> IO () Source #

Move the cursor in view as described by step and count.

webViewGetMainFrame :: WebViewClass self => self -> IO WebFrame Source #

Return the main WebFrame of the given WebView.

webViewGetFocusedFrame :: WebViewClass self => self -> IO (Maybe WebFrame) Source #

Return the focused WebFrame (if any) of the given WebView.

webViewSetWebSettings :: (WebViewClass self, WebSettingsClass settings) => self -> settings -> IO () Source #

Apply WebSettings to a given WebView

!!NOTE!!, currently lack of useful APIs of WebSettings in webkitgtk. If you want to set the encoding, font family or font size of the WebView, please use related functions.

webViewGetWebSettings :: WebViewClass self => self -> IO WebSettings Source #

Return the WebSettings currently used by WebView.

webViewGetWindowFeatures :: WebViewClass self => self -> IO WebWindowFeatures Source #

Returns the instance of WebKitWebWindowFeatures held by the given WebKitWebView.

webViewGetTitle :: (WebViewClass self, GlibString string) => self -> IO (Maybe string) Source #

Returns the title of WebView document, or Nothing in case of failure

webViewGetUri :: (WebViewClass self, GlibString string) => self -> IO (Maybe string) Source #

Returns the current URI of the contents displayed by the WebView, or Nothing in case of failure

Attributes

webViewZoomLevel :: WebViewClass self => Attr self Float Source #

Zoom level of the WebView instance

webViewFullContentZoom :: WebViewClass self => Attr self Bool Source #

Whether the full content is scaled when zooming

Default value: False

webViewEncoding :: (WebViewClass self, GlibString string) => ReadAttr self (Maybe string) Source #

The default encoding of the WebView instance

Default value: Nothing

webViewCustomEncoding :: (WebViewClass self, GlibString string) => Attr self (Maybe string) Source #

The custom encoding of the WebView instance

Default value: Nothing

webViewLoadStatus :: WebViewClass self => ReadAttr self LoadStatus Source #

Determines the current status of the load.

Default value: LoadFinished

webViewProgress :: WebViewClass self => ReadAttr self Double Source #

Determines the current progress of the load

Default Value: 1

webViewTitle :: (WebViewClass self, GlibString string) => ReadAttr self (Maybe string) Source #

Title of the WebView instance

webViewInspector :: WebViewClass self => ReadAttr self WebInspector Source #

The associated webInspector instance of the WebView

webViewWebSettings :: WebViewClass self => Attr self WebSettings Source #

The associated webSettings of the WebView instance

webViewViewSourceMode :: WebViewClass self => Attr self Bool Source #

view source mode of the WebView instance

webViewTransparent :: WebViewClass self => Attr self Bool Source #

transparent background of the WebView instance

webViewEditable :: WebViewClass self => Attr self Bool Source #

Whether content of the WebView can be modified by the user

Default value: False

webViewUri :: (WebViewClass self, GlibString string) => ReadAttr self (Maybe string) Source #

Returns the current URI of the contents displayed by the web_view.

Default value: Nothing

webViewCopyTargetList :: WebViewClass self => ReadAttr self (Maybe TargetList) Source #

The list of targets this web view supports for clipboard copying.

webViewPasteTargetList :: WebViewClass self => ReadAttr self (Maybe TargetList) Source #

The list of targets this web view supports for clipboard pasteing.

webViewIconUri :: (WebViewClass self, GlibString string) => ReadAttr self (Maybe string) Source #

The URI for the favicon for the WebKitWebView.

Default value: Nothing

  • Since 1.1.18

webViewImContext :: WebViewClass self => ReadAttr self IMContext Source #

The IMMulticontext for the WebKitWebView.

This is the input method context used for all text entry widgets inside the WebKitWebView. It can be used to generate context menu items for controlling the active input method.

  • Since 1.1.20

webViewViewMode :: WebViewClass self => Attr self ViewMode Source #

The "view-mode" property of the WebView

Signals

Loading

loadStarted :: WebViewClass self => Signal self (WebFrame -> IO ()) Source #

When a WebFrame begins to load, this signal is emitted

loadCommitted :: WebViewClass self => Signal self (WebFrame -> IO ()) Source #

When a WebFrame loaded the first data, this signal is emitted

progressChanged :: WebViewClass self => Signal self (Int -> IO ()) Source #

When the global progress changed, this signal is emitted

the global progress will be passed back to user function

loadFinished :: WebViewClass self => Signal self (WebFrame -> IO ()) Source #

When loading finished, this signal is emitted

loadError :: (WebViewClass self, GlibString string) => Signal self (WebFrame -> string -> GError -> IO Bool) Source #

When An error occurred while loading.

By default, if the signal is not handled, the WebView will display a stock error page.

You need to handle the signal if you want to provide your own error page.

The URI that triggered the error and the GError will be passed back to user function.

iconLoaded :: (WebViewClass self, GlibString string) => Signal self (string -> IO ()) Source #

Emitted after Icon loaded

documentLoadFinished :: WebViewClass self => Signal self (WebFrame -> IO ()) Source #

When document loading finished, this signal is emitted

resourceRequestStarting :: WebViewClass self => Signal self (WebFrame -> WebResource -> Maybe NetworkRequest -> Maybe NetworkResponse -> IO ()) Source #

Emitted when a request is about to be sent. You can modify the request while handling this signal. You can set the URI in the NetworkRequest object itself, and addremovereplace headers using the SoupMessage object it carries, if it is present. See networkRequestGetMessage. Setting the request URI to "about:blank" will effectively cause the request to load nothing, and can be used to disable the loading of specific resources.

Notice that information about an eventual redirect is available in response's SoupMessage, not in the SoupMessage carried by the request. If response is NULL, then this is not a redirected request.

The WebResource object will be the same throughout all the lifetime of the resource, but the contents may change from inbetween signal emissions.

titleChanged :: (WebViewClass self, GlibString string) => Signal self (WebFrame -> string -> IO ()) Source #

When Document title changed, this signal is emitted.

It can be used to set the Application Window title.

webframe - which WebFrame changes the document title.

title - current title string.

Clipboard

copyClipboard :: WebViewClass self => Signal self (IO ()) Source #

The copyClipboard signal is a keybinding signal which gets emitted to copy the selection to the clipboard.

The default bindings for this signal are Ctrl-c and Ctrl-Insert.

cutClipboard :: WebViewClass self => Signal self (IO ()) Source #

The cutClipboard signal is a keybinding signal which gets emitted to cut the selection to the clipboard.

The default bindings for this signal are Ctrl-x and Shift-Delete.

pasteClipboard :: WebViewClass self => Signal self (IO ()) Source #

The pasteClipboard signal is a keybinding signal which gets emitted to paste the contents of the clipboard into the Web view.

The default bindings for this signal are Ctrl-v and Shift-Insert.

Script

consoleMessage :: (WebViewClass self, GlibString string) => Signal self (string -> string -> Int -> string -> IO Bool) Source #

A JavaScript console message was created.

scriptAlert :: (WebViewClass self, GlibString string) => Signal self (WebFrame -> string -> IO Bool) Source #

A JavaScript alert dialog was created.

scriptConfirm :: (WebViewClass self, GlibString string) => Signal self (WebFrame -> string -> IO Bool) Source #

A JavaScript confirm dialog was created, providing Yes and No buttons.

scriptPrompt :: (WebViewClass self, GlibString string) => Signal self (WebFrame -> string -> string -> IO Bool) Source #

A JavaScript prompt dialog was created, providing an entry to input text.

statusBarTextChanged :: (WebViewClass self, GlibString string) => Signal self (string -> IO ()) Source #

When status-bar text changed, this signal will emitted.

populatePopup :: WebViewClass self => Signal self (Menu -> IO ()) Source #

When a context menu is about to be displayed this signal is emitted.

Selection/edition

editingBegan :: WebViewClass self => Signal self (IO ()) Source #

editingEnded :: WebViewClass self => Signal self (IO ()) Source #

selectAll :: WebViewClass self => Signal self (IO ()) Source #

The selectAll signal is a keybinding signal which gets emitted to select the complete contents of the text view.

The default bindings for this signal is Ctrl-a.

selectionChanged :: WebViewClass self => Signal self (IO ()) Source #

When selection changed, this signal is emitted.

Decision request

mimeTypePolicyDecisionRequested :: (WebViewClass self, GlibString string) => Signal self (WebFrame -> NetworkRequest -> string -> WebPolicyDecision -> IO Bool) Source #

Decide whether or not to display the given MIME type. If this signal is not handled, the default behavior is to show the content of the requested URI if WebKit can show this MIME type and the content disposition is not a download; if WebKit is not able to show the MIME type nothing happens.

Notice that if you return True, meaning that you handled the signal, you are expected to be aware of the Content-Disposition header. A value of "attachment" usually indicates a download regardless of the MIME type, see also soupMessageHeadersGetContentDisposition' And you must call webPolicyDecisionIgnore, webPolicyDecisionDownload, or webPolicyDecisionUse on the webPolicyDecision object.

navigationPolicyDecisionRequested :: WebViewClass self => Signal self (WebFrame -> NetworkRequest -> WebNavigationAction -> WebPolicyDecision -> IO Bool) Source #

Emitted when frame requests a navigation to another page. If this signal is not handled, the default behavior is to allow the navigation.

Notice that if you return True, meaning that you handled the signal, you are expected to be aware of the Content-Disposition header. A value of "attachment" usually indicates a download regardless of the MIME type, see also soupMessageHeadersGetContentDisposition' And you must call webPolicyDecisionIgnore, webPolicyDecisionDownload, or webPolicyDecisionUse on the webPolicyDecision object.

newWindowPolicyDecisionRequested :: WebViewClass self => Signal self (WebFrame -> NetworkRequest -> WebNavigationAction -> WebPolicyDecision -> IO Bool) Source #

Emitted when frame requests opening a new window. With this signal the browser can use the context of the request to decide about the new window. If the request is not handled the default behavior is to allow opening the new window to load the URI, which will cause a createWebView signal emission where the browser handles the new window action but without information of the context that caused the navigation. The following navigationPolicyDecisionRequested emissions will load the page after the creation of the new window just with the information of this new navigation context, without any information about the action that made this new window to be opened.

Notice that if you return True, meaning that you handled the signal, you are expected to be aware of the Content-Disposition header. A value of "attachment" usually indicates a download regardless of the MIME type, see also soupMessageHeadersGetContentDisposition' And you must call webPolicyDecisionIgnore, webPolicyDecisionDownload, or webPolicyDecisionUse on the webPolicyDecision object.

geolocationPolicyDecisionCancelled :: WebViewClass self => Signal self (WebFrame -> IO ()) Source #

When a frame wants to cancel geolocation permission it had requested before.

  • Since 1.1.23

geolocationPolicyDecisionRequested :: WebViewClass self => Signal self (WebFrame -> GeolocationPolicyDecision -> IO Bool) Source #

When a frame wants to get its geolocation permission. The receiver must reply with a boolean wether it handled or not the request. If the request is not handled, default behaviour is to deny geolocation.

  • Since 1.1.23

Display

moveCursor :: WebViewClass self => Signal self (MovementStep -> Int -> IO Bool) Source #

The moveCursor will be emitted to apply the cursor movement described by its parameters to the view.

setScrollAdjustments :: WebViewClass self => Signal self (Adjustment -> Adjustment -> IO ()) Source #

When set scroll adjustments, this signal is emitted.

Other

hoveringOverLink :: (WebViewClass self, GlibString string) => Signal self (Maybe string -> Maybe string -> IO ()) Source #

When the cursor is over a link, this signal is emitted.

title - the link's title or Nothing in case of failure.

uri - the URI the link points to or Nothing in case of failure.

webViewReady :: WebViewClass self => Signal self (IO Bool) Source #

Emitted after new WebView instance had been created in onCreateWebView user function when the new WebView should be displayed to the user.

All the information about how the window should look, including size,position,whether the location, status and scroll bars should be displayed, is ready set.

closeWebView :: WebViewClass self => Signal self (IO Bool) Source #

Emitted when closing a WebView is requested.

This occurs when a call is made from JavaScript's window.close function. The default signal handler does not do anything. It is the owner's responsibility to hide or delete the WebView, if necessary.

User function should return True to stop the handlers from being invoked for the event or False to propagate the event furter

printRequested :: WebViewClass self => Signal self (WebFrame -> IO Bool) Source #

Emitted when printing is requested by the frame, usually because of a javascript call. When handling this signal you should call webFramePrintFull or webFramePrint to do the actual printing.

The default handler will present a print dialog and carry a print operation. Notice that this means that if you intend to ignore a print request you must connect to this signal, and return True.

databaseQuotaExceeded :: WebViewClass self => Signal self (WebFrame -> WebDatabase -> IO ()) Source #

The databaseQuotaExceeded signal will be emitted when a Web Database exceeds the quota of its security origin. This signal may be used to increase the size of the quota before the originating operation fails.

downloadRequested :: WebViewClass self => Signal self (Download -> IO Bool) Source #

Emitted after A new Download is being requested.

By default, if the signal is not handled, the download is cancelled.

Notice that while handling this signal you must set the target URI using downloadSetDestinationUri

If you intend to handle downloads yourself, return False in user function.

redo :: WebViewClass self => Signal self (IO ()) Source #

The "redo" signal is a keybinding signal which gets emitted to redo the last editing command.

The default binding for this signal is Ctrl-Shift-z

undo :: WebViewClass self => Signal self (IO ()) Source #

The "undo" signal is a keybinding signal which gets emitted to undo the last editing command.

The default binding for this signal is Ctrl-z