Hi,
looking at what Opera needs to support I drafted a specish text for
clipboard events. Something for this WG?
--
Hallvord R. M. Steen, Core Tester, Opera Software
http://www.opera.com http://my.opera.com/hallvors/Title: Clipboard API and events
Clipboard API and events
Status of this document
This is a Clipboard API event specification draft edited by Hallvord R. M. Steen, Opera Software. Although I've used W3C stylesheets for convenience this spec is not currently adopted by the W3C.
Events
copy event
When the user initiates a copy operation, the implementation must fire a copy event. Its default action is to place the selected data on the clipboard. If there is no selection, the event has no default action.
Typecopy
InterfaceClipboardEvent
CancelableYes
BubblesYes
TargetElements
cut event
When the user initiates a cut operation, the implementation must fire a cut event. In an editable context, its default action is to place the selected data on the clipboard and remove the selection from the document.
In a non-editable context, or if there is no selection, the cut event has no default action.
Typecut
InterfaceClipboardEvent
CancelableYes
BubblesYes
TargetElements
paste event
When the user initiates a paste operation, the implementation must fire a paste event.
If the cursor is in an editable element, the default action is to insert clipboard data in the most suitable format supported for the given context.
In an editable context, the paste event's target property refers to the element that contains the start of the selection.
In a non-editable document, the event is targeted at a node focused by clicking or by an interactive cursor. If the node that has focus is not a text node, the event is targeted at the BODY element.
The paste event has no default action in a non-editable context.
Typepaste
InterfaceClipboardEvent
CancelableYes
BubblesYes
TargetElement
Interface ClipboardData
How should we define the relationship to the HTML5 DataTransfer interface? Can DataTransfer inherit from ClipboardData and add the drag-and-drop stuff, or should we just defer to HTML5 for all of this?
IDL definition
interface ClipboardData {
void clearData( in optional DOMString type );
DOMString getData(in DOMString type);
void setData(in DOMString type, in DOMString data);
DOMStringList types;
}
Attributes
types
The types property returns a DOMStringList of MIME type strings. [RFC2046]. In the paste event, it lists those formats available on the clipboard the implementation supports returning to the script. In the copy and cut events, the types property returns a list of supported formats for the copy operation - for example, if the implementation supports copying plain text and HTML it would return a DOMStringList with the values 'text/plain' and 'text/html'.
The order of these values is undefined.
This .types spec is slightly different from the HTML5 DnD .types - consistent enough to make sense to authors and implementers?
Methods
getData
Calling getData() from within a paste event handler will return the clipboard data in the specified format. An implementation must support 'text/plain' and should support 'text/html' to retrieve any HTML formatted data on the system clipboard.
If getData() is not called from within a paste event handler, or if the type is not available, the method returns undefined. Note: IE allows this, but it seems to go against user expectations
HTML5 says return empty string if data of that type is not found. WebKit returns undefined though..
If the method is called with too many or too few arguments, it throws a syntax error exception.
Note: for compatibility purposes, the value 'text' (case-insensitive) must be treated as 'text/plain'.
setData
Method exists in WebKit but doesn't seem to do anything
Calling setData() from within an event handler will modify the data which will be placed on the clipboard, for the specified format.
If the type argument is not supported, the setData() call does nothing.
setData() with unsupported type throws in IE
Calling setData() from a paste event handler will modify the data before it is inserted. Not what WebKit does (but its support for setData() is non-existant anyway). IE does this.
The default action of a copy and cut event is to place the selection on the clipboard. Hence, after calling setData() the script must cancel the default action of the event, otherwise the data placed on the clipboard with the setData() call will immediately be overwritten by the default action.
clearData
Calling clearData() empties the system clipboard if no argument is given, and removes the specified type of data from the clipboard if called with the optional type argument.
Clipboard event interface
IDL definition
interface ClipboardEvent : Event {
readonly attribute ClipboardData clipboardData;
void initClipboardEvent( in DOMString
