gtk-Clipboards {RGtk2} | R Documentation

## Clipboards

### Description

Storing data on clipboards

### Methods and Functions

`gtkClipboardGet(selection = "GDK_SELECTION_CLIPBOARD")`
`gtkClipboardGetForDisplay(display, selection = "GDK_SELECTION_CLIPBOARD")`
`gtkClipboardGetDisplay(object)`
`gtkClipboardSetWithData(object, targets, get.func, user.data = NULL)`
`gtkClipboardSetWithOwner(object, targets, get.func, owner = NULL)`
`gtkClipboardGetOwner(object)`
`gtkClipboardClear(object)`
`gtkClipboardSetText(object, text, len = -1)`
`gtkClipboardSetImage(object, pixbuf)`
`gtkClipboardRequestContents(object, target, callback, user.data = NULL)`
`gtkClipboardRequestText(object, callback, user.data = NULL)`
`gtkClipboardRequestImage(object, callback, user.data = NULL)`
`gtkClipboardRequestTargets(object, callback, user.data = NULL)`
`gtkClipboardRequestRichText(object, buffer, callback, user.data)`
`gtkClipboardRequestUris(object, callback, user.data)`
`gtkClipboardWaitForContents(object, target)`
`gtkClipboardWaitForText(object)`
`gtkClipboardWaitForImage(object)`
`gtkClipboardWaitForRichText(object, buffer)`
`gtkClipboardWaitForUris(object)`
`gtkClipboardWaitIsTextAvailable(object)`
`gtkClipboardWaitIsImageAvailable(object)`
`gtkClipboardWaitIsRichTextAvailable(object, buffer)`
`gtkClipboardWaitIsUrisAvailable(object)`
`gtkClipboardWaitForTargets(object)`
`gtkClipboardWaitIsTargetAvailable(object, target)`
`gtkClipboardSetCanStore(object, targets)`
`gtkClipboardStore(object)`
`gtkClipboard(display, selection = "GDK_SELECTION_CLIPBOARD")`

### Hierarchy

    GObject
       +----GtkClipboard

### Detailed Description

The `GtkClipboard` object represents a clipboard of data shared between different processes or between different widgets in the same process. Each clipboard is identified by a name encoded as a `GdkAtom`. (Conversion to and from strings can be done with `gdkAtomIntern` and `gdkAtomName`.) The default clipboard corresponds to the "CLIPBOARD" atom; another commonly used clipboard is the "PRIMARY" clipboard, which, in X, traditionally contains the currently selected text.

To support having a number of different formats on the clipboard at the same time, the clipboard mechanism allows providing callbacks instead of the actual data. When you set the contents of the clipboard, you can either supply the data directly (via functions like `gtkClipboardSetText`), or you can supply a callback to be called at a later time when the data is needed (via `gtkClipboardSetWithData` or `gtkClipboardSetWithOwner`.) Providing a callback also avoids having to make copies of the data when it is not needed. `gtkClipboardSetWithData` and `gtkClipboardSetWithOwner` are quite similar; the choice between the two depends mostly on which is more convenient in a particular situation. The former is most useful when you want to have a blob of data with callbacks to convert it into the various data types that you advertise. When the `clear.func` you provided is called, you simply free the data blob. The latter is more useful when the contents of clipboard reflect the internal state of a `GObject` (As an example, for the PRIMARY clipboard, when an entry widget provides the clipboard's contents the contents are simply the text within the selected region.) If the contents change, the entry widget can call `gtkClipboardSetWithOwner` to update the timestamp for clipboard ownership, without having to worry about `clear.func` being called.

Requesting the data from the clipboard is essentially asynchronous. If the contents of the clipboard are provided within the same process, then a direct function call will be made to retrieve the data, but if they are provided by another process, then the data needs to be retrieved from the other process, which may take some time. To avoid blocking the user interface, the call to request the selection, `gtkClipboardRequestContents` takes a callback that will be called when the contents are received (or when the request fails.) If you don't want to deal with providing a separate callback, you can also use `gtkClipboardWaitForContents`. What this does is run the GLib main loop recursively waiting for the contents. This can simplify the code flow, but you still have to be aware that other callbacks in your program can be called while this recursive mainloop is running.

Along with the functions to get the clipboard contents as an arbitrary data chunk, there are also functions to retrieve it as text, `gtkClipboardRequestText` and `gtkClipboardWaitForText`. These functions take care of determining which formats are advertised by the clipboard provider, asking for the clipboard in the best available format and converting the results into the UTF-8 encoding. (The standard form for representing strings in GTK+.)

### Structures

`GtkClipboard`

  undocumented

### Convenient Construction

`gtkClipboard` is the equivalent of `gtkClipboardGetForDisplay`.

### User Functions

`GtkClipboardReceivedFunc(clipboard, selection.data, data)`

  A function to be called when the results of `gtkClipboardRequestContents` are received, or when the request fails.

  `clipboard`

    the `GtkClipboard`

  `selection.data`

    a `GtkSelectionData` containing the data was received. If retrieving the data failed, then then length field of `selection.data` will be negative.

  `data`

    the `user.data` supplied to `gtkClipboardRequestContents`.

`GtkClipboardTextReceivedFunc(clipboard, text, data)`

  A function to be called when the results of `gtkClipboardRequestText` are received, or when the request fails.

  `clipboard`

    the `GtkClipboard`

  `text`

    the text received, as a UTF-8 encoded string, or `NULL` if retrieving the data failed.

  `data`

    the `user.data` supplied to `gtkClipboardRequestText`.

`GtkClipboardImageReceivedFunc(clipboard, pixbuf, data)`

  A function to be called when the results of `gtkClipboardRequestImage` are received, or when the request fails. Since 2.6

  `clipboard`

    the `GtkClipboard`

  `pixbuf`

    the received image

  `data`

    the `user.data` supplied to `gtkClipboardRequestImage`.

`GtkClipboardTargetsReceivedFunc(clipboard, atoms, n.atoms, data)`

  A function to be called when the results of `gtkClipboardRequestTargets` are received, or when the request fails. Since 2.4

  `clipboard`

    the `GtkClipboard`

  `atoms`

    the supported targets, as list of `GdkAtom`, or `NULL` if retrieving the data failed.

  `n.atoms`

    the length of the `atoms` list.

  `data`

    the `user.data` supplied to `gtkClipboardRequestTargets`.

`GtkClipboardRichTextReceivedFunc()`

  undocumented

`GtkClipboardURIReceivedFunc()`

  undocumented

`GtkClipboardGetFunc(clipboard, selection.data, info, user.data.or.owner)`

  A function that will be called to provide the contents of the selection. If multiple types of data were advertised, the requested type can be determined from the `info` parameter or by checking the target field of `selection.data`. If the data could successfully be converted into then it should be stored into the `selection.data` object by calling `gtkSelectionDataSet` (or related functions such as `gtkSelectionDataSetText`). If no data is set, the requestor will be informed that the attempt to get the data failed.

  `clipboard`

    the `GtkClipboard`

  `selection.data`

    a `GtkSelectionData` argument in which the requested data should be stored.

  `info`

    the info field corresponding to the requested target from the `GtkTargetEntry` list passed to `gtkClipboardSetWithData` or `gtkClipboardSetWithOwner`.

  `user.data.or.owner`

    the `user.data` argument passed to `gtkClipboardSetWithData`, or the `owner` argument passed to `gtkClipboardSetWithOwner`

`GtkClipboardClearFunc(clipboard, user.data.or.owner)`

  A function that will be called when the contents of the clipboard are changed or cleared. Once this has called, the `user.data.or.owner` argument will not be used again.

  `clipboard`

    the `GtkClipboard`

  `user.data.or.owner`

    the `user.data` argument passed to `gtkClipboardSetWithData`, or the `owner` argument passed to `gtkClipboardSetWithOwner`

### Signals

`owner-change(clipboard, event, user.data)`

  The ::owner-change signal is emitted when GTK+ receives an event that indicates that the ownership of the selection associated with `clipboard` has changed. Since 2.6

  `clipboard`

    the `GtkClipboard` on which the signal is emitted

  `event`

    the `GdkEventOwnerChange` event

  `user.data`

    user data set when the signal handler was connected.

### Author(s)

Derived by RGtkGen from GTK+ documentation

### References

https://developer.gnome.org/gtk2/stable/gtk2-Clipboards.html

[Package RGtk2 version 2.20.36.3 Index]