change handler for ggraphics
The change handler for ggraphics is called when a rubber-band selection is completed
The click handler is called on a mouse click. The handler object should pass in value for x, y
A GUI is made interactive by assigning handlers to user-generated
events, such as a mouse click, change of widget state, or keyboard
press. In gWidgets2 handlers are assigned through various
addHandlerXXX methods. The handlers are functions whose
first argument should expect a list with components obj (to
pass in the receiver object) and action (to pass in any
user-supplied value to the action argument). Some handlers
add other components, such as mouse position information on a
click, or key information on a keyboard event.
Default S3 method
The "changed" event varies wildly amongst the widgets, but is meant to be the most "obvious" one. Typically this is also similar to "selected".
Default S3 method
Add handler for clicked event
Default S3 method
Add handler for double click event
Default S3 method
This may not be supported by all toolkits.
Default S3 method
This may not be supported by all toolkits.
Default S3 method
This may not be supported by all toolkits.
Default S3 method
For table widgets (gtable, gdf) clicking the column
header should trigger this event. The column that is clicked on is
passed back in the component column.
Default S3 method
If defined (gtable, gdf) calls event handler for
double click enent. Passes back column information through
column component.
Default S3 method
Add handler for column right click event
Default S3 method
The select event defaults to the "changed" event.
Default S3 method
The "select" event is when a user "selects" an object, the "selection changed" event is when the selection changes. The distinction is in table and tree widgets where a user may select values with a single click yet want to initiate an action with a double click. The latter is the "addHandlerSelect" event, the former the "addHandlerSelectionChanged" event.
Default S3 method
When a widget has the focus, it will receive the keyboard input. This handler is called when a widget receives the focus.
Default S3 method
A blur or focus out event for a widget triggers this event handler
Default S3 method
When a widget is destroyed, a handler can be assigned to perform any clean up tasks that are needed.
Default S3 method
For gwindow objects this handler is called before the window is
closed. If this handler returns TRUE the window will be
closed, if FALSE the window will not be closed. In
contrast, the "destroy" handler does not allow conditional
destruction.
Default S3 method
Add handler for expose event (when a widget is exposed, say it had been covered)
Default S3 method
The "h" argument has components key for the key and possibly modifier for the modifier.
Default S3 method
Add handler for mousemotion events
Default S3 method
deprecated. See gtimer.
Defaults to adding a right-click mouse popup menu, better known as a context menu, though some toolkits have both this and the latter provided.
S3 method for popup menu
These menus are also known as context menus, though there isn't really a good mechanism within gWidgets2 to make the menu items context sensitive.
S3 method for popup menu
Alias for poor initial name choice
Alias for poor punctation choice
Drag and drop requires one to register widgets a sources for dragging, a widgets as a targets for dropping.
Default S3 method
The handler is called on the drop event. The component
dropdata passes in the value being transferred by dragging.
Default S3 method
When a drag event crosses over the object the handler is called.
Default S3 method
Block all handlers for an object. Removed via unblockHandlers.
S3 method to block all handlers
Block a handler
S3 method to block handler
The block is a counter that gets decremented. If more blockHandlers calls are made than unblockHandlers, the handlers will still be blocked.
S3 method to block handler
method call to unblock a blocked handler
S3 method to block handler
method call to unblock a remove permanently handler
S3 method to remove handler
## Default S3 method:
addHandlerChanged(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerClicked(obj, handler, action = NULL, ...)
addHandler(obj, signal, handler, action = NULL, ...)
## Default S3 method:
addHandler(obj, signal, handler, action = NULL, ...)
addHandlerChanged(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerChanged(obj, handler, action = NULL, ...)
addHandlerClicked(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerClicked(obj, handler, action = NULL, ...)
addHandlerDoubleclick(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerDoubleclick(obj, handler, action = NULL, ...)
addHandlerRightclick(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerRightclick(obj, handler, action = NULL, ...)
addHandlerShiftclick(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerShiftclick(obj, handler, action = NULL, ...)
addHandlerControlclick(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerControlclick(obj, handler, action = NULL, ...)
addHandlerColumnclicked(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerColumnclicked(obj, handler, action = NULL, ...)
addHandlerColumnDoubleclicked(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerColumnDoubleclicked(obj, handler, action = NULL,
...)
addHandlerColumnRightclicked(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerColumnRightclicked(obj, handler, action = NULL,
...)
addHandlerSelect(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerSelect(obj, handler, action = NULL, ...)
addHandlerSelectionChanged(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerSelectionChanged(obj, handler, action = NULL, ...)
addHandlerFocus(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerFocus(obj, handler, action = NULL, ...)
addHandlerBlur(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerBlur(obj, handler, action = NULL, ...)
addHandlerDestroy(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerDestroy(obj, handler, action = NULL, ...)
addHandlerUnrealize(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerUnrealize(obj, handler, action = NULL, ...)
addHandlerExpose(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerExpose(obj, handler, action = NULL, ...)
addHandlerKeystroke(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerKeystroke(obj, handler, action = NULL, ...)
addHandlerMouseMotion(obj, handler, action = NULL, ...)
## Default S3 method:
addHandlerMouseMotion(obj, handler, action = NULL, ...)
addHandlerIdle(...)
addPopupMenu(obj, menulist, action = NULL, ...)
## Default S3 method:
addPopupMenu(obj, menulist, action = NULL, ...)
addRightclickPopupMenu(obj, menulist, action = NULL, ...)
## Default S3 method:
addRightclickPopupMenu(obj, menulist, action = NULL, ...)
## Default S3 method:
addRightclickPopupMenu(obj, menulist, action = NULL, ...)
## Default S3 method:
addRightclickPopupMenu(obj, menulist, action = NULL, ...)
addDropSource(obj, handler, action = NULL, data.type = c("text", "object"),
...)
## Default S3 method:
addDropSource(obj, handler, action = NULL,
data.type = c("text", "object"), ...)
addDropTarget(obj, handler, action = NULL, ...)
## Default S3 method:
addDropTarget(obj, handler, action = NULL, ...)
addDragMotion(obj, handler, action = NULL, ...)
## Default S3 method:
addDragMotion(obj, handler, action = NULL, ...)
blockHandlers(obj, ...)
## Default S3 method:
blockHandlers(obj, ...)
blockHandler(obj, ID, ...)
## Default S3 method:
blockHandler(obj, ID, ...)
unblockHandlers(obj, ...)
## Default S3 method:
unblockHandlers(obj, ...)
unblockHandler(obj, ID, ...)
## Default S3 method:
unblockHandler(obj, ID, ...)
removeHandler(obj, ID, ...)
## Default S3 method:
removeHandler(obj, ID, ...)obj |
object receiving event and emitting a signal to the handler |
handler |
handler to assign when signal is emitted. A handler
is a function, its first argument should expect a list with
components |
action |
passed to handler to parameterize call. |
... |
passed along |
signal |
toolkit signal, e.g. "clicked" |
menulist |
a list of |
data.type |
Type of data returned. It is either text or an object |
ID |
returned by addHandler. If missing will try to block all handler passed to constructor |
Although the add_handler method, to which addHandler
dispatches, is basically the workhorse to add a handler to
response to a signal, it generally isn't called directly, as its
use is not cross toolkit. Rather, if possible, one should use the
addHandlerXXX methods to add a handler. These dispatch to
this (basically) but do so in a toolkit independent manner.
This call (and the others) returns a handler ID which may be used
for some toolkits later on to remove, block or unblock the
call. All handlers for a widget may be blocked or unblocked via
blockHandlers and unblockHandlers.
The "changed" event is also the one that a handler passed to the constructor is called on.
To specify the values that is transferred in a drag and drop
event, the handler specified here should return the value to pass
via drag and drop. It will appear as the dropdata component
of the list passed in as the first argument of the drop handler
a handler ID which can be used to block/unblock or remove the handler
This method is not toolkit independent, as the signal value depends on the toolkit
For the gWidgets2Qt package one can not block, unblock or remove a single handler, but rather must do all the objects handlers at once.
blockHandlers to block all handlers for widget
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.