Create User Interfaces - JavaFX: Developing Rich Internet Applications - page 121

There is a trick that this lets us do for empty cells. Notice the empty space in col-
umn 2, row 3, right below the “JavaFX” text. To achieve this, all we had to do
was assign an empty Group, Group{} , node to this position. Because the column
width and row height will be sized to hold the maximum width and height for the
column and row, respectively, then this row and column appears to be empty.
This is because an empty Group is essentially dimensionless.
The full listing is on the topic's Web site at http://www.jfxbook.com.
Input Events
JavaFX supports two types of input events: javafx . scene.input.MouseEvent
and javafx.scene.input.KeyEvent . Mouse events are generated by actions
with the mouse and include mouse button actions like clicked, pressed, and
released. Also, events are generated for mouse movement like moved, dragged,
enter, and exit and for mouse wheel move events.
Key events are generated when the user presses, releases, and “types” keys from
the keyboard. Key type events are at a higher level than press and release events
and multiple key pressed/released events may map to one typed event.
There is an important attribute in javafx.scene.Node , blocksMouse , that con-
trols delivery of mouse events. Normally, when a mouse event is generated, the
runtime system delivers the event to all the nodes that intersect with the mouse
coordinate. If you set blocksMouse to true on a node, that node will consume the
mouse event and it will no longer propagate up the scene graph tree. If you do
not want mouse events sent to other nodes that are visually blocked by a node,
set blocksMouse to true on that node.
Mouse Events
javafx.scene.Node defines eight mouse event actions; these are
Mouse Actions
onMouseClicked: function(e:MouseEvent): Void
onMousePressed: function(e:MouseEvent): Void
onMouseReleased function(e:MouseEvent): Void
onMouseEntered: function(e:MouseEvent): Void
onMouseExited: function(e:MouseEvent): Void
onMouseMoved: function(e:MouseEvent): Void
onMouseDragged: function(e:MouseEvent): Void
onMouseWheelMoved: function(e: MouseEvent): Void