The following sections explain how to use the selection
interactors.
SelectionInteractor
The SelectionInteractor manages the interaction between its graph and its
Selection
object,
by adding and removing the selected elements. By default, when you
click an element, the selection is empty, and the clicked element
is selected. If you click an element while holding the Ctrl key, the
clicked element is added to the selection. If the element is already
selected, it is removed from the selection. If you click a free area
of the diagram, the selection is empty. The
SelectionInteractor
can
be used also without a Diagram
widget,
by enabling it in the graph:graph = surface.createGraph(); graph.setSelect(true);
MarqueeSelectionInteractor
The MarqueeSelectionInteractor is available in the
DiagramEditor
widget.
It allows you to select multiple elements by selecting a rectangular
area of the diagram.When you click a free area of the diagram and drag the
mouse, a translucent rectangle is drawn in the
Viewport
.
When you release the mouse button, the bounded elements are selected.
By default, partially bounded elements are included in the marquee
selection. However, if you want to include only fully bounded elements
in the marquee selection, you can set the setPartialSelectionEnabled method to false
.
The modes of the MarqueeSelectionInteractor can
be changed through the DiagramEditor by
using the setMarqueeMode(mode) method.
- Top level only:Default mode. Selects only the top-level elements (the ones that are created in the graph). Set this mode by using the topLevelOnly constant.
- Top parent:Selects only the highest parent of the selected elements. For example, if a complete subgraph is bounded, just the subgraph is selected, but not its children. If the subgraph is not bounded by the marquee, its bounded children are selected. Set this mode by using the topParent constant.
- All:Selects all the bounded elements. Set this mode by using the all constant.
Multiple selection is also possible. If the user repeats
the marquee selection with the appropriate modifier key pressed (Ctrl,
by default), the selected elements are added to the selection, without
clearing the pre-existent ones.