Dojo: The Definitive Guide

Dropping

Thus far, this chapter has focused on dragging objects around on the screen. This section wraps up the discussion by focusing in on the dropping part of it all. To get started, let's first take a look at dojo.dnd.Source, a special container class the toolkit provides a drag-and-drop source. A Source can also act as a target for a drop, but as we'll see in a moment, you can also specify a "pure" target with dojo.dnd.Target. While a Source may act as an origin and a destination, a Target may only act as a destination.

Creating a Source is just like creating a Moveable ; you call the constructor function and pass in a node as the first argument and an Object of parameters as the second argument, like so. Table 7-3 lists the relevant methods.

Table 7-3. Creating and destroying a Source

Name	Comment
dojo.dnd.Source(/*DOMNode*/node, /*Object*/params)	Constructor method for creation. Valid values for params are provided in Table 7-1.
destroy( )	Prepares the Object to be garbage-collected.

Table 7-4 summarizes key parameters involved in the creation of a Source object.

Table 7-4. Configuration parameters for Source's params in Table 7-3

Parameter	Type	Comment
isSource	boolean	true by default; if false, prevents drag action from being possible.
horizontal	boolean	false by default; if true, constructs a horizontal layout (inline HTML elements required).
copyOnly	boolean	false by default; if true, always copies items instead of moving them (no Ctrl-key required).
skipform	boolean	false by default; like