package com.google.collide.client.ui.tree;
import elemental.html.Element;
import elemental.html.SpanElement;
/**
* Flyweight renderer whose job it is to take a NodeData and construct the
* appropriate DOM structure for the tree node contents.
*
* @param <D> The type of data we want to render.
*/
public interface NodeRenderer<D> {
/**
* Takes in a {@link SpanElement} constructed via a call to
* {@link #renderNodeContents} and returns an element whose contract is that
* it contains only text corresponding to the key for the node's underlying
* data.
*
* This ofcourse depends on the structure that was generated via the call to
* {@link #renderNodeContents}.
*/
Element getNodeKeyTextContainer(SpanElement treeNodeLabel);
/**
* Constructs the label portion of a {@link TreeNodeElement}. Labels can have
* arbitrary DOM structure, with one constraint. At least one element MUST
* contain only text that corresponds to the String key for the underlying
* node's data.
*/
SpanElement renderNodeContents(D data);
/**
* Updates the node's contents to reflect the current state of the node.
*
* @param treeNode the tree node that contains the rendered node contents
*/
void updateNodeContents(TreeNodeElement<D> treeNode);
}