tt-rss/lib/dijit/tree/ObjectStoreModel.js.uncompressed.js
2013-03-18 10:26:26 +04:00

250 行
8.5 KiB
JavaScript

define("dijit/tree/ObjectStoreModel", [
"dojo/_base/array", // array.filter array.forEach array.indexOf array.some
"dojo/aspect", // aspect.before, aspect.after
"dojo/_base/declare", // declare
"dojo/_base/lang", // lang.hitch
"dojo/when"
], function(array, aspect, declare, lang, when){
// module:
// dijit/tree/ObjectStoreModel
return declare("dijit.tree.ObjectStoreModel", null, {
// summary:
// Implements dijit/tree/model connecting dijit/Tree to a dojo/store/api/Store that implements
// getChildren().
//
// If getChildren() returns an array with an observe() method, then it will be leveraged to reflect
// store updates to the tree. So, this class will work best when:
//
// 1. the store implements dojo/store/Observable
// 2. getChildren() is implemented as a query to the server (i.e. it calls store.query())
//
// Drag and Drop: To support drag and drop, besides implementing getChildren()
// and dojo/store/Observable, the store must support the parent option to put().
// And in order to have child elements ordered according to how the user dropped them,
// put() must support the before option.
// store: dojo/store/api/Store
// Underlying store
store: null,
// labelAttr: String
// Get label for tree node from this attribute
labelAttr: "name",
// root: [readonly] Object
// Pointer to the root item from the dojo/store/api/Store (read only, not a parameter)
root: null,
// query: anything
// Specifies datastore query to return the root item for the tree.
// Must only return a single item. Alternately can just pass in pointer
// to root item.
// example:
// | {id:'ROOT'}
query: null,
constructor: function(/* Object */ args){
// summary:
// Passed the arguments listed above (store, etc)
// tags:
// private
lang.mixin(this, args);
this.childrenCache = {}; // map from id to array of children
},
destroy: function(){
// TODO: should cancel any in-progress processing of getRoot(), getChildren()
for(var id in this.childrenCache){
this.childrenCache[id].close && this.childrenCache[id].close();
}
},
// =======================================================================
// Methods for traversing hierarchy
getRoot: function(onItem, onError){
// summary:
// Calls onItem with the root item for the tree, possibly a fabricated item.
// Calls onError on error.
if(this.root){
onItem(this.root);
}else{
var res;
when(res = this.store.query(this.query),
lang.hitch(this, function(items){
//console.log("queried root: ", res);
if(items.length != 1){
throw new Error("dijit.tree.ObjectStoreModel: root query returned " + items.length +
" items, but must return exactly one");
}
this.root = items[0];
onItem(this.root);
// Setup listener to detect if root item changes
if(res.observe){
res.observe(lang.hitch(this, function(obj){
// Presumably removedFrom == insertedInto == 1, and this call indicates item has changed.
//console.log("root changed: ", obj);
this.onChange(obj);
}), true); // true to listen for updates to obj
}
}),
onError
);
}
},
mayHaveChildren: function(/*===== item =====*/){
// summary:
// Tells if an item has or may have children. Implementing logic here
// avoids showing +/- expando icon for nodes that we know don't have children.
// (For efficiency reasons we may not want to check if an element actually
// has children until user clicks the expando node).
//
// Application code should override this method based on the data, for example
// it could be `return item.leaf == true;`.
// item: Object
// Item from the dojo/store
return true;
},
getChildren: function(/*Object*/ parentItem, /*function(items)*/ onComplete, /*function*/ onError){
// summary:
// Calls onComplete() with array of child items of given parent item.
// parentItem:
// Item from the dojo/store
var id = this.store.getIdentity(parentItem);
if(this.childrenCache[id]){
when(this.childrenCache[id], onComplete, onError);
return;
}
var res = this.childrenCache[id] = this.store.getChildren(parentItem);
// User callback
when(res, onComplete, onError);
// Setup listener in case children list changes, or the item(s) in the children list are
// updated in some way.
if(res.observe){
res.observe(lang.hitch(this, function(obj, removedFrom, insertedInto){
//console.log("observe on children of ", id, ": ", obj, removedFrom, insertedInto);
// If removedFrom == insertedInto, this call indicates that the item has changed.
// Even if removedFrom != insertedInto, the item may have changed.
this.onChange(obj);
if(removedFrom != insertedInto){
// Indicates an item was added, removed, or re-parented. The children[] array (returned from
// res.then(...)) has already been updated (like a live collection), so just use it.
when(res, lang.hitch(this, "onChildrenChange", parentItem));
}
}), true); // true means to notify on item changes
}
},
// =======================================================================
// Inspecting items
isItem: function(/*===== something =====*/){
return true; // Boolean
},
fetchItemByIdentity: function(/* object */ keywordArgs){
this.store.get(keywordArgs.identity).then(
lang.hitch(keywordArgs.scope, keywordArgs.onItem),
lang.hitch(keywordArgs.scope, keywordArgs.onError)
);
},
getIdentity: function(/* item */ item){
return this.store.getIdentity(item); // Object
},
getLabel: function(/*dojo/data/Item*/ item){
// summary:
// Get the label for an item
return item[this.labelAttr]; // String
},
// =======================================================================
// Write interface, for DnD
newItem: function(/* dijit/tree/dndSource.__Item */ args, /*Item*/ parent, /*int?*/ insertIndex, /*Item*/ before){
// summary:
// Creates a new item. See `dojo/data/api/Write` for details on args.
// Used in drag & drop when item from external source dropped onto tree.
return this.store.put(args, {
parent: parent,
before: before
});
},
pasteItem: function(/*Item*/ childItem, /*Item*/ oldParentItem, /*Item*/ newParentItem,
/*Boolean*/ bCopy, /*int?*/ insertIndex, /*Item*/ before){
// summary:
// Move or copy an item from one parent item to another.
// Used in drag & drop
if(!bCopy){
// In order for DnD moves to work correctly, childItem needs to be orphaned from oldParentItem
// before being adopted by newParentItem. That way, the TreeNode is moved rather than
// an additional TreeNode being created, and the old TreeNode subsequently being deleted.
// The latter loses information such as selection and opened/closed children TreeNodes.
// Unfortunately simply calling this.store.put() will send notifications in a random order, based
// on when the TreeNodes in question originally appeared, and not based on the drag-from
// TreeNode vs. the drop-onto TreeNode.
var oldParentChildren = [].concat(this.childrenCache[this.getIdentity(oldParentItem)]), // concat to make copy
index = array.indexOf(oldParentChildren, childItem);
oldParentChildren.splice(index, 1);
this.onChildrenChange(oldParentItem, oldParentChildren);
}
return this.store.put(childItem, {
overwrite: true,
parent: newParentItem,
before: before
});
},
// =======================================================================
// Callbacks
onChange: function(/*dojo/data/Item*/ /*===== item =====*/){
// summary:
// Callback whenever an item has changed, so that Tree
// can update the label, icon, etc. Note that changes
// to an item's children or parent(s) will trigger an
// onChildrenChange() so you can ignore those changes here.
// tags:
// callback
},
onChildrenChange: function(/*===== parent, newChildrenList =====*/){
// summary:
// Callback to do notifications about new, updated, or deleted items.
// parent: dojo/data/Item
// newChildrenList: Object[]
// Items from the store
// tags:
// callback
},
onDelete: function(/*dojo/data/Item*/ /*===== item =====*/){
// summary:
// Callback when an item has been deleted.
// Actually we have no way of knowing this with the new dojo.store API,
// so this method is never called (but it's left here since Tree connects
// to it).
// tags:
// callback
}
});
});