- Author:
- David Nickerson <nickerso@users.sourceforge.net>
- Date:
- 2009-07-16 02:00:03+12:00
- Desc:
- the starting point for the HH tutorial example
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/f6a8f90307388eb4b040ee3566b84d88b59247f7/dojo-presentation/js/dojo/dojox/wire/DataWire.js
dojo.provide("dojox.wire.DataWire");
dojo.require("dojox.wire.Wire");
dojo.declare("dojox.wire.DataWire", dojox.wire.Wire, {
// summary:
// A Wire for item attributes of data stores
// description:
// This class accesses item attributes of data stores with a dotted
// notation of attribute names specified to 'attribute' property,
// using data APIs of a data store specified to 'dataStore' property.
// The root object for this class must be an item of the data store.
// Intermediate attribute names in the dotted notation specify
// attributes for child items, which are used for repeated calls to
// data APIs until reached to a descendant attribute.
// Attribute names may have an array index, such as "a[0]", to
// identify an array element of the attribute value.
_wireClass: "dojox.wire.DataWire",
constructor: function(/*Object*/args){
// summary:
// Initialize properties
// description:
// If 'dataStore' property is not specified, but 'parent' property
// is specified, 'dataStore' property is copied from the parent.
// args:
// Arguments to initialize properties
// dataStore:
// A data store
// attribute:
// A dotted notation to a descendant attribute
if(!this.dataStore && this.parent){
this.dataStore = this.parent.dataStore;
}
},
_getValue: function(/*Object*/object){
// summary:
// Return an attribute value of an item
// description:
// This method uses a root item passed in 'object' argument and
// 'attribute' property to call getValue() method of
// 'dataStore'.
// If an attribute name have an array suffix ("[]"), getValues()
// method is called, instead.
// If an index is specified in the array suffix, an array element
// for the index is returned, instead of the array itself.
// object:
// A root item
// returns:
// A value found, otherwise 'undefined'
if(!object || !this.attribute || !this.dataStore){
return object; //Object
}
var value = object;
var list = this.attribute.split('.');
for(var i in list){
value = this._getAttributeValue(value, list[i]);
if(!value){
return undefined; //undefined
}
}
return value; //anything
},
_setValue: function(/*Object*/object, /*anything*/value){
// summary:
// Set an attribute value to an item
// description:
// This method uses a root item passed in 'object' argument and
// 'attribute' property to identify an item.
// Then, setValue() method of 'dataStore' is called with a leaf
// attribute name and 'value' argument.
// If an attribute name have an array suffix ("[]"), setValues()
// method is called, instead.
// If an index is specified in the array suffix, an array element
// for the index is set to 'value', instead of the array itself.
// object:
// A root item
// value:
// A value to set
// returns:
// 'object', or 'undefined' for invalid attribute
if(!object || !this.attribute || !this.dataStore){
return object; //Object
}
var item = object;
var list = this.attribute.split('.');
var last = list.length - 1;
for(var i = 0; i < last; i++){
item = this._getAttributeValue(item, list[i]);
if(!item){
return undefined; //undefined
}
}
this._setAttributeValue(item, list[last], value);
return object; //Object
},
_getAttributeValue: function(/*Object*/item, /*String*/attribute){
// summary:
// Return an attribute value of an item
// description:
// This method uses an item passed in 'item' argument and
// 'attribute' argument to call getValue() method of 'dataStore'.
// If an attribute name have an array suffix ("[]"), getValues()
// method is called, instead.
// If an index is specified in the array suffix, an array element
// for the index is returned, instead of the array itself.
// item:
// An item
// attribute
// An attribute name
// returns:
// A value found, otherwise 'undefined'
var value = undefined;
var i1 = attribute.indexOf('[');
if(i1 >= 0){
var i2 = attribute.indexOf(']');
var index = attribute.substring(i1 + 1, i2);
attribute = attribute.substring(0, i1);
var array = this.dataStore.getValues(item, attribute);
if(array){
if(!index){ // return array for "attribute[]"
value = array;
}else{
value = array[index];
}
}
}else{
value = this.dataStore.getValue(item, attribute);
}
return value; //anything
},
_setAttributeValue: function(/*Object*/item, /*String*/attribute, /*anything*/value){
// summary:
// Set an attribute value to an item
// description:
// This method uses an item passed in 'item' argument and
// 'attribute' argument to call setValue() method of 'dataStore'
// with 'value' argument.
// If an attribute name have an array suffix ("[]"), setValues()
// method is called, instead.
// If an index is specified in the array suffix, an array element
// for the index is set to 'value', instead of the array itself.
// item:
// An item
// attribute:
// An attribute name
// value:
// A value to set
var i1 = attribute.indexOf('[');
if(i1 >= 0){
var i2 = attribute.indexOf(']');
var index = attribute.substring(i1 + 1, i2);
attribute = attribute.substring(0, i1);
var array = null;
if(!index){ // replace whole array for "attribute[]"
array = value;
}else{
array = this.dataStore.getValues(item, attribute);
if(!array){
array = [];
}
array[index] = value;
}
this.dataStore.setValues(item, attribute, array);
}else{
this.dataStore.setValue(item, attribute, value);
}
}
});
