webgui/www/extras/yui-ext/docs/output/JsonReader.jss.html
2007-07-05 04:23:55 +00:00

158 lines
No EOL
7.1 KiB
HTML

<html><head><title>JsonReader.js</title><link rel="stylesheet" type="text/css" href="../resources/style.css" media="screen"/></head><body><h1>JsonReader.js</h1><pre class="highlighted"><code><i>/**
* @class Ext.data.JsonReader
* @extends Ext.data.DataReader
* Data reader class to create an Array of Ext.data.Record objects from a JSON response
* based on mappings <b>in</b> a provided Ext.data.Record constructor.
* &lt;p&gt;
* The code below lists all configuration options.
* &lt;pre&gt;&lt;code&gt;
<b>var</b> RecordDef = Ext.data.Record.create([
{name: 'name', mapping: 'name'}, <i>// &quot;mapping&quot; property not needed <b>if</b> it's the same as &quot;name&quot;</i>
{name: 'occupation'}, <i>// This field will use &quot;occupation&quot; as the mapping.</i>
]);
<b>var</b> myReader = <b>new</b> Ext.data.JsonReader({
totalProperty: &quot;results&quot;, <i>// The property which contains the number of returned records (optional)</i>
root: &quot;rows&quot;, <i>// The property which contains an Array of record objects</i>
id: &quot;id&quot; <i>// The property within the record object that provides an ID <b>for</b> the record (optional)</i>
}, RecordDef);
&lt;/code&gt;&lt;/pre&gt;
* &lt;p&gt;
* This would consume a JSON file like <b>this</b>:
* &lt;pre&gt;&lt;code&gt;
{ 'results': 2, 'rows': [
{ 'id': 1, 'name': 'Bill', occupation: 'Gardener' },
{ 'id': 2, 'name': 'Ben', occupation: 'Horticulturalist' } ]
}
&lt;/code&gt;&lt;/pre&gt;
* @cfg {String} totalProperty Name of the property from which to retrieve the total number of records
* <b>in</b> the dataset. This is only needed <b>if</b> the whole dataset is not passed <b>in</b> one go, but is being
* paged from the remote server.
* @cfg {String} successProperty Name of the property from which to retrieve the success attribute used by forms.
* @cfg {String} root name of the property which contains the Array of row objects.
* @cfg {String} id Name of the property within a row object that contains a record identifier value.
* @constructor
* Create a <b>new</b> JsonReader
* @param {Object} meta Metadata configuration options
* @param {Object[]/Ext.data.Record constructor} recordType The record definition of the data record to produce.
*/</i>
Ext.data.JsonReader = <b>function</b>(meta, recordType){
Ext.data.JsonReader.superclass.constructor.call(<b>this</b>, meta, recordType);
};
Ext.extend(Ext.data.JsonReader, Ext.data.DataReader, {
<i>/**
* This method is only used by a DataProxy which has retrieved data from a remote server.
* @param {Object} response The XHR object which contains the JSON data <b>in</b> its responseText.
* @<b>return</b> {Object} data A data block which is used by an Ext.data.Store object as
* a cache of Ext.data.Records.
*/</i>
read : <b>function</b>(response){
<b>var</b> json = response.responseText;
<b>var</b> o = eval(&quot;(&quot;+json+&quot;)&quot;);
<b>if</b>(!o) {
throw {message: &quot;JsonReader.read: Json object not found&quot;};
}
<b>return</b> this.readRecords(o);
},
<i>/**
* @ignore
*/</i>
simpleAccess: <b>function</b>(obj, subsc) {
<b>return</b> obj[subsc];
},
<i>/**
* @ignore
*/</i>
getJsonAccessor: <b>function</b>(){
<b>var</b> re = /[\[\.]/;
<b>return</b> function(expr) {
try {
<b>return</b>(re.test(expr))
? <b>new</b> Function(&quot;obj&quot;, &quot;<b>return</b> obj.&quot; + expr)
: <b>function</b>(obj){
<b>return</b> obj[expr];
};
} catch(e){}
<b>return</b> Ext.emptyFn;
};
}(),
<i>/**
* Create a data block containing Ext.data.Records from an XML document.
* @param {Object} o An object which contains an Array of row objects <b>in</b> the property specified
* <b>in</b> the config as 'root, and optionally a property, specified <b>in</b> the config as 'totalProperty'
* which contains the total size of the dataset.
* @<b>return</b> {Object} data A data block which is used by an Ext.data.Store object as
* a cache of Ext.data.Records.
*/</i>
readRecords : <b>function</b>(o){
<i>/**
* After any data loads, the raw JSON data is available <b>for</b> further custom processing.
* @type Object
*/</i>
<b>this</b>.jsonData = o;
<b>var</b> s = <b>this</b>.meta, Record = <b>this</b>.recordType,
f = Record.prototype.fields, fi = f.items, fl = f.length;
<i>// Generate extraction functions <b>for</b> the totalProperty, the root, the id, and <b>for</b> each field</i>
<b>if</b> (!<b>this</b>.ef) {
<b>if</b>(s.totalProperty) {
<b>this</b>.getTotal = <b>this</b>.getJsonAccessor(s.totalProperty);
}
<b>if</b>(s.successProperty) {
<b>this</b>.getSuccess = <b>this</b>.getJsonAccessor(s.successProperty);
}
<b>this</b>.getRoot = s.root ? <b>this</b>.getJsonAccessor(s.root) : <b>function</b>(p){<b>return</b> p;};
<b>if</b> (s.id) {
<b>var</b> g = <b>this</b>.getJsonAccessor(s.id);
<b>this</b>.getId = <b>function</b>(rec) {
<b>var</b> r = g(rec);
<b>return</b> (r === undefined || r === &quot;&quot;) ? null : r;
};
} <b>else</b> {
<b>this</b>.getId = <b>function</b>(){<b>return</b> null;};
}
<b>this</b>.ef = [];
<b>for</b>(var i = 0; i &lt; fl; i++){
f = fi[i];
<b>var</b> map = (f.mapping !== undefined &amp;&amp; f.mapping !== null) ? f.mapping : f.name;
<b>this</b>.ef[i] = <b>this</b>.getJsonAccessor(map);
}
}
<b>var</b> root = <b>this</b>.getRoot(o), c = root.length, totalRecords = c, success = true;
<b>if</b>(s.totalProperty){
<b>var</b> v = parseInt(<b>this</b>.getTotal(o), 10);
<b>if</b>(!isNaN(v)){
totalRecords = v;
}
}
<b>if</b>(s.successProperty){
<b>var</b> v = <b>this</b>.getSuccess(o);
<b>if</b>(v === false || v === 'false'){
success = false;
}
}
<b>var</b> records = [];
<b>for</b>(var i = 0; i &lt; c; i++){
<b>var</b> n = root[i];
<b>var</b> values = {};
<b>var</b> id = <b>this</b>.getId(n);
<b>for</b>(var j = 0; j &lt; fl; j++){
f = fi[j];
<b>var</b> v = <b>this</b>.ef[j](n);
values[f.name] = f.convert((v !== undefined) ? v : f.defaultValue);
}
<b>var</b> record = <b>new</b> Record(values, id);
record.json = n;
records[i] = record;
}
<b>return</b> {
success : success,
records : records,
totalRecords : totalRecords
};
}
});</code></pre><hr><div style="font-size:10px;text-align:center;color:gray;">Ext - Copyright &copy; 2006-2007 Ext JS, LLC<br />All rights reserved.</div>
</body></html>