Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
ExtJS has some really nice support out of the box for converting JSON data to model objects. However, it only supports array-based associations, and doesn't support maps/associative arrays. The AssociativeReader - included here, along with two demo models and sample data - provides a way to do that.
/**
* A variant of the JSON reader. Instead of reading arrays, where each record in the array field
* has an 'id' property, it reads objects - aka associative arrays. The key of the entry will be the
* array.
*
* So where the JSON reader would like data like this:
* [ { id: '1', property: 'foo' }, { id: '2', property: 'bar' } ]
*
* the associative reader likes data like this:
* { '1': { property: 'foo' }, '2': { property: 'bar' } }
*/
Ext.define('Twasink.data.AssociativeReader', {
extend: 'Ext.data.reader.Json',
alias: 'reader.associative',
readRecords: function(data) {
// convert the associative array into a normal array.
var idProperty = 'id'; // should be a config value?
var arrayData = []
Ext.Object.each(data, function(key, value) {
var arrayEntry = {};
Ext.Object.merge(arrayEntry, value);
arrayEntry[idProperty] = key;
arrayData.push(arrayEntry);
});
return this.callParent( [ arrayData ]);
}
})
Ext.define('Twasink.model.Bar', {
extend: 'Ext.data.Model',
idProperty: 'id',
fields: [ 'baz', 'bux']
})
[
{ "id": "foo_1", "baz": "baz_1", "bux": "bux_1", "bar": {
"bar_1": { "baz": "bar_baz_1", "bux": "bar_bux_1" },
"bar_2": { "baz": "bar_baz_2", "bux": "bar_bux_2" }
}
},
{ "id": "foo_2", "baz": "baz_2", "bux": "bux_2", "bar": {
"bar_1": { "baz": "bar_baz_3", "bux": "bar_bux_3" },
"bar_2": { "baz": "bar_baz_4", "bux": "bar_bux_4" }
}
}
]
Ext.define('Twasink.model.Foo', {
extend: 'Ext.data.Model',
requires: [ 'Twasink.data.AssociativeReader', 'Twasink.model.Bar' ],
idProperty: 'id',
fields: [ 'baz', 'bux'],
hasMany: [ { model: 'Twasink.model.Bar', name: 'bars', associationKey: 'bar', reader: 'associative' }]
})
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment