Not giving Parent data from Child in association in extjs - extjs

Question

Hope you are doing good.
I am new in extjs4 and working on sample example of association.
I have 2 different class User and Diploma
In relation, I have defined.
User hasMany Diplomas, and Diplomas belongsTo User
My models are as belows
User.js
Ext.define('MyApp.model.User', {
extend : 'Ext.data.Model',
idProperty : 'userId',
fields : [{
name : 'userId',
type : 'integer'
}, {
name : 'userName',
type : 'string',
}],
hasMany : {
model : 'MyApp.model.Diploma',
name : 'diplomas',
},
});
Diploma.js
Ext.define('MyApp.model.Diploma', {
extend : 'Ext.data.Model',
idProperty : 'diplomaId',
fields : [{
name : 'diplomaId',
type : 'integer'
}, {
name : 'diplomaName',
type : 'string',
}, {
name : 'userId',
type : 'integer'
}],
associations : [{
model : 'MyApp.model.User',
name : 'user',
type : 'belongsTo'
}]
});
=====================
My Stores are as below.========================
Diploma.js
Ext.define('MyApp.store.Diploma', {
extend : 'Ext.data.Store',
model : 'MyApp.model.Diploma',
autoLoad : true,
listeners : {
'load' : {
fn : function(store, records, success, operation) {
console.log('Diplomas are loaded');
}
}
}
});
User.js
Ext.define('MyApp.store.User', {
extend : 'Ext.data.Store',
model : 'MyApp.model.User',
requires:['Ext.data.proxy.LocalStorage'],
autoLoad : true,
listeners : {
'load' : {
fn : function(store, records, success, operation) {
console.log('User is loaded');
}
}
},
data : [{
userId : 1,
userName : 'Rishabh Shah',
diplomas:{
userId : 1,
diplomaId:1,
diplomaName:'IT'
}
}, {
userId : 2,
userName : 'Rakesh Shah',
diplomas:{
userId : 2,
diplomaId:2,
diplomaName:'CE'
}
}, {
userId : 3,
userName : 'Rashmin Shah'
}],
proxy:{
type:'memory',
reader:{
root:'data'
}
}
});
I can get diploma from user like that and can get result
Ext.getStore("User").getAt(0).diplomasStore.getAt(0)
but, when I try to do like
Ext.getStrore("Diploma") or Ext.getStrore("Diploma").getAt(0)
I don't get anything. items contains nothing...
How can I get user from diploma.
and One more thing....if I don't write proxy in my Diploma model..
it gives me an error like this..
Ext.data.proxy.Server.buildUrl(): You are using a ServerProxy but have not supplied it with a url.
Please guide me.
Thanks.
Thanks for your reply..#john..I can get diplomas from User..
I wanted to get user from diplomas...I tried it myself..and found solution...
I will have following json.
[
{
"depId": 1,
"depName": "CE",
"employees": [
{
"empId": 1,
"firstName": "Rishabh",
"lastName": "Shah"
}, {
"empId": 2,
"firstName": "Smit",
"lastName": "Patel"
}
]
}, {
"depId": 2,
"depName": "IT",
"employees": [
{
"empId": 1,
"firstName": "Parag",
"lastName": "Raval"
}, {
"empId": 2,
"firstName": "Rakesh",
"lastName": "Prajapati"
}
]
}, {
"depId": 3,
"depName": "EE",
"employees": [
{
"empId": 1,
"firstName": "Parag EE",
"lastName": "Raval EE"
}, {
"empId": 2,
"firstName": "Rakesh EE",
"lastName": "Prajapati EE"
}
]
}, {
"depId": 4,
"depName": "EC",
"employees": [
{
"empId": 1,
"firstName": "Parag EC",
"lastName": "Raval EC"
}, {
"empId": 2,
"firstName": "Rakesh EC",
"lastName": "Prajapati EC"
}
]
}, {
"depId": 5,
"depName": "Chemial E",
"employees": [
{
"empId": 1,
"firstName": "Parag",
"lastName": "Raval"
}, {
"empId": 2,
"firstName": "Rakesh",
"lastName": "Prajapati"
}
]
}, {
"depId": 6,
"depName": "ME",
"employees": [
{
"empId": 1,
"firstName": "Parag",
"lastName": "Raval"
}, {
"empId": 2,
"firstName": "Rakesh",
"lastName": "Prajapati"
}
]
}, {
"depId": 7,
"depName": "Civil Engineer",
"employees": [
{
"empId": 1,
"firstName": "Parag",
"lastName": "Raval"
}, {
"empId": 2,
"firstName": "Rakesh",
"lastName": "Prajapati"
}
]
}
]
and I will use model.getAssociatedData().user as per my requirement
where model is my record of child class and user is my parent class..
and I was using proxy in my Diploma Model which was not requierd....so, was getting
Ext.data.proxy.Server.buildUrl(): You are using a ServerProxy but have not supplied it with a url.
above mentioned error.
Thanks All ! :)

Answer 1

What exactly isn't working? Have you been able to use the magic methods e.g., User.diplomas()? As #VDP stated, the store created for the Association is a normal Ext.data.Store scoped to the set of data for the parent model (in this case, User). That is to say, if you have a User model with the id of 1, calling the method User.diplomas() will return a Ext.data.Store filtered to contain only Diploma's with a user_id of 1.
This is very important to understand! If you do not specify the foreignKey property in a hasMany association, it will default to the lowercased name of the owner model plus "_id", You should amend your User model's hasMany association as so:
Ext.define('MyApp.model.User', {
/** Model Definition */
hasMany : {
model : 'MyApp.model.Diploma',
name : 'diplomas',
foreignKey : userId /** This is what you're missing */
}
});
Perhaps you will find this blog post useful? http://extjs-tutorials.blogspot.com/2012/05/extjs-hasmany-relationships-rules.html
Some important tips from the blog post (in case the link dies at some point)
Always put your Proxies in your Models, not your Stores, unless you
have a very good reason not to *
Always require your child models if using them in hasMany
relationships. **
Always use foreignKey if you want to load the children at will
Always use associationKey if you return the children in the same
response as the parent
You can use both foreignKey and associationKey if you like
Always name your hasMany relationships
Always use fully qualified model names in your hasMany relationship
Consider giving the reader root a meaningful name (other than "data")
The child model does not need a belongsTo relationship for the
hasMany to work
*The store will inherit its model's proxy, and you can always override it
**To make it easy, and avoid potential circular references, you can require them in app.js
Credit: Neil McGuigan (http://www.blogger.com/profile/14122981831780837323)