I am using EmberJS and I am trying to setup the dependency on a computed property. A visitor can contain multiple tickets (an array), and I have access to an object containing an array of visitors. This is my computed property. How can the property be recomputed when a ticket is added to any of the visitors in the visitors array?
App.AttendanceController = App.SlideBaseController.extend
eligibleVisitors:
(->
return #getElegibleVisitors()
).property('App.state.session.visitors.#each.type')
allEligibleVisitorsAttending:
(->
return _.all #getElegibleVisitors(), (visitor)->
return visitor.tickets.length > 0 and _.any visitor.tickets, (ticket)->
return ticket.EventID is content.Event.ID
).property('App.state.session.visitors.tickets')
getElegibleVisitors:->
return _.filter App.state.session.visitors, (visitor)->
return visitor.type isnt App.VisitorTypes['Infant']
Something like this should work:
.property('App.state.session.visitors.#each.tickets.#each')
Updates when any ticket is added to any visitor.
AFAIK this is not possible right now and won't be for Ember 1.0. See here: https://github.com/emberjs/ember.js/issues/541
Nested #each properties don't trigger observers correctly.
I faced a similar problem (nested tree structure) -- I got around it by having each child node have a reference property to the parent node, and then adding
Node = Ember.Object.extend
nodeParent: null # to point at parent
nodeChanged: (->
#get('nodeParent')?.notifyPropertyChange 'notifier'
).observes 'various', 'properties
I used 'notifier' as a general key that other properties on the parent can bind to; when things in the child change, it causes a property change on the parent.notifier, which will in turn trigger other properties you want.
This is a hacky work around. Plus side is that it works, downside is you have to keep track of the child-parent relationship; i.e., for you, each Ticket needs to a reference to its Visitor
Related
I have a model written using Entity Framework Code First called Project.
In my UI, there is a page called ProjectEdit as shown in the image below. As seen in the image below, Customer and BOMs are Lookup Edit.
I'm trying to load Customer and BOMs to Lookup Edit but it's not working. Below is my code.
//New
if (entity == null)
{
Entity = new Project();
}
//Edit
else
{
ProjectCodeTextEdit.DataBindings.Add("EditValue", entity, "ProjectCode");
DescriptionTextEdit.DataBindings.Add("EditValue", entity, "Description");
CustomerLookUpEdit.DataBindings.Add("EditValue", entity, "CustomerId");
BOMsLookUpEdit.DataBindings.Add("EditValue", entity, "BOMs");
}
Below is my LookUpEdit Properties.
Generally LookUpEdit object's data binding is not implemented the same way as a TextEdit object's. While in TextEdits's case you just need to assign the variable value to EditValue property (I suppose your TextEdits binding work fine, isn't it?), with LookUp Edit you should assign variables to ValueMember and a DisplayMember properties of the object. That is why we usually display data rows with LookUpEdit objects, where ValueMember is the identification field of the row and DisplayMember is the field of the row whose value you wish to be displayed.
In your case you should be more clear about what you wish to display in your lookupedits. Each Project instance has one Customer property and many BOMs, right? So CustomerLookUpEdit will show one record and BOMsLookUpEdit a list of values according to the Project object that was chosen for edit, correct? I suppose that both your Customer and BOM classes have some kind of ID property and description property of their own. In this case you should bind these values to the LookUpEdits. eg. in your initialization function code add these lines
CustomerLookUpEdit.Properties.DataSource = entity.Customer;
CustomerLookUpEdit.Properties.ValueMember = "someCustomerIDpropertyName" ;
CustomerLookUpEdit.Properties.DisplayMember = "someCustomerDescriptionpropertyName";
BOMsLookUpEdit.Properties.DataSource = entity.BOMs;
BOMsLookUpEdit.Properties.ValueMember = "someBOMIDpropertyName" ;
BOMsLookUpEdit.Properties.DisplayMember = "someBOMDescriptionpropertyName" ;
You can read more in this topic https://documentation.devexpress.com/#WindowsForms/clsDevExpressXtraEditorsLookUpEdittopic
When we are adding entities to a List, we have to take care of our DataSource if is a DBContext or a DBSet, each one has implications in the compiler, that was your case, in this case you had to especify your DataSource like a DBSet and get the Entities
Add<TEntity>(TEntity entity)
The type parameter omitted is posible because the compiler will infer it.
I get an object from within an array in my model (a JSONmodel type) which is
{
"task": [
{
"dbid": 465,
"bk_cnt": 11,
}, {
"dbid": 472,
"bk_cnt": 16,
}
]
}
I bind this model to a table and connect the bk_cnt up to an objectNumber in a cell. No problem so far.
In code I want to change the value of the first bk_cnt value from 11 to 20 on press of a button. Inside the event I have:
var model = this.getView().getModel() // get the model
var tasks = model.getProperty("/task"); // get as a JS object
tasks[0].bk_cnt = 20 // update the model...will it update the view?
// model.refresh() // it will if this is uncommented.
Problem: Though it is bound to the view, the displayed value of bk_cnt does not change. if I add model.refresh() it does. This code is extracted from a larger section and one of the larger features is sorting by column click. When I click a column to re-sort (no change to the model), the value 20 appears.
What gives?
Musings: I have read that the model.getProprty() function returns a javascript object with a live reference back to the model, and that a change to the value of the object will automatically be reflected in the view for any bound controls. Does this statement fall down on array attributes ?
EDIT: Still feeling around the issue I find that
model.setProperty("/task/0/bk_cnt", 20)
Does not require a model.refresh() to update the view. Not a total surprise as this command is directly acting through the model. This leaves me thinking that the 'live' object returned by getProperty() is only live when it is a primitive datatype like a string or integer, but not for a JS object. Or am I missing something ?
EDIT 2: #Ash points out in his answer that there is a further approach which is to access the JS object from the model property, set whatever attributes need to be updated in the JS object, then replace that into the model, e.g.
var tasks = model.getProperty("/task");
tasks[0].bk_cnt = 20
model.setProperty('/task', tasks)
Second edit done to complete the trio of approaches for future readers.
The Model object is an abstraction layer ON TOP of a javascript object. There is no way that a change within an object is notified anywhere. You need to explicitly trigger the notifications through model.refresh() or model.setProperty().
So both of your solutions are valid, another one (which I favor) would be
var tasks = model.getProperty("/task");
tasks[0].bk_cnt = 20
model.setProperty('/task', tasks)
But this actually depends on how you bind your model to your UI objects :)
I'm trying to sync a dataview (explorer window) with a tree (directory tree).
When I click on an element on my dataview, I'd like the same node gets selected on the tree
The problem is that using the
tree.getSelectionModel().select(index)
doesn't allow me to select the node by its internal id (the id I provided in my treestore), but only by the record index...
So I just can't sync both views...
There would be the solution of the expandPath(), but my treestore is fed by a relational database (id,name,parent_id etc..), so finding the full path is(or could be) a heavy load for the server (I'd like to avoid to have to provide any path...).
Basically I would like to be able to say "expand the node where the "id= " (or any other key/value of the treestore).
Is it possible ? Is there any workaround ?
Thank you for reading me !
The tree.getSelectionModel().select(record) function can accept a record instance instead of an index. I would do something like this:
var record = tree.getRootNode().findChild('id_name','record_id',true);
tree.getSelectionModel().select(record);
for more info on the findChild function, check out the NodeInterface docs here:
http://docs.sencha.com/ext-js/4-0/#/api/Ext.data.NodeInterface-method-findChild
you can also use selecteditemtree.data.id for this.
Sorry for the length, but a picture is worth 1000 words:
In ASP.NET MVC 2, the input form field "name" attribute must contain exactly the syntax below that you would use to reference the object in C# in order to bind it back to the object upon post back. That said, if you have an object like the following where it contains multiple Orders having multiple OrderLines, the names would look and work well like this (case sensitive):
This works:
Order[0].id
Order[0].orderDate
Order[0].Customer.name
Order[0].Customer.Address
Order[0].OrderLine[0].itemID // first order line
Order[0].OrderLine[0].description
Order[0].OrderLine[0].qty
Order[0].OrderLine[0].price
Order[0].OrderLine[1].itemID // second order line, same names
Order[0].OrderLine[1].description
Order[0].OrderLine[1].qty
Order[0].OrderLine[1].price
However we want to add order lines and remove order lines at the client browser. Apparently, the indexes must start at zero and contain every consecutive index number to N.
The black belt ninja Phil Haack's blog entry here explains how to remove the [0] index, have duplicate names, and let MVC auto-enumerate duplicate names with the [0] notation. However, I have failed to get this to bind back using a nested object:
This fails:
Order.id // Duplicate names should enumerate at 0 .. N
Order.orderDate
Order.Customer.name
Order.Customer.Address
Order.OrderLine.itemID // And likewise for nested properties?
Order.OrderLine.description
Order.OrderLine.qty
Order.OrderLine.price
Order.OrderLine.itemID
Order.OrderLine.description
Order.OrderLine.qty
Order.OrderLine.price
I haven't found any advice out there yet that describes how this works for binding back nested ViewModels on post. Any links to existing code examples or strict examples on the exact names necessary to do nested binding with ILists?
Steve Sanderson has code that does this sort of thing here, but we cannot seem to get this to bind back to nested objects. Anything not having the [0]..[n] AND being consecutive in numbering simply drops off of the return object.
Any ideas?
We found a work around, by using the following:
Html.EditorFor(m => m, "ViewNameToUse", "FieldPrefix")
Where FieldPrefix is the "object[0]". This is hardly ideal, but it certainly works pretty well. It's simple and elegant.
I'm using Symfony 1.2 with Doctrine. I have a Place model with translations in two languages. This Place model has also a nested set behaviour.
I'm having problems now creating a new place that belongs to another node. I've tried two options but both of them fail:
1 option
$this->mergeForm(new PlaceTranslationForm($this->object->Translation[$lang->getCurrentCulture()]));
If I merge the form, what happens is that the value of the place_id field id an array. I suppose is because it is waiting a real object with an id. If I try to set place_id='' there is another error.
2 option
$this->mergeI18n(array($lang->getCurrentCulture()));
public function mergeI18n($cultures, $decorator = null)
{
if (!$this->isI18n())
{
throw new sfException(sprintf('The model "%s" is not internationalized.', $this->getModelName()));
}
$class = $this->getI18nFormClass();
foreach ($cultures as $culture)
{
$i18nObject = $this->object->Translation[$culture];
$i18n = new $class($i18nObject);
unset($i18n['id']);
$i18n->widgetSchema['lang'] = new sfWidgetFormInputHidden();
$this->mergeForm($i18n); // pass $culture too
}
}
Now the error is:
Couldn't hydrate. Found non-unique key mapping named 'lang'.
Looking at the sql, the id is not defined; so it can't be a duplicate record (I have a unique key (id, lang))
Any idea of what can be happening?
thanks!
It looks like the issues you are having are related to embedding forms within each other, which can be tricky. You will likely need to do things in the updateObject/bind methods of the parent form to get it to pass its values correctly to its child forms.
This article is worth a read:
http://www.blogs.uni-osnabrueck.de/rotapken/2009/03/13/symfony-merge-embedded-form/comment-page-1/
It gives some good info on how embedding (and mergeing) forms work. The technique the article uses will probably work for you, but I've not used I18n in sf before, so it may well be that there is a more elegant solution built in?