I am facing an issue with my controllers refs and the returned object being invalid. And by invalid it returning me an object that says it has not been rendered even though i am in the process of using it.
In my controller I have a ref defined as the following.
refs : [ {
ref : 'selectDeltaView',
selector : '[itemId=selectDeltaView]'
}]
and later in my controller I access this view using the created accessor
this.getSelectDeltaView()
What is strange is that the first time this view is presented, inside of an Ext.Window it works just fine. However, on the second launch the view I get back is not rendered.
this.getSeletDeltaView().rendered === false
Reading the documentation over at Sencha it seems that this simply passes my selector to the Ext.ComponentQuery.query function. However, if I call Ext.ComponentQuery.query('[itemId=selectDeltaView]') I get an array with a single element of which rendered is true.
Am i missing something? Why is my controllers reference returning me invalid data.
Update
Some additional details not mentioned in the original post. My initial assumption was that my view was not being destroyed. However, I have log statements in my ondestory and beforedestory events and can confirm that on closing the window my view is being destroyed.
What is the most confusing is that if refs simply use Ext.ComponentQuery.query, why does Ext.ComponentQuery.query only return one view when the window is re-opened and it returns the correct view. I understand from the question below that refs will catch the view, but that view no longer exist.. or shouldn't.. If the view is destroyed, can I force the controller to clear its catch?
The controllers reference is cached after the first evaluation.
What happens is this:
You open your view a first time.
getSeletDeltaView() finds that view, and stores a reference to it in the reference lookup cache.
You close the view, but you do not destroy it completely.
You open the view a second time, but it is a different instance.
getSeletDeltaView() finds the first view, that is no longer rendered, but still exists, because it was not destroyed. You cannot use this reference, because it point to the wrong view.
Solution:
Make sure to destroy() your view, when you hide it. You can also use autoDestroy as a property. Usually, autoDestroy is true by default.
Related
I'm wrestling with the way angular watches arrays. I have the following markup:
<map name="theMap" center="{{mapInfo.center.toUrlValue()}}" zoom="{{mapInfo.zoom}}" on-dragend="dragEnd()" on-zoom_changed="zoomChanged()">
<marker ng-repeat="pin in pins() track by pin.iconKey()" position="{{pin.latitude}}, {{pin.longitude}}" title="{{pin.streetAddress}}" pinindex="{{$index}}" on-click="click()"
icon="{{pin.icon()}}"></marker>
</map>
Each individual pin returned by pins() has a number of properties, sub-properties, etc. One of those sub-properties controls the marker color. When that subproperty changes I want the UI to update.
Because ng-repeat appears to $watch based on simply changes to the collection it's not obvious how to achieve that. I thought that my tracking function, iconKey(), would do it because it returns a different value depending upon the subproperty's value. But that didn't work.
One other thing: the subproperty gets changed in the callback from an $interval that runs under a directive. I mention this because, in an earlier post, someone thought that there might be a context/scope problem.
However, even when I make the change in an event listener within the UI's controller (where the event is raised within the "success" clause of the $interval callback) it still doesn't work.
That's why I think the problem is just angular not noticing the change in iconKey(); it's acting like all it $watches for ng-repeat is the array's length. Which doesn't change when the subproperty changes.
Update
I've created a plunker to demonstrate the issue I'm facing. You can find it at http://plnkr.co/edit/50idft4qaxqw1CduYkOd
It's a cut down version of the app I'm building, but it contains the essential elements (e.g., a data context service to hold information about the map pins and an $interval service to toggle the subproperty of one of the pin array elements).
You start the update cycle by clicking Start in the menu bar (you may want to drag the map down slightly to put both pins into full view). It should toggle the color of each pin, alternatively, 5 times each, once every 2 seconds. It does this by toggling the value of the isDirty property of the pin object in a listener defined in the controller. The event is raised by the $interval service.
If you break on line 22 during the test cycle you'll see the pin's icon being returned. So something within angular is calling for the information...but the pin color doesn't change.
I look forward to someone quickly pointing out the bone-headed mistake that has nothing to do with any of my theories :). Apologies in advance for whatever blinders I'm wearing.
Update 2
After checking out the code snippet in the response I simplified my plnkr and demonstrated that angular is, in fact, updating the UI when a subproperty changes. So this appears to be a limitation or bug in ng-map.
What you are missing here is the concept of array and function your function pins() passes an array and that array is been bound with ng-repeat. But the brutal fact here is that no matter what that array is never changed, because you do not have ANY reference to that array hence the rg-repeat will always remain as is...
I'll suggest to try get the array be referenced two ways to do that
ng-init="pinsArray = pins()"
and second inside controller
$scope.pinsArray = $scope.pins()
then make changes to $scope.pinsArray inside controller
ng-repeat will be changed to
ng-repeat="pin in pinsArray"
also read about filters I am guessing that's what you where trying to do with "track by"
hope this helps..
Edit: different story with ngMap markers
seems like it doesn't watch sub-property.
so here's a work around
add following statement to you update the pinsArray after making changes to its properties.
pinsArray = angular.copy(pinsArray);
the solved plnkr example:
http://plnkr.co/edit/EnW1RjE9v47nDpynAZLK?p=preview
For some reason when getData uses angular resource to bring the data it is being called twice, causing the resource to do it REST request twice too <--- bad...
Any idea why and how to solve it?
Here a working testcase/plunker example that recreates this scenario (look at the browser console - "getData being called...." displayed twice ) b.t.w as you can see I'm not really using the resource to bring real data, just to demonstrate the scenario, In my real app I do use the resource to bring real data and its being called twice just like in this example,
Thanks ahead
After looking into the src of the ng-table I noticed the following
$scope.$watch('params.$params', function(params) {
$scope.params.settings().$scope = $scope;
$scope.params.reload();
}, true);
Which means that the tables calls it 'getData' on count/filter/group/groupBy/page/sorting
which explains the behavior I was seeing.
When you call params.count(...) you ask ng-table to refresh data as you change page size. That's why you have two get-data calls.
If you don't want to have paging, then remove calls params.count and params.total.
If you need paging, then set page size and do not change it in getData.
This happened to me with a weird reason. getData get called twice on init (first load) only. changing page or sorting didn't call getData twice. The reason was that at init the ng-table directive was hidden in the template file.
Thank #Alexander Vasilyev. I understood my problem as you said. I want to explain a litte more here. In fact, the object "params" is the object configuration the table ng-table, then if "params" changed (ex: count or a property of the object), ng-table will invoke function getData() to refresh table.
In my case, I want to get information in the object "params" and change it but I dont want to refresh ng-table. I did it by cloning object "params" et work his object copied. Clone the object in JS with jQuery :
var resultParams = jQuery.extend(true, {}, params.$params);
And then, I will work on the object resultParams instead of "params" original.
I am able to mask() then unmask() a chart before and after it's rendered with : chart.mask() then chart.unmask().
But I want to add a loading message while it's masked, how can I do it? I'm using Extjs 4.1 with MVC.
Ext.Component (from which chart inherits) and Ext.dom.Element both have a mask method. But Ext.dom.Element's one accepts a msg argument.
That means you can achieve what you want with this kind of code:
chart.el.mask('My message');
Now there are a couple more things to take into account.
The most important is to ensure that the element is defined before calling its mask method. In effect, due to possible load delays or render deferrings, it might happen that some events or methods are called on components that have been destroyed or not yet rendered.
The second thing is that with this method, you won't have the loading CSS class by default. You can pass it as the second argument to mask if you want it; the class is 'x-mask-loading'.
With all that, the code should rather look like this:
var maskEl = chart.getMaskTarget() // this one's marked as private... maybe we shouldn't use it
|| chart.getEl();
if (maskEl) {
maskEl.mask("Loading...", Ext.baseCSSPrefix + 'mask-loading');
}
Unmask similarly. The check that the element still exists will be even more important there, because the chance that the component has been destroyed (e.g. window or tab closed) before the load is done is even greater.
I am using the XPages Mobile Controls with an Object data source (Java Class which is NOT a managed bean) tied to View scope on a second app page. I have resetContent on the second page set to true. So I would have assumed the Object Data Source would be destroyed and recreated every time I transitioned to the second page.
When I transition to the second page the first time, the createObject() method is invoked as expected. If I transition to the second page using a button AND set forceFullRefresh to true the createObject() method is invoked. If, however I have a Rounded List Item with a moveTo specified for the second page the createObject() method does not get invoked. Instead the object remains set to the last value it was using when that application page was last accessed.
Is there a way to force the createObject() method to be invoked every time I transition to the page?
Another way is to call the refresh method of the datasource in SSJS.
Assumning you have only one datasource on the page, you can access the ObjectDataSource from the view:
var ods:com.ibm.xsp.extlib.model.ObjectDataSource = view.getData().get(0);
ods.refresh()
This executes the createObject method binding and reinstantiate the datasource.
The solution turned out to be to move the object data source from view scope to request scope. This is possible because I do not have the need for any partial refreshes on that page until the details are ready to be submitted.
I'd just like to understand the decisions behind Backbone.Marionette's view regarding UI elements.
When instantiating a Marionette.View on an existing DOM element, like this:
view = new Marionette.ItemView({
el: "#element",
ui : {
whatever : "#whatever"
}
});
I am able to access view.$el, the jquery selector inside view.initialize, so far so good.
However, when I try to access view.ui.whatever, I only have access to the selector, ie the string "#whatever" instead of the actual $("#whatever") jquery selector.
The reason for this is because Marionette.View.bindUIElements() is only called on render and not before initialize.
I would like to know if you think this behaviour is logic and why?
I am only asking in the case of attaching of the view to an existing el, if the view is created with a template, I do understand why the binding is in render().
Attaching a view to an existing element is the exception. The normal view lifecycle involves calling render, and without doing that there would be nothing for the UI elements to bind to.
Just call this.bindUIElements() in your initialize method when you need to attach a view to an existing element.
When I am working with Marionette, I put the code that has to access the ui elements inside the onShow method. This event is fired after the dom is ready and the elements are ready to be manipulated. Inside this method, your ui.whatever will now be pointing to an element and not a string.
I think you have that problem because you have to access to the jQuery element with
this.ui.whatever
Because "this" is already a view instance.
See: http://marionettejs.com/docs/v2.4.4/marionette.itemview.html#organizing-ui-elements