I'm new to Ractive.js and using "magic mode" so that updates to my JS objects automatically trigger updates to my UI. Everything is working great except that I have some properties which are added to my bound objects after my Ractive instances are rendered. This means that Ractive doesn't see changes to those properties, so the "magic" doesn't work for them.
As a workaround, I've found that I can just initialize those properties with 'empty' values before passing them to Ractive, but it feels a little unnatural.
Is there a preferred way to inform Ractive that I've added a new property to an object that it should start tracking?
My experince is that you can du that in 2 ways.
The first is the one you describe in your post.
The second is to "add" the property through the template that you use to render the object.
What ractive actually do when you set magic mode to true is "wrapping/replacing" your field with a property wich monitores the changes to the field.
I have had som issues using magicmode when i use Object.DefineProperty on my data objcect. (stuff get called twice)
I would go for soulution 1, and define all fields ahead of time.
Also be aware of setting your field(wich is actually now a property replaced by ractive) to something that is not a valuetype as that will again overwrite the property and mess up magicmode.
Related
I'm trying to better understand the fundamentals of A-Frame.
I understand how to use the getAttribute() and setAttribute() methods for
accessing component data. However I don't understand why we use them instead of just accessing the components attributes using dot notation.
A lot of people use something like:
document.querySelector("#myText").getAttribute('text').value
Why not use:
document.querySelector("#myText").components['text'].data.value
Is there something wrong with using that second way? What are the pitfalls? In my experiments I have experienced both ways returning "undefined" due to the code running before the scene is finished loading, but I have learned how to avoid that using the "loaded" event.
As you can see at this glitch example (https://glitch.com/~text-hierarchy) I've successfully printed data to the console using both ways.
Part of the standard
Both getAttribute(prop) and setAttribute(prop, value) are used to get/set attributes of any other DOM elements. MDN links here (get, set)
Compatible with aframe components
If you have a update() function in your a-frame component, setAttribute() calls it, notyfing, that a property of a component has changed.
It's not mandatory, it's even faster to modify some properties directly, but it has risks, like undefined behavior if a developer uses update() to monitor changes.
I want to change my rehosted activities look to:
Already tried ActivityDesignerTheme
Need to do it without using WorkflowViewElement because I don't want to lose it's behaviors (breakpoint, expanding).
If it's not possible, is there a way to change ActivityDesigner header background color?
#Will
I was annoyed too by the default behavior of the ActivityDesigner header when editing the DisplayName (especially the part where it positions the caret at the beginning of the string). I used Reflector to peek (System.Activities.Presentation.dll) at the implementation and I noticed that some of this behavior is defined in OnApplyTemplate. By just overriding this method in my custom designer class and NOT calling base.OnApplyTemplate(), I was able to make the DisplayName read only in the header (in my case that was all I needed, but I think one can play with some custom event handlers in there and tweak the behavior).
#Davi Fiamenghi
Digging around some more with Reflector in the same assembly, I found the controls used in OnApplyTemplate defined under system/activities/presentation/workflowelementdesignerdefaulttemplate.baml (System.Activities.Presentation.g.resources). That seems to be the default control template used for ActivityDesigner (<ControlTemplate x:Key="WorkflowElementDesignerDefaultTemplate" x:Uid="ControlTemplate_1" ControlTemplate.TargetType="{x:Type swd:ActivityDesigner}">). I guess one way to change the header color would be to try to "re-create" this template in your application and set it explicitly in your custom activity designer. Of course it's more involved than just copying it, since it appears to be referencing other resources defined in that assembly.
Hope this helps.
I am new to Flex and trying to modify some existing code. I am trying to It uses and AdvancedDataGrid. In the click event, the ListEvent is passed in, and the code is able to access properties such as event.itemRenderer.data.feature.
I would like to check whether the user has clicked on a parent (group) record or the child record; at runtime, I can see that the property I want to access is event.itemRenderer.listData.hasChildren. However, the listData property of itemRenderer does not show up in intellisense, and when I try to access that at design time, the project will not build because of the error "Access of possibly undefined property listData". But the property .data.feature doesn't show up in intellisense at design time either, and that builds and runs just fine.
What do I need to do to access event.itemRenderer.listData without throwing errors when I build the project? Do I need to capture a different event, or cast the event object or one of its properties into another object that will have the properties I need at runtime (I've investigated these options but cannot find info on how to do that).
Many thanks for any insight.
You probably have to perform a cast using IDropInListItemRenderer and AdvancedDataGridListData. Something like this:
((event.itemRenderer as IDropInListItemRenderer).listData as AdvancedDataGridListData).hasChildren
I have a web application with a form that has disabled fields in it. It allows a "Save As" function which basically means the settings can be copied into a new configuration (without being modified) and in the new configuration they can be changed to something else. The problem I am running into with this is that since the fields are disabled, they are not getting posted through and do not appear in the context object on the server side.
When I removed the logic to disable the fields, that part works fine. So the remaining problem is, how to "disable" the fields (not allow any change of the data in any of the entry fields) without really "disabling" them (so that the data gets posted through when saving)?
I was originally looking for a way to do this in CSS but not sure if it exists. The best solution is of course, the simplest one. Thanks in advance!
(Note: by 'disabled' I mean "The textboxes display but none of the text inside of them can be modified at all". It does not matter to me whether the cursor appears when you click inside it, though if I had a preference it would be no cursor...)
http://www.w3schools.com/TAGS/att_input_readonly.asp
readonly attribute is what you want.
i would suggest that instead of using the non-updateable field values from the page's inputs, you retrieve the original object from the DB and copy them from there. It's pretty trivial using something like Firebug to modify the contents of the page whose form will be posted back to modify the values, even if they are marked as readonly. Since you really want the values from the original, I would simply reget the object and copy them. Then you don't need to worry about whether the original (and non-updateable) properties get posted back at all.
Flex 3 question:
I trying here to avoid having to bind resources to all my components labels ( ie a button) and find a way to have this automated.
Problem:
It corrupts the layout in design mode to bind directly in the mxml label="{resourceManager.getString('myResources', 'submit')}" and makes the design view useless. but when declaring bindings elsewhere, in actionScript or via a bind tag, it is counter productive and prone to many errors and miss.
Proposition:
I would like to create my own button that automatically invoke resources to localize a button label. So the author puts "Submit" in the mxml description of my button, and when running it would take the value of the label ie "submit" and use resourceManager.getString('myResources', 'submit').
but I can't find the way to override the set label function, Is it possible if yes how? else how can I go about it?
Maybe I am missing an essential process here that would make the use of resources more elegant, as well as how to override such thing as a button's label.
Thanks for your advices.
Create a component called MyButton, extending Button. Then use this:
override public function set label(value:String):void {
super.label = resourceManager.getString('myResources', value) || value;
}
Assuming the resource manager returns "null" or "undefined" this will work, and will only replace the value if it exists in "myResources".
If you don't want to override every component you need to do this with, then you can add a FlexEvent.CREATION_COMPLETE event on every component. Then use a single generic function to do your label localization.