I've injected some silly binding error in a large legacy project and am having trouble finding it.
This is the error output to the console:
warning: unable to bind to property 'length' on class 'String' (class
is not an IEventDispatcher)
I've tried stepping through with the debugger try to track down where this is happening but there are many thousands of lines of code and with event messaging, a very non-linear program execution.
Question: Is there any way to make Flash Builder break on a warning like this? If not, is there some other method, trick or hack for tracking this down?
This is caused by (wait for it...) trying to bind to a property that isn't marked as [Bindable]. In this case, you have a string variable whose length property is being used for data binding.
This is most likely caused by adding "myvar.length" as a property in the MXML tag for a component -- something like
<s:TextInput maxChars="{myInputString.length}" ...>
Flex will create the data binding for you automatically, but it doesn't realize at runtime that the property isn't Bindable - meaning, if there are changes to the property value the notification won't propagate to update the listeners.
Data binding uses mx.binding.PropertyWatcher to do the binding, and PropertyWatcher.updateParent is where the warning is output.
Related
I am in the progress of upgrading a legacy application from PrimeFaces 6.2 to 11.0.0 (which is the newest available with maven - https://mvnrepository.com/artifact/org.primefaces/primefaces). I have had to make a number of changes, including adding Object as the parameter for RowEditEvent and TreeNode objects (which are now generic) and changing instantiations of DefaultStreamedContent to use .builder(). Now, I am facing the following error whenever I try to run the application and navigate to certain pages:
"javax.faces.FacesException: Unable to automatically determine the lazy attribute. Either define the lazy attribute on the component or make sure the value attribute doesn't resolve to null."
It looks like an exception is being thrown rather than a warning as is noted in the conversation here: https://github.com/primefaces/primefaces/issues/8436. It also looks like it was fixed, but for version 12 (which is not on the maven central repository).
I am wondering what my options are, or what could be done about this. Should I go back to an older version?
As a workaround you could create an application factory which sets the lazy attribute to false.
See: https://primefaces.github.io/primefaces/11_0_0/#/core/globalattributes
Is it a lazy DataTable which uses LazyDataModel? If yes, just set lazy=true, otherwhise set lazy=false
Recently iam trying to update my angular project from 8 to 9. While updating i also updated wijmo from wijmo/wijmo to #grapecity/wijmo package as it supports IVY.
But after the completing the upgradation, i can able to compile the application but i am getting the following error at run time
global-error-handler.service.ts:43 Error: Uncaught (in promise): TypeError: (0 , t[n]) is not a function
TypeError: (0 , t[n]) is not a function
at backend.js:61
at Reflect.<anonymous> (backend.js:61)
at push../node_modules/#grapecity/wijmo.angular2.grid.detail/__ivy_ngcc__/index.js.__decorate (index.js:28)
at index.js:53
at Object../node_modules/#grapecity/wijmo.angular2.grid.detail/__ivy_ngcc__/index.js (index.js:53)
at __webpack_require__ (bootstrap:84)
I'd like to get some more info about this error. The quick thing to check is property initialization order. In Ivy, the properties are interpreted as they are specified in markup (previously wijmo controlled how they were interpreted). So you can break components by setting certain properties before others.
For example, if I tried to set the selectedIndex on a combobox BEFORE I set the data source, then the app would break at runtime because there are no items in the list to select yet.
More info here: https://www.grapecity.com/wijmo/docs/GettingStarted/Angular-Components#property-initialization-order-in-angular-9-ivy-and-higher
The next thing to check is component decorators (if you are inheriting our components). There are some breaking changes in decorators in Ivy.
For example, you might need to add {descendants: true} to ContentChildren queries.
Or you might need to add an #Injectable decorator to your class.
You can read more about breaking changes in Ivy and how to fix them here: https://angular.io/guide/ivy-compatibility-examples
But please feel free to contact us to work directly: wijmoexperts#grapecity.com
Looking for help writing an interface that has a property (or function) that returns an object typed as a "Form" (e.g. Access.Form as the return type).
Problem description:
The following simple example code returns a "User-defined type not defined" error if I attempt to compile the project.
I_TestInterface:
Public Property Get MyForm() as Form
End Property
cls_TestClass:
Implements I_TestInterface
Public Property Get I_TestInterface_MyForm() as Form
End Property
This is the only code/objects in a otherwise blank Access-2016 database and asking VBA to 'compile' produces a "User-defined type not defined" error. No lines are highlighted, it simply won't compile. Same occurs if replace 'Form' by "Access.Form"
My usecase is writing classes that wrap/hold a reference to a form internally - sometimes it is easiest to provide a reference to the underlying form so that consuming code can get at form properties without coding them all into the wrapper class.
Steps taken:
Lots of searches on 'user-defined type not defined' errors, in almost all cases this is due to a missing reference. Does not seem applicable since can create a standard module and happy to compile if write a function with a Form return type there. (*)
There was one previous SO thread on similar 'ambiguous' 'user-defined type not defined' error but I can't find it again and it wasn't specific to the 'Form' type in MS-Access
Have a clumsy workaround of providing property that returns an Object type that consuming code just has to cast to a Form (e.g. public property get MyFormAsObjectThatCanBeCastToForm() as Object).
(*). Possible clue? - if I just change the return types to object, the code still won't compile. I need to exit and use the 'de-compile' start up switch when relaunch Access. Then the above code with Object used as a return type is happily compiled.
Question / request:
Before I start re-installing Office, can others reproduce this?
Has anyone experienced this before? Developed a solution?
Thanks
PAHTDC
I have AdvancedDataGrid and I wanted to access dataProvider.getItemAt(i) in function in my view.
I'm not getting any errors nor warning and the code is compiling, but when I run this function I get this error:
Property getItemAt not found on mx.collections.HierarchicalCollectionView and there is no default value.
Why can't I do this? I saw some samples ane people was using this function.
This is how I call it:
var x:Object = _dg.dataProvider.getItemAt(i);
The AdvancedDataGrid's dataProvider is a generic object. That, basically, means the compiler will let any property/method access on it slide without issues.
The HierarchicalCollectionView does not have a getItemAt() method, which is why you get the runtime error. The Hierarchical collection, by nature, contains nested elements I'm not sure how you'd access a single element using a single index.
You probably want to use some form of getChildren() or getParentItem() method to get access to an individual node.
The places where you saw getItemAt() work were most likely using an ArrayCollection.
I'm using Flex SDK 4.6, very strange error occurs when i try to add spark checkbox on the stage:
var cb:CheckBox = new CheckBox();
optionsList.addElement(cb);
TypeError: Error #1009: Cannot access a property or method of a null
object reference. at
spark.skins.mobile::CheckBoxSkin/drawBackground()[E:\dev\4.y\frameworks\projects\mobiletheme\src\spark\skins\mobile\CheckBoxSkin.as:162]
at
spark.skins.mobile.supportClasses::MobileSkin/updateDisplayList()[E:\dev\4.y\frameworks\projects\mobiletheme\src\spark\skins\mobile\supportClasses\MobileSkin.as:313]
at
mx.core::UIComponent/validateDisplayList()[E:\dev\4.y\frameworks\projects\framework\src\mx\core\UIComponent.as:8999]
at
mx.managers::LayoutManager/validateDisplayList()[E:\dev\4.y\frameworks\projects\framework\src\mx\managers\LayoutManager.as:736]
at
mx.managers::LayoutManager/doPhasedInstantiation()[E:\dev\4.y\frameworks\projects\framework\src\mx\managers\LayoutManager.as:819]
at
mx.managers::LayoutManager/doPhasedInstantiationCallback()[E:\dev\4.y\frameworks\projects\framework\src\mx\managers\LayoutManager.as:1180]
When the chechbox is created in MXML there are no problems, but I need to create multiple instances in AS and than add them to stage.
Anyone have any clue what I'm doing wrong?
I'm posting to clear up a misconception, which was in the comments, and I believe is the root of the error. To quote:
I checked when I add the checkbox on creationComplete it works, but in
my case the checkboxes are added AFTER creationComplete when
updateDisplayList is called.
updateDisplayList() is called, potentially, a lot during a component's lifecycle. It is called every time something on the screen needs to update itself. updateDisplayList() is called at least once before the creationComplete event is dispatched, however in some situations, with some components, it could be called more times.
The code you shared is taken a bit out of context, however as it is you will end up with a lot of checkboxes; because a new checkbox will be created after every iteration of updateDisplayList(). I strongly recommend you move your children creation to the createChildren() method instead of updateDisplayList().
Here is some documentation on the Spark Flex Component LifeCycle and some on MX Component LifeCycle.