Im working on a piece of code using DevExpress XAF, I noticed that if im using the event OnSaving that the code executes 2 times, how can i prevent that
protected override void OnSaving()
{
if (PrestamoP != null)
{
PrestamoP.Prestado -= Monto;
PrestamoP.Save();
}
else if (PrestamoG != null)
{
PrestamoG.Prestado -= Monto;
PrestamoG.Save();
}
base.OnSaving();
}
XPO does not guarantee that the OnSaving method is called once. See the corresponding note in the XPO Best Practices article.
I can see that you are changing the PrestamoP.Prestado property based on the value of the Monto property. This code is fine if you execute it only once and only when the Monto property is specified for the first time. This code is not fine if you:
Save this object without changing the Monto property;
Update the early specified Monto value.
So, it appears that a more complex logic is required for the PrestamoG.Prestado property. First, I would move it to the Monto property setter and take the previous value into account (do not forget to check the IsLoading property in this case). Second, I would consider calculating the Prestado value dynamically instead of storing its value. This will allow you to resolve issues with the duplicate business logic execution. See an example here: How to: Calculate a Property Value Based on Values from a Detail Collection.
I can offer different methods for CRUD functions on onSaving method.
IsNewObject, IsDeleted.
// insert
if (Session.IsNewObject(this))
{
a = new a(Session);
a.CreateReferencedProperties(this);
}
// delete
else if (IsDeleted)
{
a= Session.FindObject<A>(PersistentCriteriaEvaluationBehavior.InTransaction, CriteriaOperator.Parse("A=?", this));
if (a!= null)
a.Delete();
}
// update
else
{
a= Session.FindObject<A>(PersistentCriteriaEvaluationBehavior.InTransaction, CriteriaOperator.Parse("A=?", this));
if (a!= null)
a.CreateReferencedProperties(this);
}
You can use the code below to prevent xaf from entering on saving twice.
base.OnSaving();
SessionObjectLayer sessionObjectLayer = this.Session.ObjectLayer as SessionObjectLayer;
if (sessionObjectLayer == null || sessionObjectLayer.ParentSession == null)
{
//Enter only once
}
Related
I encountered a problem in the development, requesting a new purchase request line of a purchase with a legal person with a default value of empty
I tried a variety of methods, the default value can not be overriden.
The following is my code.
[ExtensionOf(formDataSourceStr(PurchReqTable, PurchReqLine))]
final class IWS_PurchReqTable_FDS_Extension
{
public void initValue()
{
next initValue();
//ttsbegin;
PurchReqLine purchReqLine = this.cursor();
purchReqLine.BuyingLegalEntity = 0;
purchReqLine.modifiedField(fieldNum(PurchReqLine,BuyingLegalEntity));
this.rereadReferenceDataSources(); //Refresh value
this.reread();
this.research(1);
FormReferenceGroupControl BuyingLegalEntity = this.formRun().design().controlName(formControlStr(PurchReqTable, PurchReqLine_BuyingLegalEntity));
FormStringControl BuyingLegalEntity_DataArea = this.formRun().design().controlName(formControlStr(PurchReqTable, PurchReqLine_BuyingLegalEntity_DataArea));
BuyingLegalEntity.value(0);
BuyingLegalEntity.resolveChanges();
BuyingLegalEntity.referenceDataSource().research(1);
BuyingLegalEntity.modified();
//BuyingLegalEntity_DataArea.text('');
//BuyingLegalEntity_DataArea.modified();
purchReqLine.BuyingLegalEntity = 0;
purchReqLine.modifiedField(fieldNum(PurchReqLine,BuyingLegalEntity));
//purchReqLine.update();
//purchReqLine.insert();
//this.rereadReferenceDataSources();
//this.refresh();
//this.reread();
//this.resetLine();
//ttscommit;
}
//End
}
It is not totally clear to me what you are trying to do.
Most values are "born" zero or blank and if that is not the case for this field, something else is setting the field, maybe after your code in initValue is called. The cross reference may be of good value here to find the code that references the field.
First of, you should definitely not reference the controls, also calling modifiedField and research from here is a total no-go.
For a start try this:
public void initValue()
{
next initValue();
purchReqLine.BuyingLegalEntity = 0;
}
It simply sets the field to zero. Do not worry about the field control, it will be rendered from the buffer value after the call to initValue.
If that does not solve your problem, something else is setting the field. You can set a breakpoint here, then follow to code until the field is set. Also add the value to the watch list, maybe do conditional debugging.
If another extension for this datasource exist it may override your behaviour as the execution order of extensions is arbitrary.
Can't seem to find an answer to this issue easily.
Default values for fields you want to display and allow editing, the best place seems to be to set the widget.value in a draft record, so default date widget.value = new Date(), etc.
How do I reference a dropdown where the dropdown is a related table lookup, e.g., a list of Properties where the bindings are #datasources.Property.Items for the options and #datasource.Item.Property for the value.
If I do console.log(widget.value); I get object Object, which is what I would expect because it is of type object. But how can I set (and retrieve) its value?
Help appreciated.
I tested this for a similar situation in my own application. Do note that there is a minimal delay before the value in the dropdown actually populates. I'm not sure what your alternative solution could be due to the reason stated in my last comment above. I might suggest setting this in your form model onBeforeCreate event instead, but then you would loose the ability to change the relation in the form itself so that might not work for you.
Dropdown widget onAttach event:
var datasource = app.datasources.Property;
if(!datasource.loaded) {
datasource.load(function() {
var index = datasource.items.map(function(i){return i.Status;}).indexOf('Open');
if(index !== -1) {
widget.value = datasource.items[index];
}
});
} else {
var index = datasource.items.map(function(i){return i.Status;}).indexOf('Open');
if(index !== -1) {
widget.value = datasource.items[index];
}
}
We are rying to use WF with multiple tracking participants which essentially listen to different queries - one for activity states, one for custom tracknig records which are a subclass of CustomTrackingRecord.
The problem is that we can use both TrackingParticipants indivisually, but not together - we never get our subclass from CustomTrackingRecord but A CustomTrackingRecord.
If I put bopth queries into one TrackingParticipant and then handle everythign in one, both work perfectly (which indicates teh error is not where we throw them).
The code in question for the combined one is:
public WorkflowServiceTrackingParticipant ()
{
this.TrackingProfile = new TrackingProfile()
{
ActivityDefinitionId = "*",
ImplementationVisibility = ImplementationVisibility.All,
Name = "WorkflowServiceTrackingProfile",
Queries = {
new CustomTrackingQuery() { Name = "*", ActivityName = "*" },
new ActivityStateQuery() {
States = {
ActivityStates.Canceled,
ActivityStates.Closed,
ActivityStates.Executing,
ActivityStates.Faulted
}
},
}
};
}
When using two TrackingParticipants we have two TrackingProfile (with different names) that each have one of the queries.
in the track method, when using both separate, the lines:
protected override void Track(TrackingRecord record, TimeSpan timeout)
{
Console.WriteLine("*** ActivityTracking: " + record.GetType());
if (record is ActivityBasedTrackingRecord)
{
System.Diagnostics.Debugger.Break();
}
never result in the debugger hitting, when using only the one to track our CustomTrackingRecord subclass (ActivityBasedTrackingRecord) then it works.
Anyone else knows about this? For now we have combined both TrackingParticipants into one, but this has the bad side effect that we can not dynamically expand the logging possibilities, which we would love to. Is this a known issue with WWF somewhere?
Version used: 4.0 Sp1 Feature Update 1.
I guess I encounterad the exact same problem.
This problem occurs due to the restrictions of the extension mechanism. There can be only one instance per extension type per workflow instance (according to Microsoft's documentation). Interesting enough though, one can add multiple instances of the same type to one workflow's extensions which - in case of TrackingParticipant derivates - causes weird behavior, because only one of their tracking profiles is used for all participants of the respective type, but all their overrides of the Track method are getting invoked.
There is a (imho) ugly workaround to this: derive a new participant class from TrackingParticipant for each task (task1, task2, logging ...)
Regards,
Jacob
I think that this problem isn't caused by extension mechanism, since DerivedParticipant 1 and DerivedParticipant 2 are not the same type(WF internals just use polymorphism on the base class).
I was running on the same issue, my Derived1 was tracking records that weren't described in its profile.
Derived1.TrackingProfile.Name was "Foo" and Derived2.TrackingProfile.Name was null
I changed the name from null to "Bar" and it worked as expected.
Here is a WF internal reference code, describing how is the Profile selected
// System.Activities.Tracking.RuntimeTrackingProfile.RuntimeTrackingProfileCache
public RuntimeTrackingProfile GetRuntimeTrackingProfile(TrackingProfile profile, Activity rootElement)
{
RuntimeTrackingProfile runtimeTrackingProfile = null;
HybridCollection<RuntimeTrackingProfile> hybridCollection = null;
lock (this.cache)
{
if (!this.cache.TryGetValue(rootElement, out hybridCollection))
{
runtimeTrackingProfile = new RuntimeTrackingProfile(profile, rootElement);
hybridCollection = new HybridCollection<RuntimeTrackingProfile>();
hybridCollection.Add(runtimeTrackingProfile);
this.cache.Add(rootElement, hybridCollection);
}
else
{
ReadOnlyCollection<RuntimeTrackingProfile> readOnlyCollection = hybridCollection.AsReadOnly();
foreach (RuntimeTrackingProfile current in readOnlyCollection)
{
if (string.CompareOrdinal(profile.Name, current.associatedProfile.Name) == 0 && string.CompareOrdinal(profile.ActivityDefinitionId, current.associatedProfile.ActivityDefinitionId) == 0)
{
runtimeTrackingProfile = current;
break;
}
}
if (runtimeTrackingProfile == null)
{
runtimeTrackingProfile = new RuntimeTrackingProfile(profile, rootElement);
hybridCollection.Add(runtimeTrackingProfile);
}
}
}
return runtimeTrackingProfile;
}
I have a DropdownList that shows a list of providers & the Provider associated with that Patient must be selected.
The Dropdown list:
<s:DropDownList id="providerList"
width="80%"
fontSize="12"
fontWeight="bold"
selectionColor="white"
creationComplete="providerList_creationCompleteHandler(event)"
dataProvider="{model.practiceProviderList.practiceProviders}"/>
where practiceProviders is an ArrayCollection
The CreationCompleteHandler function:
protected function providerList_creationCompleteHandler(event:FlexEvent):void
{
var firstN:String;
var lastN:String;
var providerObj:Provider = new Provider();
if (model.patientDetails.patientDetail.patientProviders != null && model.patientDetails.patientDetail.patientProviders.length > 0)
{
firstN = patientDetailsModel.patientDetails.patientDetail.patientProviders.getItemAt(0).provider.providerName.firstName;
lastN = patientDetailsModel.patientDetails.patientDetail.patientProviders.getItemAt(0).provider.providerName.lastName;
for (var count:int = 0; count < patientDetailsModel.practiceProviderList.practiceProviders.length; ++count)
{
providerObj = patientDetailsModel.practiceProviderList.practiceProviders.getItemAt(count, 0).provider as Provider;
if (providerObj.providerName.firstName == firstN && providerObj.providerName.lastName == lastN)
{
this.providerList.selectedIndex = count;
}
}
}
}
The issue is when I go to this page the first time, the error is :
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at com.newwavetechnologies.modules::demographics/providerList_creationCompleteHandler()[C:\harish\flex\apps\workspace\dataCollection-flexUserInterface\src\com\newwavetechnologies\modules\demographics.mxml:166]
at com.newwavetechnologies.modules::demographics/__providerList_creationComplete()[C:\harish\flex\apps\workspace\dataCollection-flexUserInterface\src\com\newwavetechnologies\modules\demographics.mxml:359]
at flash.events::EventDispatcher/dispatchEventFunction()
at flash.events::EventDispatcher/dispatchEvent()
at mx.core::UIComponent/dispatchEvent()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\core\UIComponent.as:12266]
at mx.core::UIComponent/set initialized()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\core\UIComponent.as:1577]
at mx.managers::LayoutManager/doPhasedInstantiation()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\managers\LayoutManager.as:759]
at mx.managers::LayoutManager/doPhasedInstantiationCallback()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\managers\LayoutManager.as:1072]
where line 166 is:
if (providerObj.providerName.firstName == firstN && providerObj.providerName.lastName == lastN)
The providerObj is null the first time. But when hit back and come to the same page again, everything works fine and 1 of the providers in the list is selected correctly.
Probably I think the first time, the creationComplete handler method is called before the List is populated. The 2nd time when the call is made, the list is populated and the handler works fine. It would be great if someone can help me in this regard on how to go about this.
Thanks
Harish
It's hard to tell what's going on here, but the problem lies here:
providerObj = patientDetailsModel.practiceProviderList.practiceProviders.getItemAt(count, 0).provider as Provider;
There's a tonne of places in that line that Null pointer exceptions could occur.
Most likely - the practiceProvider returned at position count doesn't have a provider set. We can't see how this value is populated, but given this code works later, I'd say you've got a race condition happening - the data is being accessed before it's been set.
At very least, you should add a guardClause for this:
var practiceProviders:ArrayCollection = patientDetailsModel.practiceProviderList.practiceProviders;
for (var count:int = 0; count < practiceProviders.length; ++count)
{
providerObj = practiceProviders.getItemAt(count, 0).provider as Provider;
if (!providerObj)
continue;
// etc
}
The race condition is a little trickier, given the asyncronous natoure of flex server calls. (I'm assuming that you're loading the data from a remote server).
There's two approaches to solve this - either
defer execution of this method until the data has loaded - you could do this by adding an eventListener to the ResultEvent of the RemoteService
or
Don't worry about it the first time around, but re-execute the method whenever the data changes.
eg:
protected function providerList_creationCompleteHandler(event:FlexEvent):void
{
dataProvider.addEventListener(CollectionEvent.COLLECTION_CHANGE,onCollectionChange,false,0,true);
updateProviders();
// Rest of existing creationComplete code moved to updateProviders();
}
private function updateProviders()
{
// Code from existing creationComplete handler goes here
}
private function onCollectionChange(event:CollectionEvent):void
{
updateProviders();
}
I'm modifying the "Edit.aspx" default page template used by ASP.NET Dynamic Data and adding some additional controls. I know that I can find the type of object being edited by looking at DetailsDataSource.GetTable().EntityType, but how can I see the actual object itself? Also, can I change the properties of the object and tell the data context to submit those changes?
Maybe you have found a solution already, however I'd like to share my expresience on this.
It turned out to be a great pita, but I've managed to obtain the editing row. I had to extract the DetailsDataSource WhereParameters and then create a query in runtime.
The code below works for tables with a single primary key. If you have compound keys, I guess, it will require modifications:
Parameter param = null;
foreach(object item in (DetailsDataSource.WhereParameters[0] as DynamicQueryStringParameter).GetWhereParameters(DetailsDataSource)) {
param = (Parameter)item;
break;
}
IQueryable query = DetailsDataSource.GetTable().GetQuery();
ParameterExpression lambdaArgument = Expression.Parameter(query.ElementType, "");
object paramValue = Convert.ChangeType(param.DefaultValue, param.Type);
Expression compareExpr = Expression.Equal(
Expression.Property(lambdaArgument, param.Name),
Expression.Constant(paramValue)
);
Expression lambda = Expression.Lambda(compareExpr, lambdaArgument);
Expression filteredQuery = Expression.Call(typeof(Queryable), "Where", new Type[] { query.ElementType }, query.Expression, lambda);
var WANTED = query.Provider.CreateQuery(filteredQuery).Cast<object>().FirstOrDefault<object>();
If it's a DD object you may be able to use FieldTemplateUserControl.FindFieldTemplate(controlId). Then if you need to you can cast it as an ITextControl to manipulate data.
Otherwise, try using this extension method to find the child control:
public static T FindControl<T>(this Control startingControl, string id) where T : Control
{
T found = startingControl.FindControl(id) as T;
if (found == null)
{
found = FindChildControl<T>(startingControl, id);
}
return found;
}
I found another solution, the other ones did not work.
In my case, I've copied Edit.aspx in /CustomPages/Devices/
Where Devices is the name of the table for which I want this custom behaviour.
Add this in Edit.aspx -> Page_Init()
DetailsDataSource.Selected += entityDataSource_Selected;
Add this in Edit.aspx :
protected void entityDataSource_Selected(object sender, EntityDataSourceSelectedEventArgs e)
{
Device device = e.Results.Cast<Device>().First();
// you have the object/row being edited !
}
Just change Device to your own table name.