I'm looking at rehosting the workflow designer. I want to be able to run some code whenever the user adds an activity to the designer canvass. Is there an event that fires when the user adds an activity at design time? Or is there an event on the activity that I can consume? Thanks!
For anyone who might stumble onto this, here's what I figured out...
First off, when creating the workflow designer, you need to subscribe to the ModelChanged event.
_workflowDesigner = new WorkflowDesigner();
_workflowDesigner.Load(new Sequence());
ModelService ms = _workflowDesigner.Context.Services.GetService<ModelService>();
if (ms != null)
ms.ModelChanged += new EventHandler<ModelChangedEventArgs>(ms_ModelChanged);
My event handler looks like this...
void ms_ModelChanged(object sender, ModelChangedEventArgs e)
{
if (e.ItemsAdded != null && e.ItemsAdded.Count<ModelItem>() == 1)
{
ModelItem item = e.ItemsAdded.FirstOrDefault<ModelItem>();
var test = item.GetCurrentValue() as MyActivityType;
if (test != null && test.Id == null)
{
//do whatever initialization logic is needed here
}
}
}
I need to give credit to this source for pointing me in the right direction.
One thing to be careful of - when you move an activity within the model, two events are raised, a remove and an add. At this point, I don't need to worry about whether I'm adding or moving an activity as I can tell whether it has been initialized, but if you need to know whether something has really been added to the model, you might need to track both events.
Related
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
}
In order to verify that all changes made by the user have been saved I want to intercept the exiting/quitting of a JavaFX application.
Is there a common way-to-go to achieve this like overriding an event or is there more to it?
As they have already said, this is done by intercepting WindowEvent.WINDOW_CLOSE_REQUEST. You can then stop the suspension by calling event.consume().
This is an example of how to capture the event and display a confirmation dialog. Depending on the user's choice, you can take serialization actions if you wish.
primaryStage.setOnCloseRequest(event -> {
Alert alert = new Alert(Alert.AlertType.CONFIRMATION);
alert.initOwner(primaryStage);
alert.initModality(Modality.APPLICATION_MODAL);
alert.setHeaderText("Exit");
alert.setContentText("Do you want to exit?");
alert.getDialogPane().getButtonTypes().setAll(ButtonType.OK, ButtonType.NO);
Optional<ButtonType> optional = alert.showAndWait();
if(optional.isPresent() && optional.get() == ButtonType.OK) {
// save data
return;
}
event.consume();
});
In order for the implementation to be complete, you need to implement a logic for clear exit from the application from control. For example, when choosing from the File menu -> Close. When capturing the event, you must run WindowEvent.WINDOW_CLOSE_REQUEST to trick the exit logic.
closeMenuItem.setOnAction(event -> {
Window window = menuBar.getScene().getWindow();
window.fireEvent(new WindowEvent(window, WindowEvent.WINDOW_CLOSE_REQUEST));
});
In the class Application there is the stop method which you can override possibly.
I've some UserControls which are created dynamically, with parameters :
foreach (DataRow dr in drc)
{
question = (from ques in bdd.QUESTION where ques.ID_QUESTION == idQuestion select ques).FirstOrDefault();
List<Object> listParams = new List<Object>();
listParams.Add(question);
AdminQuestion qa = (AdminQuestion)(Controller.LoadControl(Page, "~/UserControls/AdminQuestion.ascx", listParams.ToArray()));
pnl_question_list.Controls.Add(qa);
}
This is a method I found on SoF and it works great.
This method is called when I click on a button, and all my usercontrols are correctly created.
In this usercontrol, I have a button :
<asp:Button ID="btn_validation_modify_question" runat="server" Text="Modifier"
CssClass="clear_left_float_left myBouton myBoutonEnvoyer"
OnClick="btn_validation_modify_question_Click"/>
And my method :
protected void btn_validation_modify_question_Click(object sender, EventArgs e)
{
QUESTION q = (from m in bdd.QUESTION where m.ID_QUESTION == question.ID_QUESTION select m).FirstOrDefault();
q.MESSAGE = txt_modify_question_message.InnerText;
q.ID_THEME = new Guid(ddl_modify_question_theme.SelectedValue);
bdd.ApplyCurrentValues<QUESTION>("QUESTION", q);
bdd.SaveChanges();
}
But when I click on the button, it don't apply the method, and reload the page, like if I didn't have any declared method.
Is there something I don't know? I already used this technique and everything worked...
If you add controls dynamically, you'll normally need to do it on Init or PreInit page events. Otherwise event handlers will never work.
So, dynamically added controls must be programmatically added to the Web page on each and every page visit. The best time to add these controls is during the initialization stage of the page life cycle, which occurs before the load view state stage. That is, we want to have the control hierarchy complete before the load view state stage arrives. For this reason, it is best to create an event handler for the Page class's Init event in your code-behind class, and add your dynamic controls there.
Note You may be able to get away with loading your controls in the
Page_Load
event handler and maintaining the view state properly. It all depends on whether or not you are setting any properties of the dynamically loaded controls programmatically and, if so, when you're doing it relative to the
Controls.Add(dynamicControl)
line. A thorough discussion of this is a bit beyond the scope of this article, but the reason it may work is because the
Controls
property's
Add()
method recursively loads the parent's view state into its children, even though the load view state stage has passed.
Here you have more information.
EDIT
Just to be sure we're talking about the same, here you have how your code should look like
protected void Page_Init(object sender, EventArgs e)
{
...
foreach (DataRow dr in drc)
{
question = (from ques in bdd.QUESTION where ques.ID_QUESTION == idQuestion select ques).FirstOrDefault();
List<Object> listParams = new List<Object>();
listParams.Add(question);
AdminQuestion qa = (AdminQuestion)(Controller.LoadControl(Page, "~/UserControls/AdminQuestion.ascx", listParams.ToArray()));
pnl_question_list.Controls.Add(qa);
}
...
}
PageLoad(){
If(!Page.IsPostBack())
foreach (DataRow dr in drc)
{
question = (from ques in bdd.QUESTION where ques.ID_QUESTION == idQuestion select ques).FirstOrDefault();
List<Object> listParams = new List<Object>();
listParams.Add(question);
AdminQuestion qa = (AdminQuestion)(Controller.LoadControl(Page, "~/UserControls/AdminQuestion.ascx", listParams.ToArray()));
pnl_question_list.Controls.Add(qa);
}
}
Did you try with this solution? And not use Page_Init()?
I am using WF 4 with ASP.NET and as part of the workflow the system may need to redirect to other pages for the user to input additional information under certain circumstances. Once they have entered that information, the system needs to resume the workflow where it left off.
I have this code so far in the initial page that kicks off the process and an activity in the workflow that sets a bookmark.
static InstanceStore instanceStore;
static AutoResetEvent instanceUnloaded = new AutoResetEvent(false);
static Guid id;
protected void Page_Load(object sender, EventArgs e)
{
SetupInstanceStore();
}
protected void btnStartWorkflow_Click(object sender, EventArgs e)
{
app = Session["applicant"];
Dictionary<string, object> workflowInputs = new Dictionary<string, object>();
workflowInputs.Add("Applicant", app.Applicant);
WorkflowApplication workflowApplication = new WorkflowApplication(new IdentityCheckActivites.IdentityCheckWorkflow(), workflowInputs);
workflowApplication.InstanceStore = instanceStore;
//returning IdleAction.Unload instructs the WorkflowApplication to persist application state and remove it from memory
workflowApplication.PersistableIdle = (a) =>
{
return PersistableIdleAction.Persist;
};
workflowApplication.Unloaded = (a) =>
{
instanceUnloaded.Set();
};
workflowApplication.Completed = (a) =>
{
instanceUnloaded.Set();
};
workflowApplication.Persist();
id = workflowApplication.Id;
workflowApplication.Run();
Session["id"] = id;
workflowApplication.Idle = (a) =>
{
instanceUnloaded.Set();
};
instanceUnloaded.WaitOne();
var bookmarks = workflowApplication.GetBookmarks();
if (bookmarks != null && bookmarks[0].OwnerDisplayName == "CC")
{
workflowApplication.Unload();
Context.Response.Redirect("SecondPage.aspx");
}
Context.Response.Redirect("FinalPage.aspx");
}
private static void SetupInstanceStore()
{
instanceStore = new SqlWorkflowInstanceStore(#"Data Source=xxx;Initial Catalog=SampleInstanceStore;User Id=xxx;Password=xxx;Asynchronous Processing=True");
InstanceHandle handle = instanceStore.CreateInstanceHandle();
InstanceView view = instanceStore.Execute(handle, new CreateWorkflowOwnerCommand(), TimeSpan.FromSeconds(30));
handle.Free();
instanceStore.DefaultInstanceOwner = view.InstanceOwner;
}
This seems to work very well in that it persists the workflow to the database and if the bookmark is set I want to redirect to a second page for the user to enter more data.
This is the part of the code that I am having problems with: -
var bookmarks = workflowApplication.GetBookmarks();
if (bookmarks != null && bookmarks[0].OwnerDisplayName == "CC")
{
workflowApplication.Unload();
Context.Response.Redirect("SecondPage.aspx");
}
Context.Response.Redirect("FinalPage.aspx");
If there's a bookmark set, I redirect to an intermediary page, if not and no user intervention was necessary, the page will just redirect to the final page.
This works if the bookmark is set, but if not the workflowApplication.GetBookmarks() statement throws an exception telling me that the workflow has completed.
I can't seem to find a way to detect at this stage which state the workflow is in so that I can redirect to the relevant page.
Maybe I have the wrong idea in general, as much as I search though, I cannot seem to find a lot of guidance on this subject.
Any ideas?
Thanks,
Jim.
I don't think there is a way to directly determine if the workflow is completed from WorkflowApplication (except for catching and inspecting the exception that is thrown).
But you could set a flag in side your Completed delegate which is executed only if the there is no bookmark set and the workflow is completed. You could then check this flag before calling GetBookmarks().
Not sure if I understand exactly, but it seems that your page controller is looking at the state of the workflow to understand what page to redirect to? The problem is that the state may be non-existent if the WF instance has ended?
If the above is correct then perhaps the approach is wrong. A more appropriate approach might be to have a WCF WF service on AppFabric (correlated by session id) handle the website request directly. (If a user in a particular session visits the site, then the WF determines what page to render, and if the user hits a certain button, then send a WCF WF message using net pipe binding)
instead of
workflow.idle
you need
wfApp.PersistableIdle
and don't forget
instanceUnloaded.Set();
myGridView.DataSource = LinqDataSource works but only for select. I have edit and delete columns and when I try to use them I get errors about events not getting caught. Specifically I've seen OnRowDeleting, but I'm sure there are others that need to be wired up.
myGridView.OnRowDeleting = ??
I can't seem to find anything on the LinqDataSource that looks like what I need :(
edit: here is some some sample code illustrating what I'm doing.
protected virtual void OnRowDeleted(Object sender, GridViewDeletedEventArgs e)
{
// it means the last row was deleted
if (fieldGridView.Rows.Count == 1)
{
fieldGridView.DataSourceID = null;
fieldGridView.DataSource = new[] { new FormField { Required = false } };
fieldGridView.AutoGenerateDeleteButton = false;
fieldGridView.AutoGenerateEditButton = false;
}
}
protected void InsertButton_Click(object sender, CommandEventArgs e)
{
// pull data out of footer row and insert it into the DB
if (fieldGridView.DataSource == null || fieldGridView.DataSource.GetType() != LinqDataSource1.GetType())
{
fieldGridView.DataSource = LinqDataSource1;
fieldGridView.AutoGenerateDeleteButton = true;
fieldGridView.AutoGenerateEditButton = true;
}
}
Also note that I've statically set the OnRowDeleting event in the markup and the error went away. However, the Linq data source is not getting set back properly. The code is updating it, it's just sticking for whatever reason, so what's happening is that when I re-enable the delete column the data source ends up still being the temp data source I assigned to it (which is just a list), so when I hit delete it was blowing up. Since I've now statically defined the callback, it gets called, but no delete happens because the data source isn't being switched back to the linq data source properly.
so in essence, my issue is that when I dynamically set the data source to the list on the last delete, the change is sticking, but when I dynamically set the data source to the linq data source on the first insert, the change is not sticking. The strangest part of it is that other changes I'm making do stick, just not the data source. I'm enabling the autogenerated edit and delete columns and that change is being reflected immediately.
On your linq datasource, did you remember to explicitly set the enable flags for delete and insert?
<asp:LinqDataSource ID="MyLinqDataSource" EnableDelete="true" EnableUpdate="true" EnableInsert="true" runat="server" ....
Ultimately I was not able to fix this specific issue, but I did find a workaround for my larger issue.
In essence what I've done is to create two gridviews with different data sources, created a custom delete button for each row, and then swap the grids out accordingly. Not exactly a great solution, but it suffices for what I'm doing.
As for why my original solution of swapping the datasources doesn't work, I don't know. Most of the projects I've been on have used non-MS tools for tabulated data so I'm not even sure where to look. However, if anyone has any good ideas as to why I've encountered this behavior, I'm all ears.