DevForce Community Forum : Updating Custom Properties http://www.ideablade.com/forum/ This is an XML content feed of; DevForce Community Forum : DevForce Classic : Updating Custom Properties Fri, 12 Jun 2026 10:01:00 -700 Mon, 18 Jun 2007 14:48:18 -700 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 9.69 360 www.ideablade.com/forum/RSS_post_feed.asp?TID=88 DevForce Community Forum http://www.ideablade.com/forum/forum_images/IdeaBlade_logo_tm.png http://www.ideablade.com/forum/ Updating Custom Properties : The TechTip on "Refreshing... http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=181#181 Author: davidklitzke
Subject: 88
Posted: 18-Jun-2007 at 2:48pm

The TechTip on "Refreshing Dependent Parents" is excellent, but I thought I would try my hand on one of the tutorials.  I started with the Fundamental tutorial on "Populating a Winform".  First, I created a custom property for TotalCost:
 

public decimal TotalCost {

      get {

        decimal total = 0;

        foreach (OrderDetail detail in this.OrderDetails) {

          total += detail.UnitPrice * detail.Quantity;

        }

        return total;

      }

    }

Then, I added an OnColumnChanging Event Handler for OrderDetail:

    protected override void OnColumnChanged(DataColumnChangeEventArgs pArgs) {

      base.OnColumnChanged(pArgs);

      this.Order.ForcePropertyChanged(null);

    }

 
I thought that this would be all I needed, but I didn't see an immediate change in TotalCost.  As a last resort, I tried adding a ForcePropertyChanged for the Employee as well:
 

protected override void OnColumnChanged(DataColumnChangeEventArgs pArgs) {

    base.OnColumnChanged(pArgs);

    this.Order.ForcePropertyChanged(null);

    PrimaryKey pKey = new PrimaryKey(typeof(Employee), this.Order.EmployeeId);

    Employee aEmployee = (Employee)this.PersistenceManager.GetEntity(pKey);

    aEmployee.ForcePropertyChanged(null);

 }
 
I am not sure why the ForcePropertChanged on Employee is necessary, but I suspect it is because this tutorial uses chained bindings.
 
]]> Mon, 18 Jun 2007 14:48:18 -700 http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=181#181 Updating Custom Properties : Jeff, Perfect! I added a few... http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=180#180 Author: Linguinut
Subject: 88
Posted: 18-Jun-2007 at 2:41pm

Jeff,
 
Perfect!  I added a few appropriate overrides and the form reacts beautifully.  Thanks a bunch!  The tech tip was exactly what I needed.
 
Take care,
Bill
]]> Mon, 18 Jun 2007 14:41:41 -700 http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=180#180 Updating Custom Properties : Check out the TechTip on Refreshing... http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=179#179 Author: jeffdoolittle
Subject: 88
Posted: 18-Jun-2007 at 2:07pm

Check out the TechTip on Refreshing Dependent Parents:

http://www.ideablade.com/techtip_refreshing_dependent_parents.htm
]]> Mon, 18 Jun 2007 14:07:18 -700 http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=179#179 Updating Custom Properties : I have a set of tables in a master-detail... http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=178#178 Author: Linguinut
Subject: 88
Posted: 16-Jun-2007 at 11:16am

I have a set of tables in a master-detail relationship...let's call them orders and details for simplicity.  In the orders entity I have added a custom property called TotalDetails.  This iterates through the details related to the order and totals up the extended price (sum of price times quantity).  Simple enough.  Now, the details are displayed in a grid on the order form.  If I change a price or quantity in the grid, I would expect the TotalDetails property to change.  It doesn't.  The property updates if I navigate away from the order and return to it.  How do I get the custom property to update dynamically without changing entities?

Thanks!

Bill

]]> Sat, 16 Jun 2007 11:16:36 -700 http://www.ideablade.com/forum/forum_posts.asp?TID=88&PID=178#178