How to search for XAF objects using a complex criterion

This example creates a pop-up window that allows users to perform a custom object search.

Implementation Details

1. Create a non-persistent class with properties used to search persistent objects.
   File to review: MySearchClass.cs

   [DomainComponent]
   public class MySearchClass : NonPersistentBaseObject {
       [XafDisplayName("FirstName contains:")]
       public string FirstName { get; set; }
       [XafDisplayName("Age is equal to:")]
       public int Age { get; set; }
       // ...
   }

2. Add a collection of persistent objects that contains the search results.
   File to review: MySearchClass.cs

   [DomainComponent]
   public class MySearchClass : NonPersistentBaseObject {
       // ...
       private IList<Contact> _contacts = new List<Contact>();
       [XafDisplayName("Results:")]
       public IList<Contact> Contacts {
           get {
               return _contacts;
           }
       }
   }

3. Add the MySearch action that populates the collection. File to review: MySearchController.cs

   public class MySearchController : ObjectViewController<DetailView, MySearchClass> {
       public MySearchController() {
           var myAction1 = new SimpleAction(this, "MySearch", "MySearchCategory");
           myAction1.Execute += MyAction1_Execute;
       }
       // ...
   }

4. When a user clicks the MySearch action, create a criterion based on the properties described in the first step and get persistent objects that fit this criterion.
   File to review: MySearchController.cs

   public class MySearchController : ObjectViewController<DetailView, MySearchClass> {
       // ...
       private void MyAction1_Execute(object sender, SimpleActionExecuteEventArgs e) {
           var mySearchObject = (MySearchClass)View.CurrentObject;
           var persistentOS = Application.CreateObjectSpace(typeof(Contact));
           var criterion = CriteriaOperator.FromLambda<Contact>(x => x.FirstName.Contains(mySearchObject.FirstName) || x.Age == mySearchObject.Age);
           var results = persistentOS.GetObjects<Contact>(criterion);
           mySearchObject.SetContacts(results);
       }
   }

5. Create the MyShowSearchAction to display the MySearchClass detail view from the Contact list view in a pop-up window. File to review: MyShowSearchController.cs

   public class MyShowSearchController : ObjectViewController<ListView, Contact> {
       public MyShowSearchController() {
           var mypopAction1 = new PopupWindowShowAction(this, "MyShowSearchAction", PredefinedCategory.Edit);
           mypopAction1.TargetViewNesting = Nesting.Root;
           mypopAction1.CustomizePopupWindowParams += MyAction1_CustomizePopupWindowParams;
       }
       private void MyAction1_CustomizePopupWindowParams(object sender, CustomizePopupWindowParamsEventArgs e) {
           var nonPersistentOS = (NonPersistentObjectSpace)Application.CreateObjectSpace(typeof(MySearchClass));
           var persistentOS = Application.CreateObjectSpace(typeof(Contact));
           nonPersistentOS.AdditionalObjectSpaces.Add(persistentOS);
           var obj = nonPersistentOS.CreateObject<MySearchClass>();
           nonPersistentOS.CommitChanges();
           var view = Application.CreateDetailView(nonPersistentOS, obj);
           e.View = view;
       }
   }

Files to Review

• MySearchClass.cs
• Model.DesignedDiffs.xafml
• MySearchController.cs
• MyShowSearchController.cs

Documentation

• Non-Persistent classes
• How to: Show Persistent Objects in a Non-Persistent Object's View
• How to: Include an Action to a Detail View Layout
• Create, Read, Update and Delete Data
• Ways to Show a View

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