The requested page is not available for the requested platform. You are viewing the content for Default platform.

AppearanceAttribute.Context Property

Specifies the Views representing the activity scope for the conditional appearance rule generated from the current attribute.

Namespace: DevExpress.ExpressApp.ConditionalAppearance

Assembly: DevExpress.Persistent.Base.v19.1.dll

Declaration

public string Context { get; set; }
Public Property Context As String

Property Value

Type Description
String

A string that is semicolon separated names of the Views in which the conditional appearance rule is in effect.

Remarks

The Context property can have the following values.

Context Appearance Rule's Activity Scope Example
A predefined context - "DetailView", "ListView" or "Any". Detail Views, List Views or all Views, respectively. Any
A semicolon-separated list of View identifiers. Specified Views only. MyClass_ListView;MyClass_DetailView
The "Any" predefined context, followed by a semicolon-separated list of View identifiers. All Views except the Views specified via View identifiers. Any;MyClass_ListView;MyClass_LookupListView
The "DetailView" or "ListView" predefined context, followed by a semicolon-separated list of View identifiers. All Detail Views or List Views respectively, in addition to Views specified via View identifiers. DetailView;MyClass_ListView

By default, Context is set to "Any".

Examples

Example 1

According to the rule demonstrated in the example below, the "ProductParameters" layout group caption in the Product Detail View will be displayed in Blue font color when the Category property is set to "Seafood".

using DevExpress.ExpressApp.ConditionalAppearance;
//...
[Appearance("LayoutGroupColoredInDetailView", AppearanceItemType = "LayoutItem",
 TargetItems = "ProductParametersLayoutGroup", Criteria = "Category = 'Seafood'",
 Context = "Product_DetailView", FontColor = "Blue")]
public class Product : BaseObject {
    public Product(Session session) : base(session) { }
    public string Name {
        //...
    }
    public decimal Price {
        //...
    }
    public ProductStatus Status {
        //...
    }
    public Category Category {
        //...
    }
}
[DefaultProperty("Name")]
public class Category : BaseObject {
    public Category(Session session) : base(session) {}
    public string Name {
        //...
    }
}

Example 2

According to the rule demonstrated in the example below, the Product objects whose Price is more than 50 will be displayed in Red background using Maroon font color in List Views.

using DevExpress.ExpressApp.ConditionalAppearance;
//...
[Appearance("RedPriceObject", AppearanceItemType = "ViewItem", TargetItems = "*",
    Criteria = "Price>50", Context = "ListView", BackColor = "Red",
        FontColor = "Maroon", Priority = 2)]
public class Product : BaseObject {
    public Product(Session session) : base(session) { }
    public string Name {
        //...
    }
    public decimal Price {
        //...
    }
    public ProductStatus Status {
        //...
    }
    public Category Category {
        //...
    }
}

Example 3

According to the rule demonstrated in the example below, a Product's Deactivate Action will be hidden when the Status property is set to "Inactive" in all Product Views. Note that the Action ID specified in this rule contains the class name ("Product.Deactivate"), because the Deactivate Action is declared using the ActionAttribute. If an Action is declared in a Controller, specify its ID without the class name, e.g., "Delete" or "Unlink".

using DevExpress.ExpressApp.ConditionalAppearance;
//...
[Appearance("ActionVisibility", AppearanceItemType = "Action",
    TargetItems = "Product.Deactivate",
        Criteria = "Status = 'Inactive'", Context = "Any", Visibility = ViewItemVisibility.Hide)]
public class Product : BaseObject {
    public Product(Session session) : base(session) { }
    public ProductStatus Status {
        //...
    }   
    [Action(PredefinedCategory.RecordEdit, Caption = "Deactivate Product...", AutoCommit = true,
     TargetObjectsCriteria = "Status = 'Active'",
      SelectionDependencyType = MethodActionSelectionDependencyType.RequireSingleObject)]
    public void Deactivate() {
        Status = ProductStatus.Inactive;
    }
}

To see the Appearance attribute in action, refer to the FeatureCenter demo installed with XAF. This demo is located in the %PUBLIC%\Documents\DevExpress Demos 19.1\Components\eXpressApp Framework\FeatureCenter folder by default.

See Also