AppearanceAttribute(String) Constructor

Creates a new instance of the AppearanceAttribute class.

Namespace: DevExpress.ExpressApp.ConditionalAppearance

Assembly: DevExpress.Persistent.Base.v23.2.dll

NuGet Package: DevExpress.Persistent.Base

Declaration

C#

public AppearanceAttribute(
    string id
)

VB.NET

Public Sub New(
    id As String
)

Parameters

Name	Type	Description
id	String	A string that is the unique identifier for the appearance rule created using the current attribute instance.

Remarks

This constructor sets the following attribute properties:

• AppearanceAttribute.Id is set to the value passed as the id parameter;
• AppearanceAttribute.Context is set to Any (a default value);
• AppearanceAttribute.AppearanceItemType is set to ViewItem (a default value).

The remaining properties can be specified using the constructor’s named parameters.

To learn how to define a rule using the Appearance attribute, refer to the Declare Conditional Appearance Rules in Code topic.

Example

According to the rule demonstrated in the example below, the Category property in List Views will be displayed in Blue font color when its value is “Seafood”.

C# (EF Core)

using DevExpress.ExpressApp.ConditionalAppearance;
//...
[Appearance("CategoryColoredInListView", AppearanceItemType = "ViewItem", TargetItems = "Category",
 Criteria = "Category = 'Seafood'", Context = "ListView", FontColor = "Blue", Priority = 1)]
public class Product : BaseObject {
    public virtual Category Category { get; set; }
}

[DefaultProperty(nameof(Name))]
public class Category : BaseObject {
    public virtual string Name { get; set; }
}

// Make sure that you use options.UseChangeTrackingProxies() in your DbContext settings.

C# (XPO)

using DevExpress.ExpressApp.ConditionalAppearance;
//...
[Appearance("CategoryColoredInListView", AppearanceItemType = "ViewItem", TargetItems = "Category",
 Criteria = "Category = 'Seafood'", Context = "ListView", FontColor = "Blue", Priority = 1)]
public class Product : BaseObject {
    public Product(Session session) : base(session) { }
    public Category Category {
        //...
    }
}
[DefaultProperty(nameof(Name))]
public class Category : BaseObject {
    public Category(Session session) : base(session) {}
    public string Name {
        //...
    }
}

VB.NET (XPO)

Imports DevExpress.ExpressApp.ConditionalAppearance
'...
<Appearance("CategoryColoredInListView", AppearanceItemType := "ViewItem", TargetItems := "Category",
 Criteria := "Category = 'Seafood'", Context := "ListView", FontColor := "Blue", Priority := 1)> _
Public Class Product
        Inherits BaseObject
    Public Sub New(ByVal session As Session)
        MyBase.New(session)
    End Sub
    Public ReadOnly Property Category() As Category
        '...
    End Property
End Class
<DefaultProperty(NameOf(Name))> _
Public Class Category
        Inherits BaseObject
    Public Sub New(ByVal session As Session)
        MyBase.New(session)
    End Sub
    Public ReadOnly Property Name() As String
        '...
    End Property
End Class

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the AppearanceAttribute(String) constructor.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

XAF_Non-Persistent-Objects-Filtering-Demo/CS/NonPersistentObjectsDemo.Module/BusinessObjects/Article.cs#L15

[DefaultProperty(nameof(Article.Title))]
[DevExpress.ExpressApp.ConditionalAppearance.Appearance("", Enabled = false, TargetItems = "*")]
[DevExpress.ExpressApp.DC.DomainComponent]

XAF_treelisteditor-how-to-enable-in-place-editing-in-the-winforms-tree-list-view-e443/CS/WinSolution.Module/Classes2.cs#L14

[NavigationItem]
[Appearance("Can Edit Items", TargetItems = "Items", Criteria = "!CanEdit", Enabled = false)]
public class OwnerClass : BaseObject {

xaf-web-forms-use-oauth2-authentication-providers/CS/MySolution.Module/BusinessObjects/ApplicationUserLoginInfo.cs#L16

[Indexed("ProviderUserKey", Unique = true)]
[Appearance("PasswordProvider", Enabled = false, Criteria = "!(IsNewObject(this)) and LoginProviderName == '" + SecurityDefaults.PasswordAuthentication + "'", Context = "DetailView")]
public string LoginProviderName {

xaf-how-to-change-connection-to-the-database-at-runtime/CS/XPO/NET_Framework/RuntimeDbChooser.Module/BusinessObjects/ApplicationUserLoginInfo.cs#L16

[Indexed("ProviderUserKey", Unique = true)]
[Appearance("PasswordProvider", Enabled = false, Criteria = "!(IsNewObject(this)) and LoginProviderName == '" + SecurityDefaults.DefaultClaimsIssuer + "'", Context = "DetailView")]
public string LoginProviderName {

xaf-custom-logon-parameters/CS/XPO/WebForms/CustomLogonXPOWeb/CustomLogonXPOWeb.Module/BusinessObjects/ApplicationUserLoginInfo.cs#L16

[Indexed("ProviderUserKey", Unique = true)]
[Appearance("PasswordProvider", Enabled = false, Criteria = "!(IsNewObject(this)) and LoginProviderName == '" + SecurityDefaults.PasswordAuthentication + "'", Context = "DetailView")]
public string LoginProviderName {

VB.NET

XAF_Non-Persistent-Objects-Filtering-Demo/VB/NonPersistentObjectsDemo.Module/BusinessObjects/Article.vb#L15

<DefaultProperty(NameOf(Article.Title))>
<DevExpress.ExpressApp.ConditionalAppearance.Appearance("", Enabled := False, TargetItems := "*")>
<DevExpress.ExpressApp.DC.DomainComponent>

XAF_treelisteditor-how-to-enable-in-place-editing-in-the-winforms-tree-list-view-e443/VB/WinSolution.Module/Classes2.vb#L13

<NavigationItem, Appearance("Can Edit Items", TargetItems := "Items", Criteria := "!CanEdit", Enabled := False)> _
Public Class OwnerClass

xaf-web-forms-use-oauth2-authentication-providers/VB/MySolution.Module/BusinessObjects/ApplicationUserLoginInfo.vb#L19

<Indexed("ProviderUserKey", Unique:=True), Appearance("PasswordProvider", Enabled:=False, Criteria:="!(IsNewObject(this)) and LoginProviderName == '" & SecurityDefaults.PasswordAuthentication & "'", Context:="DetailView")>
Public Property LoginProviderName() As String Implements ISecurityUserLoginInfo.LoginProviderName

XAF-How-to-Implement-CRUD-Operations-for-Non-Persistent-Objects-Stored-Remotely/VB/NonPersistentObjectsDemo.Module/BusinessObjects/AuxiliaryObjects.vb#L84

'[Browsable(false)]
<DevExpress.ExpressApp.ConditionalAppearance.Appearance("", Enabled := False, Criteria := "Not IsNewObject(This)")>
<RuleRequiredField>

How-To-Set-Permissions-States-Automatically/VB/SecuritySetState.Module/BusinessObjects/Contact.vb#L23

<DebuggerDisplay("FirstName: {FirstName}")>
<Appearance("RedPriceObject", AppearanceItemType := "ViewItem", TargetItems := "TestBool,LastName", Enabled := False)>
Public Class Contact