View.AllowEdit Property

Provides access to a collection of reason/value pairs used to make a View read-only/editable.

Namespace: DevExpress.ExpressApp

Assembly: DevExpress.ExpressApp.v23.2.dll

NuGet Package: DevExpress.ExpressApp

Declaration

C#

public BoolList AllowEdit { get; }

VB.NET

Public ReadOnly Property AllowEdit As BoolList

Property Value

Type	Description
BoolList	A BoolList object that represents a collection of key/value elements.

Remarks

The example below demonstrates how to make all Detail Views in an application read-only.

C#

using DevExpress.ExpressApp;
// ...
public class MakeDetailViewsReadOnlyController : ViewController<DetailView> {
    protected override void OnActivated() {
        base.OnActivated();
        View.AllowEdit["ReadOnly"] = false;
    }
}

VB.NET

Imports DevExpress.ExpressApp

Public Class MakeDetailViewsReadOnlyController
    Inherits ViewController(Of DetailView)
    Protected Overrides Sub OnActivated()
        MyBase.OnActivated()
        View.AllowEdit("ReadOnly") = False
    End Sub
End Class

There can be various reasons to make a View read-only or editable. So, a View has the AllowEdit collection, whose elements represent a pair of string and Boolean values. The string value specifies a reason and the Boolean value specifies whether to make the View editable for this reason. A View is considered read-only if at least one of the AllowEdit collection elements contains a false value.

The read-only state of a Detail View and List View is characterized by the following:

• Detail View

  All Property Editors are created in read-only mode.

• List View

  Inplace editing is not allowed.

To determine whether a View is currently read-only, use the AllowEdit property in a conditional expression. Alternatively, use the BoolList.ResultValue property of the object returned by AllowEdit.

C#

View myView;
//...
BoolList editableList = myView.AllowEdit;
if (editableList) {
    //...
}

VB.NET

Dim myView As View
'...
Dim editableList As BoolList = myView.AllowEdit
If editableList.ResultValue Then
    '...
End If

To make an editable View read-only, use the BoolList.SetItemValue method of the BoolList object returned by this property. Pass the reason for making the View read-only as the first parameter, and false or a Boolean expression as the second parameter. Alternatively, you can use the [key] operator of the BoolList object returned by the AllowEdit property, to get or set the specified key’s value.

C#

View myView;
//...
BoolList editableList = myView.AllowEdit;
editableList["myKey"] = false;

VB.NET

Dim myView As View
'...
Dim editableList As BoolList = myView.AllowEdit
editableList("myKey") = False

To make a read-only View editable, use the BoolList.RemoveItem method of the BoolList object returned by this property. Pass the key (reason) of the item with the false value. Call this method as many times as there are items with the false value. Alternatively, you can call the BoolList.SetItemValue method by passing the key, which has false as a value, and true as a new value for it.

C#

View myView;
//...
BoolList editableList = myView.AllowEdit;
editableList["disablingKey"] = true;

VB.NET

Dim myView As View
'...
Dim editableList As BoolList = myView.AllowEdit
editableList("disablingKey") = True

C#

public class MyController : ViewController {
   private void UpdateViewStateEventHandler(object sender, EventArgs e) {
      View.AllowEdit.SetItemValue("CurrentUser", SecuritySystem.CurrentUser.FirstName == "Sam");
   }
   protected override void OnActivated() {
      base.OnActivated();
      View.CurrentObjectChanged += UpdateViewStateEventHandler;
   }
}

VB.NET

Public Class MyController
      Inherits ViewController
   Private Sub UpdateViewStateEventHandler(ByVal sender As Object, ByVal e As EventArgs)
      View.AllowEdit.SetItemValue("CurrentUser", SecuritySystem.CurrentUser.FirstName = "Sam")
   End Sub
   Protected Overrides Sub OnActivated()
      MyBase.OnActivated()
      AddHandler View.CurrentObjectChanged, AddressOf UpdateViewStateEventHandler
   End Sub
End Class

When a View’s read-only state is changed, the View.AllowEditChanged event is raised.