CheckBoxProperties.AllowGrayed Property

Gets or sets a value specifying whether the grayed state is available for a check box.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v24.2.dll

Declaration

C#

[DefaultValue(false)]
public bool AllowGrayed { get; set; }

VB.NET

<DefaultValue(False)>
Public Property AllowGrayed As Boolean

Property Value

Type	Default	Description
Boolean	false	true if the grayed state is available; otherwise, false.

Remarks

By default, a check box can be set to either the checked or unchecked check state. To enable the third grayed state, set the AllowGrayed property to true. To prohibit end-users from setting the grayed state via a mouse click, set the CheckBoxProperties.AllowGrayedByClick property to false. In this case, you can set a check box to the grayed state programmatically via the ASPxCheckBox.CheckState property on the server side and calling the ASPxClientCheckBox.SetCheckState method on the client side.

Note

• If the AllowGrayed is set to false, you cannot set the ASPxCheckBox.CheckState property to Indeterminate (the grayed state), it is automatically changed to Unchecked.
• The AllowGrayed property is not in effect for the radio button.

Example

This example illustrates how to customize ASPxCheckBox and GridViewDataCheckColumn if database data is kept in a format different from Boolean.

Default.aspx

<dx:ASPxGridView ID="grid" runat="server" AutoGenerateColumns="False" DataSourceID="xds"
    KeyFieldName="Oid">
    <Columns>
        <dx:GridViewCommandColumn VisibleIndex="0" ShowEditButton="True"/>
        <dx:GridViewDataTextColumn FieldName="Oid" ReadOnly="True" VisibleIndex="1" SortOrder="Ascending">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="Title" VisibleIndex="2" Visible="false">
            <EditFormSettings Visible="True" />
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataCheckColumn FieldName="Allow" VisibleIndex="3">
            <PropertiesCheckEdit AllowGrayed="true" ValueType="System.String" ValueChecked="allowed"
                ValueUnchecked="not allowed" ValueGrayed="no information" />
        </dx:GridViewDataCheckColumn>
        <dx:GridViewDataCheckColumn FieldName="Active" VisibleIndex="4">
            <DataItemTemplate>
                <dx:ASPxCheckBox ID="chk" runat="server" AllowGrayed="true" ValueType="System.Int32"
                    ValueChecked="1" ValueUnchecked="-1" ValueGrayed="0" Value='<%# Eval("Active") %> '
                    OnInit="chk_Init">
                </dx:ASPxCheckBox>
            </DataItemTemplate>
            <EditFormSettings Visible="False" />
        </dx:GridViewDataCheckColumn>
    </Columns>
</dx:ASPxGridView>
<dx:XpoDataSource ID="xds" runat="server" TypeName="MyObject">
</dx:XpoDataSource>

XpoHelper.cs

static void CreateDefaultObjects() {
    using (UnitOfWork uow = GetNewUnitOfWork()) {
        MyObject obj = new MyObject(uow);
        obj.Title = "Test1";
        obj.Active = 1;
        obj.Allow = "allowed";

        obj = new MyObject(uow);
        obj.Title = "Test2";
        obj.Active = 0 ;
        obj.Allow = "allowed";

        obj = new MyObject(uow);
        obj.Title = "Test3";
        obj.Active = -1;
        obj.Allow = "no information";

        obj = new MyObject(uow);
        obj.Title = "Test4";
        obj.Active = 0;
        obj.Allow = "not allowed";

        uow.CommitChanges();
    }
}