DockPanelSettings.LoadContentViaCallback Property
Gets or sets a value specifying the content loading mode for the DockPanel.
Namespace: DevExpress.Web.Mvc
Assembly: DevExpress.Web.Mvc5.v24.1.dll
NuGet Package: DevExpress.Web.Mvc5
Declaration
Property Value
| Type | Description |
|---|---|
| LoadPanelContentViaCallback | One of the LoadPanelContentViaCallback enumeration values. |
Available values:
| Name | Description |
|---|---|
| None | Specifies that the content is always (initially) rendered inside panels. |
| OnFirstShow | Specifies that loading panel contents occurs when a panel is invoked for the first time. |
| OnPageLoad | Specifies that loading panel contents occurs immediately after the entire page has been loaded. |
| OnDock | Specifies that loading panel contents occurs after a panel is docked or it changes a position within a zone via end-user interaction. If the panel is initially docked, the panel content is loaded on the Page_Load. |
| OnFloating | Specifies that loading panel contents occurs after a panel leaves a zone (undocks) or after it is moved (in the floating state) via an end-user interaction. |
| OnDockStateChange | Specifies that loading panel contents occurs after a panel changes its state, changes its position within a zone, or is moved (in the floating state) via an end-user interaction. |
Remarks
Use the LoadContentViaCallback property to control when a panel’s contents should be loaded.
Note
To enable loading content via callback, it is necessary to define route values to the controller and the action that will handle DockPanel’s callbacks. Use the PopupControlSettingsBase.CallbackRouteValues (via DockPanelSettings.CallbackRouteValues) property to define the callback route values.
Using the postponed load of panel contents (by setting the LoadContentViaCallback property to LoadPanelContentViaCallback.OnPageLoad or LoadPanelContentViaCallback.OnFloating), you can enhance the response time of your web page on its initial load.
You can load panel contents every time the panel is docked (LoadPanelContentViaCallback.OnDock), undocked (LoadPanelContentViaCallback.OnFloating), or on every dock state change (LoadPanelContentViaCallback.OnDockStateChange).
Note that you can also update the content of panels programmatically, on demand (by using the client ASPxClientPopupControlBase.PerformCallback method). On-demand panel loading is realized by sending a callback to the server for the panel’s content. During a callback, a specific loading panel can be displayed within the panel.