asp.net callback devexpress aspxgridview

ASPxGridView CustomCallback

this is the aspx code for my ASPxGridView

<dx:ASPxGridView ID="dgJournalList" runat="server" ClientInstanceName="dgJournalList" 
    OnCustomCallback="dgJournalList_CustomCallback"
    OnCustomJSProperties="dgJournalList_CustomJSProperties" 
    KeyFieldName="LineNo" AutoGenerateColumns="False">
    <SettingsPager Visible="False">
    </SettingsPager>
    <SettingsDataSecurity AllowDelete="False" AllowEdit="False" AllowInsert="False" />
    <Columns>
        <dx:GridViewDataTextColumn FieldName="ItemNo" VisibleIndex ="1" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="PostingDateStr" VisibleIndex ="2" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="EntryTypeStr" VisibleIndex ="3" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="DocumentNo" VisibleIndex ="4" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="LocationCode" VisibleIndex ="5" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="Qty" VisibleIndex ="6" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="UOM" VisibleIndex ="7" 
            ReadOnly="true" Visible="true">
        </dx:GridViewDataTextColumn>
    </Columns>
    <ClientSideEvents EndCallback ="onEndCallback(s, e)" />
</dx:ASPxGridView>

the function from javascript

onButtonClick = function (args)
{
    switch (args)
    {
        case 'refresh':
            dgJournalList.PerformCallback('Refresh');
            break;
    }
}

and the method for callback

protected void dgJournalList_CustomCallback(object sender, ASPxGridViewCustomCallbackEventArgs e)
{
    string[] param = e.Parameters.Split(separator, StringSplitOptions.None);
    BOResponse objResponse = new BOResponse();

    switch (param[0])
    {
        case "Refresh":
            objResponse = GetListJournal(null);
            if (objResponse.MsgCode != 0)
            {
                dgJournalList.JSProperties["cpErrMsg"] = objResponse.MsgDesc;
            }
            dgJournalList.DataSource = JournalList;
            dgJournalList.DataBind();
            dgJournalList.FocusedRowIndex = 0;
            break;
        }            
    }

When performing the refresh action, my application doesn't call back, doing the postback instead, as, when debugging, the breakpoint at the callback method isn't reached; it's hitting a breakpoint at Page_Load method.

Where is my code failing?

Solution

what you see is a normal behavior. Postback means complete page reload. Do you observe it your case? Based on the code you've posted you should't. You should see only the grid area reload.

Page_Init and Page_Load events will be fired after you've called dgJournalList.PerformCallback('Refresh'); in Javascript. Then the control will be handed to your dgJournalList_CustomCallback method.

If you don't want the Page_Init and Page_Load logic be executed during grid's custom callback, then add the following checks into those event handlers:

if (!IsPostBack && !IsCallback)
{
    // your code which is run ONLY at initial page load should be put here
}

If you need to run Page_Init and Page_Load code during some button clicks which do cause postback, then remove the IsPostBack part from the above condition.