I'm using DotNetNuke 4.9.2 and am running into an odd issue.
I have a MultiView in the module that I'm developing, and in one of the views have a GridView that is bound to an ObjectDataSource.
In a separate view, i have several buttons that will switch the SelectMethod of the ObjectDataSource in the 2nd view and then set that view active. That all works fine, until the grid is sorted on the 2nd view - which causes a postback and the ODS somehow picks up its original SelectMethod. The SelectParameters that are assigned at the same time in the code-behind stick though.
Seems to me that the ObjectDataSource should be remembering the SelectMethod in viewstate, shouldn't it?
<asp:ObjectDataSource runat="server" ID="MyObjectDataSource" SelectMethod="MyFirstSelectMethod" TypeName="Whatever"></asp:ObjectDataSource>
protected void Button1_Click(object sender, EventArgs e)
{
MyObjectDataSource.SelectMethod = "MyNewMethod";
// more code here to change the parameters as well...
MyMultiView.SetActiveView(MyView2);
}
When I run that button click, the grid displays as expected. When I click on one of the column headers for the GridView and break in the page load to inspect the SelectMethod, it has reverted to the one declared in the markup.
Any suggestions as to what my problem could be here?
I'm guessing you've made sure that you're not resetting .SelectMethod when the page reloads?
I ended up working around the issue by just using a page property to hold the selectmethod, and then resetting it on each postback...
protected string MySelectMethod
{
get
{
return (string)ViewState["MySelectMethod"] ?? MySearchResultsDataSource.SelectMethod;
}
set
{
ViewState["MySelectMethod"] = value;
MySearchResultsDataSource.SelectMethod = value;
}
}
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
MySearchResultsDataSource.SelectMethod = MySelectMethod;
}
}
protected void MyButton_Click(object sender, EventArgs e)
{
MySelectMethod = "MyNewMethod";
}
Still not sure why that SelectMethod prop doesn't stick on a postback in nuke. I'm sure this has worked fine for me in straight asp.net projects in the past...
Related
I have 5 dropdownlist in asp.net.User selects 5 dropdownlist after that click to button.Button sends page to another page.If i go previous page dropdownlist selectedvalues and datas lose(it displays default values without selected values)
I tried below
Response.Redirect("PreviousPage.aspx");
datas losing is there any solution ?
Instead of using Response.Redirect(), you can change the PostBackUrl of the button to the target page, or use Server.Transfer(). Once there you should be able to access the properties you need from the Page.PreviousPage object.
Example using Server.Transfer:
Page1.aspx.cs:
protected void SubmitButton_Click(object sender, EventArgs e)
{
Server.Transfer("Page2.aspx");
}
Page2.aspx.cs:
protected void Page_Load(object sender, EventArgs e)
{
var addressDropdownSelectedValue = ((Page1)Page).PreviousPage.AddressDropdown.SelectedItem.Value; //or SelectedValue
}
With the ScriptManager in the AJAX control toolkit (you get this in 4.0+, I think maybe even in 3.5), you can add history points. You add a history point and use that value to rebuild the page state.
http://msdn.microsoft.com/en-us/library/cc488548%28v=vs.140%29.aspx
You can also strongly type the previous page if you want to grab values from it. You do this with <%# PreviousPage %> directive. Then in code you could use Page.PreviousPage.FindControl
I made researching about this subject I could not find proper answer.
In my default.aspx page, I have a treeview. Codes are in default.aspx like below:
protected void Page_Load(object sender, EventArgs e)
{
}
protected void TreeView1_SelectedNodeChanged(object sender, EventArgs e)
{
Control ucont;
if (TreeView1.SelectedNode.Value == "Yeni Dönem")
{
ucont = LoadControl("usercontrols/yenidonem.ascx");
PlaceHolder1.Controls.Add(ucont);
}
else
{
ucont = LoadControl("usercontrols/tabloktar.ascx");
PlaceHolder1.Controls.Add(ucont);
}
}
I load user controls dnynmicaly. User controls are have button control. I can not fire user control's button click when I load it dynamcally. How can I solve this ?
Thanks.
First of all, I would not recommend adding control dynamically later than in Page_Load event. Other things to remember is that You should add it on each page load and assign unique ID value the control that does not change between postbacks.
In this case, the easiest way would be to always add both controls to the page and show appropriate one using Visibility property.
If that's not suitable for You, try to move the code from TreeView1_SelectedNodeChanged to the Page_Load event and load appropriate control on each postback until it should be changed to another one.
I haven't tested this, so if You have any issues when using thise answer, let me know in the comments and I'll try to help.
I've written a custom widget to allow a user to select a location from a database of locations. This is my first ASP.net custom control. It seemed like everything was working fine, but now there's a problem.
My control implements the RaisePostBackEvent function as follows:
public void RaisePostBackEvent(string eventArgument)
{
SelectedLocationId = eventArgument.Split('|')[0];
SelectedLocationDescription = eventArgument.Split('|')[1];
}
I wrote a test page and included the following in my ASP code:
<%= locationSelector.SelectedLocationId %>
That worked fine.
However, in my web application, the following code does not work:
protected void Page_Load(object sender, EventArgs e)
{
if (Page.IsPostBack)
Response.Write(locationSelector.SelectedLocationId);
// SelectedLocationId is null here!!!
}
When I run this code in the debugger, I see that my Page Load event fires before the Post Back event! Therefore, the data is not yet read from the postback. I know that using the MS provided text field control, the text is available at Page Load, so I think I must be doing something wrong.
How can I read the location that the user selected when the Page Load event fires? To clarify, I'm refering to the Page Load of a web application page.
You're setting SelectedLocationId on a postback event and at the same time you are trying to retrieve its value on the first load. SelectedLocationId will be null all right.
Try:
protected void Page_Load(object sender, EventArgs e)
{
if (locationSelector != null)
Response.Write(locationSelector.SelectedLocationId);
}
I'm using a Sharepoint WebPart to load a UserControl which has a button that does some processing on PostBack. I got a problem: when I click the button for the first time, the data loaded on ! IsPosback gets lost, but this does not occur when I click the button again. I think my problem is explained here: Sharepoint Lifecycle, but I haven't been able to find a workaround.
Any help would be really appreciated.
Additional Info:
I'm using EnsureChildControls on the WebPart's OnLoad event, and loading the UserControl on CreateChildControls.
I was able to fix this by programatically specifying an ID to the User Control.
E.g.:
protected void Page_Load(object sender, EventArgs e)
{
this.ID = "MyUserControlID";
}
More info here: http://bytes.com/topic/asp-net/answers/314816-dynamically-loaded-control-event-only-reached-2nd-postback
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
if (ViewState["MyStuff"] == null)
LoadMyStuffAndSaveToViewState();
else
DoSomethingWith(ViewState["MyStuff"]);
}
I have a user control, which is added to another user control. The nested user control is built up of a GridView, an image button and a link button. The nested user control is added to the outer control as a collection object based upon the results bound to the GridView.
The problem that I have is that my link button doesn't work. I click on it and the event doesn't fire. Even adding a break point was not reached. As the nested user control is added a number of times, I have set image button to have unique ids and also the link button. Whilst image button works correctly with its JavaScript. The link button needs to fire an event in the code behind, but despite all my efforts, I can't make it work. I am adding the link button to the control dynamically. Below is the relevant code that I am using:
public partial class ucCustomerDetails : System.Web.UI.UserControl
{
public event EventHandler ViewAllClicked;
protected override void CreateChildControls( )
{
base.CreateChildControls( );
string strUniqueID = lnkShowAllCust.UniqueID;
strUniqueID = strUniqueID.Replace('$','_');
this.lnkShowAllCust.ID = strUniqueID;
this.lnkShowAllCust.Click += new EventHandler(this.lnkShowAllCust_Click);
this.Controls.Add(lnkShowAllCust);
}
protected override void OnInit (EventArgs e)
{
CreateChildControls( );
base.OnInit(e);
}
protected override void OnLoad(EventArgs e)
{
base.EnsureChildControls( );
}
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
CreateChildControls( );
}
}
protected void lnkShowAllCust_Click(object sender, EventArgs e)
{
this.OnCustShowAllClicked(new EventArgs ( ));
}
protected virtual void OnCustShowAllClicked(EventArgs args)
{
if (this.ViewAllClicked != null)
{
this.ViewAllClicked(this, args);
}
}
}
I have been stuggling with this problem for the last 3 days and have had no success with it, and I really do need some help.
Can anyone please help me?
My LinkButton wasn't firing it's Click event, and the reason was I had its CausesValidation property set to True. If you don't want the link to validate the form, be sure to set this to False.
Try adding your click event to the linkbutton tag:
<asp:LinkButton runat="server" OnClick="linkShowAllCust_Click" />
Or adding it to your Page_Load:
Page_Load(object sender, EventArgs e)
{
this.lnkShowAllCust.Click += new EventHandler(this.lnkShowAllCust_Click);
}
Is the usercontrol within the gridview? If so register the event handler on the gridview's onrowcreated event.
It appears that you have a viewstate issue. Because the control isn't there when the viewstate is loaded the application doesn't know how to hook up the event to be fired. Here is how to work around this.
You can actually make your app work like normal by loading the control tree right after the loadviewstateevent is fired. if you override the loadviewstate event, call mybase.loadviewstate and then put your own code to regenerate the controls right after it, the values for those controls will be available on page load. In one of my apps I use a viewstate field to hold the ID or the array info that can be used to recreate those controls.
Protected Overrides Sub LoadViewState(ByVal savedState As Object)
MyBase.LoadViewState(savedState)
If IsPostBack Then
CreateMyControls()
End If
End Sub
I had the same issue. I had viewstate="false" on the page I was adding the control to. (on the aspx page)