Custom Server Controls :: Child Controls Of Extended GridView Rendering As Plain HTML?
Mar 7, 2011
I have been trying to implement an extended GridView that eventually will include a panel with a number of filter options outside of the grid iteself.
As a test I have added a dropdownlist and a linkbutton but when these are rendered to the page they are rendered as plain HTML with none of the javascript or ids that are generated for server controls as a consequence the postback event is not fired when a dropdownlist item changes and the linkbutton is rendered as plain text.
I have custom gridview that inherit from the regular gridview.
On of the features is that is has a built in page size dropdown in an extra header row.
Another feature is that this extra header row has a place holder where aditional controls can be added but here is where I have some problems.
When I add a control that is created outside the gridview to the gridviews builtin placeholder and tries to do anything that performs a postback the gridview dissepears, but appears again on a new post back.
Here is the code for the gridview:
[Code]....
And this is the way it is used in a usercontrol on page, the gridview is called gvList and the control that I try to add to its placeholder is the phrExtraHeaderControls:
[Code]....
What can be wrong, is the viewstate messed up in the postback so that the gridview can't be rendered?
I extended gridview control to add some new features and it is working fine. However, when i come to asp.net page and add the control declaratively, the templates of the parent control that is GridView are not visible.
I declare like following and then i cannot see all templates provided by GridVeiw itself such Columns, HeaderTemplate etc .
I am extending the GridView control to include a custom pager for a custom paging scheme (only one page returned from the database at a time rather than all records). In my testing a discovered an issue - on my last page of data, the GridView's rows property always returns a collection of PageSize page, rather than the actual number of records on the page, with non-data fill records being empty rows.
For example, suppose I have 23 records in my database. Assuming a PageSize of 10, when I page to the last page of data the gridview it properly displays the last 3 recrods - but when I handle the GridView's CommandName="Select" event the GridView's Rows collection contains 10 records, the last seven of which are empty.
I set a break point in just before I call GridView.DataBind and verified that the DataTable used as the DataSource for the last page of data does in fact only contain the 3 expected records. But when I set a breakpoint on the Sub that handles the "Select" GridView command, the GridView.rows collection contains 10 records, the last 7 of which are empty.
This post[URL] and comments make note of the issue but the solution prescribed by the author does not seem to work.
Attached are some snippets of my extended GridView and the two methods from my page where I mentioned setting breakpoints above.
I am creating custom server control. I have two classes in project. One is main class that render control and another will be used to render content based on condition.I just want to know how to render content from other classes in main class.For example. This isjust an example.My main class code
[Code]....
My TopLeftPane class
[Code]....
My page code on page load event
[Code]....
When I run the page, Header title always getting null. This is a just sample code. I will have more than 20 classes so I dont want to write a code in main class to render whole control.I hope all of you understand my problem.
I am trying to build a custom composite control, which allows me to add custom content to each child control. It's a similar concept to what you have with a GridView and TemplateColumn. The markup used to place the control on the page would end up being something like this:
[Code]....
I have the code below, which allows me to put that markup on the page without throwing any errors, and it renders all the correct HTML, except it doesn't render the contents of the ColumnTemplate. I have replaced the Render() code with a comment because it's quite long winded and doesn't add anything important here:
[Code]....
I have tried to follow examples on MSDN and other forums but I can't make this work. I think I'm missing the code to render the contents of the template, but I don't know how to hook that up.
I have a simple HttpHandler that generates a dynamic image based on query string parameters and a custom web control that renders an image tag pointing to the handler as its 'src' attribute. All works fine when run in the web server, but at design timethe control displays as the "missing image" icon (red x in a box). The handler is registered in the web.config with a ".ashx" extension. The RenderContents method in the control looks like this:
This way buttons are rendered on design view as well. The problem is that number of buttons to render is dynamic based on data in xml file (even if the data was static, the number of button is about 12 and I don't think it is wise to copy paste the same code above 6 times...). I thought by using loop for that:
int i = 1; foreach (Button button in tb.Items) { writer.AddAttribute(HtmlTextWriterAttribute.Type, "button"); writer.AddAttribute(HtmlTextWriterAttribute.Id, this.UniqueID + "butto_Foo" + i); writer.AddAttribute(HtmlTextWriterAttribute.Value, button.ButtonValue); writer.RenderBeginTag(HtmlTextWriterTag.Input); writer.RenderEndTag(); //button i++; }
tb is defined in OnLoad; On run time it works, but on design time I get error: > Error rendering control. And control is not being rendered.
I am using two user controls in my page. The controls are loaded dynamically one at a time. I'm just referencing the user controls in the page and loading them dynamically using 'LoadControl()'. Everything is working fine till now and the user can switch the controls one another.
Here the issue I found is eventhough the controls are working as expected and the data is visible, the rendered HTML contains only the first loaded user control's markup.
Even if the current control displayed is 'usercontrol2', the source shows 'usercontrol1' markup. How can I force the page to render 'usercontrol2' markup and remove 'usercontrol1' markup while loading'usercontrol2'?
I am trying to create a composite control - A textbox, gridview and a button. When I create the grid dynamically, I use my function GridViewDataBind() that will basically create the gridview at runtime and bind it with data. In this method, I add a blank column (first column for expand/collapse image), databound columns (using custom Itemtemplate), a placeholder, then a new html row/cell and a child gridview. I want to know how can I add these html rows/cols to my gridview. Here is the code:
[Code]....
Not sure if the approach is right and if I was able to explain my problem?
I have a custom ascx user control on my page that includes a dropdownlist. There is an nSelectedIndexChanged event handler that is connected to this dropdownlist. The first time the user selects a value, the page does a postback and the logic executes correctly. However, if the user then goes to change their selection, the event handler does not get triggered.
The method GetDesignTimeHtml of the ControlDesigner class should return html markup that will be shown on the page in design time. My problem is that control looks different in different versions of the visual studio. What is the rendering engine visual studio use to render control in design mode?
Here's my scenario, I want to add a confirm button for each delete link in a MVC app, so when I try this:
<%= Html.ActionLink("Delete", "Delete", new { id = item.Id }, new { id = "_delete_" })%> <asp:ConfirmButtonExtender ID="ConfirmButtonExtender1" runat="server" TargetControlID="_delete_" ConfirmText="Want it or not?" />
I get this:Exception Details: System.InvalidOperationException: The TargetControlID of 'ConfirmButtonExtender1' is not valid. A control with ID '_delete_' could not be found.
Problem is that the asp:ConfirmButtonExtender control is parsed before render happens, therefore no "delete" HTML control is present -
I have a server control which consists of a gridview with custom navigation&information capabilities and with javascript functions to highlight the selected grid items or highlight when mouse over event occurs.. (full tested outside asp:wizard)I'm trying to use that server control inside a template wizard step, when I drop such server control in the first step of the wizard everything goes ok.
When I insert even a blank step previous to the step which contains the server control, the javasript code of the server control is not rendered at all, the page doesn't fail during load but until I go with mouse over an item of the grid for instance.When I check the rendered HTML I can see no HTML, nor javascript events of this server control where rendered, neither the implementation nor calls to javascript, but even rarer what is there visible in the grid for ie, even the other components of the server control, are not in the "view source code" content. I seems it was sent to the client, even showed, but truncated in some phase..
I find it hard when using asp.net controls, to make proper css files because I don't know what the html output for the different controls end up as. For example, if I want to add a div tag using a asp.net control, it's not easy to know what kind of control I can use.
Are there any documentation that shows for each asp.net control, what the rendered html for that control will be? I understand that some controls will probably change it's output due to how it's configured, but most controls will at least follow a pattern here.
The best would of course be a service on the web where you can put in the asp.net control definition and get the rendered html out. Currently I have to put a control into my webform, run it and check the source in the browser, and if it's not the correct html tag, try another control and repeat. That get's tedious quite fast.
I have existing project written by someone else that utilizes custom User Control that among other things contains a GridView control.I'm working on implementing the bulk-edit function so that users can modify data in many rows at once and then update the database accordingly.My problem is that in all examples that I see in order to implement this functionality you need to Override the CreateRow method, at which point you are able to put it in Edit State. The issue is that since my custom control inherits from User Control and not from GridView this protected method is not available. If I change the inheritance to GridView, tons of other things break inside this code, so I'd like to avoid that.My question is, is there anyway to still override the CreateRow if I'm inheriting from UserControl class and not GridView.If this is not very clear, please let me know and I'll try to explain further. I really need help with this, as it is time sensitive and it's always hard to work with someone elses code,
I'm rewriting my website in aspx to pull text from a SQl server and pop it up in a modal. I have everything working fine, but when I was using plain asp and HTML tables, I was able to format some of the text in the database using HTML tags, and they would render to screen. Is there anyway to do the same thing when using the following:
I'm trying to develope a collapsible panel control with designer.
I have the following two classes:
[Code]....
and this one:
[Code]....
In fact, the designer class is a copy of a sample class in MSDN and I only tried to customize it to work for me. I'm not sure if all methods are necessary or not.
I have the following two questions:
1- When I use this contrl in design mode, I can add or delete controls to it, in the html view, tags are not updated. so when I close the page and open it again, all changes are lost.
2- I have added this control to the same asp.net project that is using this control. Isn't there any way to have this controil in tool box?