I'm working on a website that will allow instructors to report on the academic progress of students in their classes. I've got the website set up two primary pages: one with a user control that displays the classes (a GridView of basic class info with a child GridView in a template field that displays student names and checkboxes to select them -- called MiniStudents), and another with a user control that displays the selected students -- called FullStudents.
Although improbable, it's possible that an instructor could have the same student in two separate classes. I've already accounted for this in the current page setup -- the combination of student ID and class ID (class IDs change each quarter, for those thinking this will be an issue) form a unique key within the database. Recently, one of my users asked if I could break records out by classes on the page, so that instructors would be able easily recognize which class they're operating in.
So, my question is this: is it possible for me to dynamically add a column to the end of the class user control that would allow me to switch out MiniStudents for FullStudents?
If I've left out any important details or if anyone wants/needs code, please let me know.
Try this:
//Under page_load
string path;
if(condition) path = "~/MiniStudents.ascx";
else path = "~/FullStudents.ascx";
Control userControl = this.LoadControl(path);
panel1.Controls.Add(userControl);
And if you have specific properties that you want to set before the usercontrol gets rendered then make them inherit a custom usercontrol class:
public class CustomControl : UserControl
public class MiniStudents : CustomControl
public class FullStudents : CustomControl
So then you can do this:
CustomControl userControl = (CustomControl)this.LoadControl(path);
userControl.UserId = userId;
I hope this helps!
You could add both, and hide one or the other.
You could use a multiview control to control which control is visible. Though I would be concerned about your viewstate size if you are loading all these controls simulantously. It sounds like there could be a lot of data and markup on the page.
Related
I have created a class inherit from StateManagedCollection.
It has got a few class as Columns like GridView.
But I can not select which filed I want to select from.
It should look like the picture below in design.
But mine is the one below:
I have written the property as below:
[Description("A collection of ToolBarItem's ")]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
[Editor(typeof(System.ComponentModel.Design.CollectionEditor), typeof(System.Drawing.Design.UITypeEditor)), PersistenceMode(PersistenceMode.InnerProperty)]
public virtual Items Items
{
}
Can anyone help me out?
GridView columns collection uses a custom UI Type editor to show this interface. The in-built ASP.NET CollectionEditor will not show the required UI. Further in your case, CollectionEditor may not work if the collection's item type is a abstract class.
Solution is to build your own custom UI Type editor - basic steps are
Inherit from System.Drawing.Design.UITypeEditor.
Override GetEditStyle method to inform the property browser that you will launch modal form.
Override the EditValue method to launch your custom UI form.
Build the custom UI Form.
See a couple examples here (see sample for TagTypeEditor) and here.
Say I have a DetailsView with a bunch of fields, and I want only certain kinds of users to edit a few of them. They're too few to split them into another DetailsView, so what I'm thinking is to find some way to only allow a user to edit them based on some code-behind logic, effectively making them read-only at will.
I feel it's important to mention that the fields are both TemplateFields, not normal BoundFields with ReadOnly properties.
Any ideas? For some reason the required functions don't jump at me from reading the documentation.
Oh and I need eveyone to see their specific values, I just want to restrict edit access to them.
Hrm apparently it was as simple as setting the EditItemTemplate property of the fields in question to null. Seems to be working fine so far!
Edit: A short code sample showing how I did it:
foreach (DataControlField field in dvDRDetails.Fields)
if (!fieldstoignore.Contains(field.HeaderText))
if (field is TemplateField)
((TemplateField)field).EditItemTemplate = null;
else if (field is BoundField)
((BoundField)field).ReadOnly = true;
Where fieldstoignore is an array of field headers that I always have set as editable. The rest fall in two categories: TemplateField that require the hack I discussed above and BoundField that have a ReadOnly property I can set.
It is known that the ListView control can't display both an EmptyDataTemplate and a InsertItemTemplate at the same time.
For my design style I need to be able to show both. I want to be able to show that no data exist and at the same time show a form to add new data.
I've already implemented various solutions, such as putting a PlaceHolder in my LayoutTemplate and then manually showing or hiding this PlaceHolder in the code-behind, depending on if there is data or not.
However, I would like a control that has this built-in capability in order to keep my code-behind light.
I believe there are only two ways to achieve what I want:
First way (preferred) is to write that custom control myself. I was thinking of deriving from ListView and overriding the function responsible for disabling the EmptyDataTemplate, but I have no experience with custom controls. And I'm not even sure it will work in the end.
Second way is to use a custom control found or purchased somewhere. I have not been able to find such control that has the same base capabilities as the ListView.
Has anybody any idea how to solve #1 and maybe #2?
Thank you.
Here is what I ended up doing:
public class MyListView : ListView
{
protected override int CreateChildControls(IEnumerable dataSource, bool dataBinding)
{
int itemCount = base.CreateChildControls(dataSource, dataBinding);
if (this.InsertItemPosition != InsertItemPosition.None && itemCount == 0)
{
CreateEmptyDataItem();
}
return itemCount;
}
}
Works great!
I would go for your option 1: Create a custom control
Because you haven't specified a programming language I made one in VB.NET:
Public Class CustomListView
Inherits ListView
Public Sub CheckEmptyData() Handles Me.PreRender
If Me.Items.Count = 0 Then
Dim label As New Label
label.Text = "No data found <br/>"
Me.Controls.AddAt(0, label)
End If
End Sub
End Class
Just tested it and works perfectly, it can just replace an existing ListView.
As you can see it checks if there is any data and if not it inserts a label with the text "No data found". I haven't found an easy way to use the EmptyDataTemplate for this, that would be a better option but this might already work for you.
Another option is to hide the InsertItem (InsertItemPosition.None) if there is no data, and add a Button "Insert" to the EmptyDataTemplate that enables the InsertItemTemplate and therefore hides the EmptyDataTemplate.
I don't understand much of your requirement without a screen shot of what you are actually trying to achieve. Anyway, you may be able to achieve this interface with a combination of ListView+FormView or ListView+ a User Control. If you can provide any more info I may help further.
I have a structure that looks following
Class TreeNode {
public TreeNode Parent { get; }
public IEnumerable<TreeNode> Children { get; }
public . . . .
}
I want to bind this to a asp.net telerik radgrid with detail tables for each level of the children. I know that radgrid supports declarative binding to a self referencing hierarchy using a datasource control but that assumes you have a flat dataset (e.g. from a database) and can look at a parent key field of some sort. My question has anyone bound a radgrid to a data structure like this before and is there a way to do it declaratively or mostly declaratively?
I can't answer your question directly since I've no experience with the telerik grid, but I can offer a work around.
Add a method to your class that flattens its contents into a self-referencing table like structure such as the one you mentioned. This way you can still work with the class and it's more advanced structure like you want to, but can still output the contents in a consumable form that matches the expectations of the UI components.
This is also a good candidate for an extension method too.
Another possible way I can think of is to build the hierarchy dynamically by filtering the date for the child tables based on their parent inside the DetailTableDataBind grid handler. This demo is a good reference:
http://demos.telerik.com/aspnet-ajax/grid/examples/programming/detailtabledatabind/defaultcs.aspx
but I must agree that Stephen's suggestion might be more handy.
Dick
Ok, please understand the architecture here first.
OurMasterPage.aspx has user control Header.ascx
Header.ascx has a user control in it called LandingPageTopNav
LandingPageTopNav.ascx has a public property named "LandingPage" that is there to be able to set by the user using this control.
And I have a Third.aspx page in which I need to set the LandingPageTopNav property to a LandingPage object
The problem is that I can't get this to work in my ThirdPage.aspx.cs:
Master.LandingPageTopNav.LandingPage = this.landingPage;
Master.LandingPageTopNav.Visible = true;
And that is, I can't get the first line to work where I'm trying to reference the LandingPage property. The second line is fine. My Third.aspx definitely can reference my master page objects otherwise from code-behind.
I'd venture to guess that the LandingPageTopNav property of OurMasterPage doesn't return a value typed as LandingPageTopNav. It probably returns the correct control typed as something more generic (e.g. Control); which is why setting the Visible property works but not the LandingPage property.