.net - Set A Code Object As The DataSource For A ComboBox, Using XAML?
Sep 24, 2010
I've gotten to a point where I'm trying to add a ComboBox to a UserControl, and to populate it from a collection which exists in code.
I've been getting along pretty much on monkey-see-monkey-do coding for the most part; copying and adapting existing code in order to get the next stage working, but this DataSource stuff has me stumped. I've been through a whole bunch of articles on MSDN this morning and am no closer to understanding than I was when I started.
Let me go through a few of the things that are messing with me, and hopefully you guys will be able to point me in the right direction:
1) None of the [UserControlName].vb files contains any code. All of the code for the UserControls is stored in [UserControlName]Model.vb files, and then code of the following sort is used:
1.5) (using bullet points means I can't use <> brackets or code blocks later on. What the hell, markdown?) Anyway...
2) I'm pretty sure I only want a Static Source for the moment, as the items in the ComboBox aren't going to change during execution, at this time. Problem is, all the articles I can find about this are gigantic, complex things about creating XML readers, and populating DataGridViews and sorting data, and on and on and on. I just want to declare that I'm using a frealing List! A List I've already created in code.
So, yeah, I basically need to use a Public Property ComboBoxLines As List(Of String) from a class which isn't the same class as the UserControl itself as the DataSource for a ComboBox.
I use LINQ-to-Entities to populate the cmbGroup ComboBox
Dim db as myDataEntity cmbGroup.ItemsSource = db.Makes
How do I populate my second ComboBox (cmbModels) based on the selection of the first ComboBox (cmbMake) using XAML so that whatever I select in the first ComboBox automatically filters the ItemsSource in the second ComboBox?
here's what I'm trying to do:I have a Storyboard animation for an object done in Expression Blend. What I need is to be able to trigger that animation from the VB.net code
I've created a Custom Control, and I will be placing a large number of instances of that Custom Control on my xaml page. In working with that Custom Control in the VB Code Behind, how do I do the following?
How do I reference the name of the Custom Control (in my VB code) which was clicked with the MouseLeftButtonDown event? For example, if I have 10 instances of my Custom Control in xaml, each with a different x:name (say 1-10), when a particular instance is clicked, how can I see which one was clicked? I've tried a number of things including e.OriginalSource.Name (which returns the component within the control which was clicked and not the name of the instance of the control). My Custom Control consists of numerous parts and pieces (Rectangles, Lines, Text, etc). Each of these items is a part of my layer. In VB code, once I can reference a particular Control, how can I hide or change certain parts of that control (such as hiding a Line, and changing the text). Also, I need to modify more than just the control which was clicked, so I need to be able to access properties of all of the controls, not just what was clicked. For example, if I click Control instance Test1, I also need to modify Test2, Test3, and Test5 in some way.
Here is some test code I through together as part of a Silverlight project using MS Blend 2. My control is much larger, and I need 200 - 250 instances/copies of that custom control, so I really need to know which control instance/copy was clicked.
I wrote an ASPX file in VB.NET. Originally this file ran successfully but after adding one additional parameter it now fails on "Object reference not set to an instance of an object" on line "peType.DataSource = arrPEType" below.This error does not make sense to me though because I have similar parameter, 'dType', which it does not error on. What is the cause of this error?
Here is some of my ASPX code file: Sub Page_Load(Sender as Object, E as EventArgs) If Not IsPostback Then
I have defined a datagrid which has combobox in one of the columns, is there anyway to modify the datasource of the combobox (the source of the list) at run time?
I am trying to get the valuemember of my combobox but it just won't work. I have tried a lot of things (won't post them all here) can somebody just show me how to do this?
Private Sub cmbGroup_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmbGroup.SelectedIndexChanged ' Get valuemember here End Sub
I have a ComboBox that is bound to a List(of T).Now I type-cast the ComboBox.DataSource into List(of T)and add some more elements in the List.The items collection of the ComboBox doesnt get reflected and the new element does not show up in the ComboBox. Am I missing something ?
Private Sub UsernameEdit_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim sqlconn As New SqlConnection sqlconn.ConnectionString = "stuff"
[code]....
The combobox just populates with "System.Data.DataRowView" I know it is some command to read the correct data out of the table, is it setting up something like:
dim i as integer for i = 0 to CompanyNames.length-1 companyadapter.fill(companynames.rows(i)] next
just curious what happens when i set the datasource of a combobox or datagrid or what-not to a dt then when i want to change what's in the combobox etc., i just set the datasource to a new one. i am cleaning as i go but just want to know what happens to the old datasource:
I have a combobox which i am binding to a sortedDictionary list, so it displays in ascending order. My question is, I need to display "--Select--" as the first option. Is there any way to either:
1) add another item besides for the datasource
or
2) add an unsorted item to the top of the sortedDictionary
I have to add item "Final Grade" to my cboQuarter. The thing is, my cboQuarter already has a datasource and I can't add the item "Final Grade" during drop-down. The error says, "cannot modify or insert (can't remember word by word) when it already has a datasource."
I have a 2 classes, one is Employee, the other is Employees. Basically Employees is a collection of Employee, I have a combo box where the Datasource is Employees.
When the user selects a value from the combo box, How do I get an Employee object from whatever is selected?[code...]
Appropriate Title would be: Bind comboBox Tag to database.I have a comboBox on form which is bounded but and I need to populate it manually. With some reading on net i have found a way but it is not working
I can populate my combo, select item in combo, update database but the problem is when I load my form it displays empty combo (combo is fulled with my custom data but nothing is selected it must select correct ItemText) and after selecting a value in combo, the value disappears as soon as combo losses focus .
Is it possible to BOTH set a comboboxes datasource AND databind the selected value?Ihave 2 comboboxes on a form that I want to populate with data from 1 table,ut I want the actual selected values on each of the comboboxes to come from separate columns n another datasource Right now if one combobox changes, so does the other if that makes sense.
Here's a sample of code: 'Bind DataSource With cboYields
With code above, how do I assign the value to the combobox while retrieving data from the table so that it point to the corresponding combobox item. For example, if the value of status_ID is 1 then the combobox should show "completed" in the datagridview.
I am using code similar to this to populate a combobox with items from a database. The display works fine, but when I try to get the combobox.SelectedValue it is returning a DataRowView, where I need an integer. Obviously this is becuase I haven't casted the value to an integer, but the function, CInt(cboPosition.SelectedValue) is throwing an InvalidCastException. Is there any way that I can get the ValueMember's type to be an Integer?
Dim cn As New SqlConnection(CreditDisputesLogConn) Dim cmd As New SqlCommand("CustomersLookup", cn) Dim da As New SqlDataAdapter(cmd)
How can I get an item value from a Combobox using a datatable as it's datasource? Here's my code for constructing the combobox. This code works, that's why I'm not showing it all, but I want you to know how I'm creating the combobox.
Try query = "SELECT category_id, name FROM categories ORDER BY name ASC;" dbCommand = New MySqlCommand(query, dbConnection)
[Code]....
I want to display what is the item you physically see in the combobox that you select.
I have this controls ComboBox: list of myobject TextBox: view a description DataSource: list(of MyObject) MyObject:
property id as int property combodesctription as string property description as string
What I want: I set the datasource of combobox with list of MyObject when I select a value on combobox, I would like see description in TextBox is it possible bound text property of TextBox to same datasource of combobox or it is possible change description of TextBox only with changedEvent of ComboBox?
I have a ComboBox which is bound with a DataSource from (obviously) a Database. However, there are 659 different entries inside this Database and I was hoping to tack on AutoComplete.
I tried setting the Source to the ListItems since, after initialization and the data is bound, all the items necessary are in fact inside the ComboBox so I had assumed that it would pick that up. I was wrong. I tried using a Custom source but VS errored out saying that I couldn't do that since the ComboBox was bound.
My question is, how can I utilize AutoComplete's "Suggest" mode with a bound ComboBox?
I have a bound datagridview which populates from the database using parameters. I've added a combobox column through the datagridview properties. How do I access this combobox column datasource?
dbDataSet4 is a typed dataset. I want to learn how to use an Interface. The error message is suggesting using an IList. How would I do this. I'm having trouble finding good documentation on this.
I'm creating a dynamic combo box and adding to a form. I'm trying to fill the combo box with a DataSource from an ArrayList and then selecting an item in the combo box based off a value from a property.Problem is, the combo box items don't get bound until after the Form_Load event has finished and the form is visible. So the combo box is empty when I try to set the selected index of the combo box. See code for what I'm doing in detail, and refer to comments in
[code]...
How to select the right selected index for combo box without a hack (Load timer or something stupid like that)?
I am using a combobox which is connected by data source with a table. On this table I do a Select distinct with some filters. Everything is fine except the fact that when I click on the combobox and dont select a value the app hangs until I select one value.Sometimes I have this error, sometimes no.I call the value by the sub load:
I have a custom collection which is derived from a base class implementing IEnumerable and IEnumerator, this collection is populated with custom objects.I'm trying to set the datasource on a ComboBox on a WinForm to use the above collection - but when the code is run the ComboBox is always empty.
The code I was using was this:
Private Sub ViewSources_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load ' declaration Dim sourceCollection As SourceCollection Dim source As Source
