Winform - SelectedIndexChanged Triggered Before ComboBox Populated?
Jan 27, 2011
When my form loads, before the ComboBox has been populated and selected this Event (SelectedIndexChanged) gets triggered. How can I prevent the code insides this Event from Executing before form has completely loaded? I tried testing for .SelectedIndex but it returns 0.
Let's say I have a DropDownList of product categories and a ListView of products based on the category selection in the DropDownList. When a user visits the page, there is a possibility of conconrency issue as new product belonging to a new category may be added to the inventory as the user is browsing.When the user selects a different category to view(a SelectedIndexChanged event) and causes a postback, I want the DropDownList to update the list of categories to include the new category being concurrently added and at the same time still able to make a change of selected index.
I have a form with a datarepeater that contains various controls (i.e. datetimepickers, text boxes, combobox) that are populated via a binding source. I also have other controls on the form that are not part of the data repeater. I would like to force validating all controls after the data is populated. I have successfully forced validating the non-datarepeater controls using Me.ValidateChildren() at the end of my load event. However, it does not fire the validating events for the controls within the data repeater. I have unsuccessfully tried many different attempts to set and move focus within the datarepeater controls trying to get the validating events kicked off. I am not sure where would be the best place (e.g. in drawItem? in ItemCloned?) to place the code and what it should be exactly.
Here was my latest attempt: Private Sub DataRepeater1_DrawItem(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.PowerPacks.DataRepeaterItemEventArgs) _ Handles DataRepeater1.DrawItem For i = 0 To e.DataRepeaterItem.Controls.Count - 1 e.DataRepeaterItem.Controls.Item(i).Focus() e.DataRepeaterItem.Controls.Item(0).Focus() Next
I successfully handled the validating events in the data repeater caused by user input errors. However, I have the unusual situation that the data coming into my form is already bad for some of the controls. The purpose of the form is to validate the data coming in to it and from user-input. I am newbie with vb.net.
What I want to do here is that for every new item added into the combobox the label will +1 from the previous number. How do I write it out assuming I didn't assign the items a number [Code]
I am using VB 2010 express edition, using windows form, i set my access database using the database connection wizard, and then use a combobox and bind it to the database using the properties windows, while other fields of database (set in textbox form), i drag it to my form. Running it, the values of textboxes are correct when i changed the value of my combobox. I want to use these values in textbox in drawing circle, whenever i change the value of combobox, the circle will also change using the combobox selectedIndexchanged event, my problem is, the value in textbox does not update in order to draw the circle, i have to use lostfocus or leave event to correct it. I make also a combobox and textbox not using this Ado.net(correct me if im wrong), it is working using the selectedindexchanged event only, what seems be my problem,
I have a ComboBox that contain ProductIDs and a DataGridView that lists Categories which a product can be a member of. My DataGridView list ALL categories, however, it has a checkbox column that get checked when the ProductID is a member of that Category, otherwise it is unchecked. A user may also check or uncheck a category checkbox then save.
The problem is, if a user forgot to save before changing the ComboBox, then his changes on the previous ProductID is gone How can I give the user a chance to either save or ignore the changes done on the previous ProductID (before selecting a new ProductID)?I searched the internet for an answer and I found the following code but it is in C# and I am not sure if it solves the problem or not!
What is the method to not allow combobox SelectedIndexChanged to be executed on load. and only make it to be executed when a "USER" changes the selection value.
I'm designing a login screen which MUST allow the user to ONLY select a login via a combobox. A user has THREE login attempts only, the problem Im experiencing is resetting the count if they hilight the combobox, move the selection around but ultimately click on the original name.I can use either SelectedIndexChanged or SelectionChangeCommitted but they are both activated even if the same login is selected.So you can select a login enter the password twice and then click on the combobox move the selection around before finally clicking the original name and the login count is reset to 0.Is their a way to do this without using variables to store the previous value (perhaps using validating/validation methods)?
I used the following code for displaying the data in datagridview according the to the selection from combobox1 and combobox4,, but the problem is that : it doesn't work perfectly with two comboboxes , it works only with the first combobox which be put.
In the context of data-bound combobox whose ValueMember and DisplayMember properties are appropriately set:Is there a difference between the SelectedIndexChanged and the SelecetedValueChanged events? Are they fired simultaneously when an item is selected from the drop-down list of the combo?
Can we stop the SelectedIndexChanged Event of combobox at runtime? bcoz when i go to last record my sencond combo is refreshed & It will show 1st Item. but i want to see related item with 1st combo.In the database records are stored with related item.but on frontend..
Amother question is, I want to work with Datagridcombobox. My datagrid contains 3 comboboxes. When i clicked on 1st ,2nd combo should be filled. Same like 2nd third. How can we handle the event of DatagridCombobox??
In my app I have a combobox and a sub wich handles the SelectedIndexChanged. It all works fine, but if the user goes crazy with the mouse scrollwheel changing the selected item in the combobox, the program will sometimes stop working for different reasons.
Now, what I want to do is to make some sort of sleep/wait function in the SelectedIndexChanged event handler, so that if the index hasn't changed in let's say 100 milliseconds, it will continue the code. If the index has changed, it will wait until the user has finished going crazy
What is the best solution to accomplish something like this? I've been thinking about using Thread.Sleep, but I can't find the correct way of doing it.
I am having a strang problem with button event handlers that I am creating at runtime.Actually if I set the form as startup form everything is working fine but when I set the main apllication form as startup form the events for buttons created at runtime are not firing.I am posting the code so that you can have a better look and see whts wrong?I have two classes under spotlight here "Class1" and "Grid"I am creating an instance of grid in class 1 and in a sub in grid I am creating buttons dynamically as follows and adding event handlers
For i As Integer = lIndex To uIndex Dim btn As New Button btn.Name = ds.Tables(tblName).Rows(i)(btnName).ToString
im wanting to add a new feature but am unable to even get started. I'm in a windows form in visual basic .net and basically, I have a combobox with 3 items in the drop down menu. I would like to make it to where the moment one of the items in the combo box are selected, the program recognizes the change of index and automatically calls to the function of my choice.
On my DataGridView one of the columns is set to a ComboBox. When I make a selection from this ComboBox the CellValue change Event is not triggered. What event is triggered when I do the selection?
send me sample code for SelectedIndexChanged event for Combobox , whn i change value in Combobox through SelectedIndexChanged event then data should be change in Other Combobox and Textbox.B`se i am tring a lot for this but last i am not able to get.In load Event i bind the data in Combobox control .
If All controls bind the same table then how can do code?? and if controls bind different tables then how can do code??
I'm using this line to populate my combobox with all files in my application path:
ComboBox1.Items.AddRange(IO.Directory.GetFiles(Application.StartupPath))This works fine, however it displays the path as well, and I only want to display the files with extension .txt
I'm trying to get a combobox to be automatically filled from a text file and have it editable by the user.
So far, when the program is running I can add new items and they appear in the text file and combobox but when I restart the program the combobox list is empty even though the text file has stuff in it.
Dim w As New IO.StreamWriter("z:url.list.txt") Dim linecounter As Integer For linecounter = 0 To ComboBox1.Items.Count - 1
I'm using visual basic 2008 express I have 1 combobox which is populated from a coloum from my database, when I select a value from the combobox I wish to populate several textboxes with data from the row selected. I have created a dataset. How can I do this? Is there a tutorial I can read anywhere
I have seen something like the following in many software. Combo box populated and displayed with multiple columns (for example stock code, stock description). But now I am only able to populate with stock code. May I know how to achieve this? I know it can be done by calling a form (And I can do whatever coding in this form) out when clicking on the combo box. But I am looking for better solution, or is it possible to populate the whole datagrid into the combo box as source instead of only the data.
I have a few reasons that I need this to happen, but suffice it to say that when I use the event handler for the RadioButtonList the sender object returns as just the RadioButtonList, and I need more information from the GridView because that's how I can uniquely identify which record my RadioButtonList is tied to.I added an "OnSelectedIndexChanged" property to my GridView but it doesn't fire/handle when I want it to. I'm assuming this has something to do with the way the GridView is designed to work. I also thought about using a hidden field, but I can't add it to the RadioButtonList so it won't help unless it's global. The problem with it being global is that I can't set the value uniquely to the record that has it's RadioButtonList being altered.
I'm just a beginner at VB.NET...I want to be able to insert a combobox control onto my form through code but I'm not sure how. Google doesn't seem to answer.
Something along the lines of (I have no idea) Me.AddControl("Combobox")
I would obviously then need to set the properties to setup the position/size etc.
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
A Form is to Accept User Name and Password from user, after verification the form should display another form that will accept user's full data. When a user press the Ok button, the information entered on this form should be display in another form (Showing the user what he/she has entered)
i have Design the Firs Form and the second form, how can i pass the information entered on the second form to third, and also what will the code look like I need help on this or Code Sample?
NB: i am trying create an instance of the second form in the third form and declare a variable in the third form that will holed the value, but still not working I want to learn .NET Programming in VC#, ASP.NET And VB.NET. I am student and really get excited when it comes to programming
I am using VS 2008 and UltraGrid from Infragistics v 5.2
I have two UltraGrid objects on a Winform. While the AfterRowUpdate event gets triggered for one, it does not get triggered for the other. Here's the procedure of the offending UltraGrid event:
This does get executed:
Private Sub ugPatient_AfterRowInsert(ByVal sender As Object, ByVal e As Infragistics.Win.UltraWinGrid.RowEventArgs) Handles ugPatient.AfterRowInsert e.Row.Cells("Courtesy_C").Value = "Mr."
[Code]....
The source file is different from when the module was built. Would you like the debugger to use it anyway?
Even if I rebuild by application, the dialog box does not go away.