This one is really kicking my butt, i'm hoping someone can point me in the right direction.
I have a combobox on my form that i need to display a "yes" and a "no" instead of a "0" and "1" BUT to process a "0" and "1" depending on the selection. Make sense?
I have the 0 and 1 sitting in the Data > Items > Collection properties of the combobox.
I have tried playing around with the DisplayMember property and the ValueMember property but i cant seem to get these working.
Any ideas would be much appreciated!
In your Data > Items > Collection properties of the combobox
Delete every line in there and add the following, (in the same order)
NO
YES
Now double click on your combobox in the form in design mode.
In the event subroutine for the combobox - selected index changed event, add the following:
Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
UserChoseReloadSurvey = ComboBox1.SelectedIndex
End Sub
And that will save either a 1 or 0 in a variable named UserChoseReloadSurvey.
Taking it for granted that you have an integer variable named UserChoseReloadSurvey
Related
Private Sub comboBoxStudentID_SelectedIndexChanged(sender As Object, e As EventArgs) Handles comboBoxStudentID.SelectedIndexChanged
For Each dr As DataGridViewRow In Me.dataGridViewStudent.Rows
If dr.Cells(0).Value.ToString.Contains(comboBoxStudentID.Text) Then dr.Visible = True Else dr.Visible = False
Next
End Sub
I've created this method to check and display a row that contains the same Student ID as selected from the comboBoxStudentID the problem is it only checks the first row of the DataGridView. How can I make it check all of the rows if there is match of Student ID?
Without knowing how your data is organized, you could do this by binding the DataGridView and the ComboBox to the same data source. Since this is not specified and looking at the snippet of code (which appears to work) it appears to loop through the rows and if the currently selected combo box text is contained in the first column cell, then make that row visible. Otherwise make the row invisible.
The posted code appears to work however there is one scenario you may want to consider. If the combo box contains the values that are in column one of the DataGridView, THEN, when the user selects a value in the combo box, the DataGridView will display ONLY those values that match the current combo box selection. This appears to be what you are trying to do.
The problem is how do you re-display all the rows?
Once the combo box selection has changed to some value, the user can delete the selection but all the rows will not display unless you handle another event. Also this strategy is not very user intuitive. One possible solution (below) simply adds a top item of “Reset” to the top of the combo boxes items. Then when the user selects “Reset” all row will become visible. Hope this helps.
To reiterate: you should consider setting this up with a DataSource and possibly a BindingSource where this is done for you automatically. Just a thought.
Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
If ComboBox1.SelectedIndex > 0 Then
For Each dr As DataGridViewRow In DataGridView1.Rows
If (Not dr.IsNewRow) Then
If dr.Cells(0).Value.ToString.Contains(ComboBox1.Text) Then
dr.Visible = True
Else
dr.Visible = False
End If
End If
Next
Else
For Each row As DataGridViewRow In DataGridView1.Rows
row.Visible = True
Next
End If
End Sub
I'm having some trouble doing something that seems very simple but I just don't know what I'm doing wrong....
On Form_Load I populate a combobox with
Datasource
DisplayMember
ValueMember
Here I set .selectedindex = - 1 so that nothing is selected. The combobox gets populated properly and everything is bells and whistles.
Now when user selects something from the drop down, I want to populate a DataGrid with a bunch of info based off the VALUE selected. So I pass and ID into the function that populates the DataGrid.
I'm trying to do this like this...
Private Sub cbo1_SelectedValueChanged(sender As Object, e As EventArgs) Handles cbo1.SelectedValueChanged
dim productID as string=""
cbo1.SelectedValue = ProductID
Call PopulateProductGrid(ProductID)
End Sub
I also have tryined with SelectedIndexChanged, but for both event I get an error
Cannot set the SelectedValue in a ListControl with an empty
ValueMember.
I'll wager that the issue is that you're binding in the wrong order. You should always set the DataSource last, not first. Try changing that and see if your issue goes away. The problem is that setting the DataSource means that the control is bound, so an item will be selected and the appropriate events raised before you have set the DisplayMember and ValueMember.
In Visual basic i'm trying to make a field required by preventing the user to leave the active cell if it's empty.
The grid consists out of two columns. The first one is the ID which is automaticly filled in on adding a new row, the second one is the name.
On form load there are 4 items loaded into the grid. When the form is loaded the first cell that is selected passes the check with no problem. It is the same for the three cells that are filled on form load.
Unforunately it does not seem to work when i try to add a new row to the grid, enter a value and try to leave the cell. I've set a break point and checked the values. The value is equal to nothing... This is not the case with any of the already loaded values.
How does it not get the value i enter?
Thanks in advance.
Ivan.f
Private Sub ValidateCellValue(sender As Object, e As
DataGridViewCellValidatingEventArgs)
Handles grdResult.CellValidating
Dim catNaam = grdResult.Rows(e.RowIndex).Cells(1).Value
If IsNothing(catNaam) Then
MessageBox.Show("Veld mag niet leeg zijn")
e.Cancel = True
Exit Sub
End If
End Sub
I have vb 2008 Winforms application.
In my Branch form I have 11 textbox fields and I want to validate 8 of them, either mandatory, or required format such as UK postcode, UK tel nos etc.
My issue now is that when the validation starts, it is validating the last text field first ( or seems to be)
here is my code
For Each oCtrl As Control In Me.Controls
If TypeOf oCtrl Is TextBox Then
oCtrl.Focus()
If Validate() = False Then
Exit Sub
End If
End If
Next
what's wrong please?
what's wrong please?
The controls collection isn't sorted or grouped. Your loop will access them in whatever order the collection has them.
Without more code it's hard to say how to fix it. However a tip may be in order. Use the same handler to handle the validate event for each textbox. This way you can keep the user at that textbox until the input is valid.
is it possible to add the items to the collection in the order of their tab indexes on form Shown event, how would I do that please?
A List(Of TextBox) and a custom sorter would probably be the way to go
Dim AllTB As New List(Of TextBox)
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
AllTB.AddRange(Me.Controls.OfType(Of TextBox))
AllTB.Sort(Function(x, y) x.TabIndex.CompareTo(y.TabIndex))
End Sub
To loop through the textboxes use:
For Each tb As TextBox in AllTB
Because the TextBoxes are in the list by reference you can get or set any of the properties in the textboxes and any changes, will be reflected on your form. You could also use sequential names for the textboxes, tag property, etc. and sort by that.
I want to know what control to be use on my project is it Listview or listbox???. I have a comboBox control on my project what I want to do is when I selected 1 item on my combobox it will automatically add on listbox or listview and when I selected more than 1 item I want to add it on listbox or listview on newline...
Is it simple, please help me to do that in listbox or listview..thanks!
Listbox > Is for viewing too but user can select it
Listview > Is for viewing only, user cannot select also it viewing by five view directly cause it's for viewing only
If your project wanted the list to be viewing from what have been select by Combobox, then you just pick List View, but if you want for viewing also user can select it, better use listbox, so it's up to you.
Also you can know how the Tools work by focus your mouse cursor to the tool, then it will pop up an tooltip that write what the tool for.
Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
ListView1.Items.Add(ComboBox1.SelectedIndex)
End Sub
That is the code to viewing in listview for what you select in combobox
For clearing all the item in the Listview or listbox, just write to your form_load
Listview.items.clear
Why i said in form load, cause the list just for viewing, of course every time the form begin to run, it will need blank list, so the best is put in form load
UPDATE
To remove the selected index in listbox
Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
ListBox1.Items.Remove(ListBox1.SelectedItem)
End Sub
ListView Items can be selected a couple of ways In the Properties window for the ListBox the activation property allows an item to be activated by one click or two clicks. Here is an example of how the selected items can be used
If Me.ListView1.SelectedItems.Count = (1) Then
'Declare the selected item
Dim lviSelectedItem As ListViewItem = Me.listView1.SelectedItems(0)
'Now you can use it
lblLabel1.Text = lviSelecetedItem.Text
Else
lblLabel2.Text = "You can make Items selectable by switching CheckBoxes property to True in the Properties windows and using CheckBox event handlers"
End If