I have a database that I am using in a VB 2010 project. What I did was removed a textbox for a database field that I dragged onto the form and replaced it with a combobox. The field name was orderstatus.
The problem is this: since I removed the textbox field from the form, I can't seem to bind the combobox value to the field in the active record. In other words, orderstatus textbox doesn't exist anymore. I want to let the user pick a status from the combobox and store that value to orderstatus so that it's saved to the current record my database.
I want to do something like this:
Private Sub Button16_Click_1(sender As System.Object, e As System.EventArgs) Handles Button16.Click
orderstatus = ComboBox13.SelectedValue
Me.OrdersDataSet.orders(0).orderstatus = orderstatus
Me.Validate()
Me.OrdersBindingSource.EndEdit()
Me.TableAdapterManager12.UpdateAll(Me.OrdersDataSet)
End Sub
but it doesn't like my second line where I try to assign the value to the field, saying there is no row 0. All I want to do is put the selected value of the combobox into the orderstatus field of the record being created (or updated).
I've also tried using:
Me.OrdersDataSet.orders.orderstatusColumn = orderstatus
and I get a message saying that the property of the column is ReadOnly. I'm not sure how that's possible because I configured the dataset to update, etc.
I should probably mention that I'm not using a datagridview but a details view, if that makes a difference. I've seen some talk about how to do this using datagridview and don't know if that would work in my case.
What am I doing wrong? What should I use to update just the column I want in the current row?
Ugh, turns out I had forgot to set the databinding properties of the field in question to save directly to the binding source and also select the selecteditem to bind. It was right there and I didn't realize. Ya live and learn. :)
Related
I have a combobox that is of type dropdown, i.e. allows user to either select something from the list or to type in a new value. Based on this combo value, other values are selected in the form automatically as they are databound.
Customer_ID is the field that needs to be picked or typed in, and based on it Customer first name and second name are updated in the form automatically. This works fine if I pick some value from dropdown, lets say Customer Id = 1111.
Now in place of picking, if i type in this value and press tab, no udpate happens on the Name fields. Please suggest what am I missing here.
I think the best you are going to do with the standard ComboBox is to handle the Leave event, or possibly the TextChanged event. I did some experimenting and typing in a value does not add to the list, it just changes the Text property. It doesn't even change the value of the item you typed over. And, it doesn't fire SelectedItem or IndexChanged events.
So if you handle the Leave event, you have a place to do your lookup when someone tabs off the ComboBox. But the item won't get added to the list.
If you need functionality not provided in the default control, you could redesign your UI with perhaps a TextBox and Button that add an item. Or, you could look for third party implementations of ComboBox controls that would have more functionality.
Private Sub ComboBox1_Leave(sender As Object, e As EventArgs) Handles ComboBox1.Leave
Dim theCB As ComboBox = DirectCast(sender, ComboBox)
DoLookup(theCB.Text)
End Sub
I have a vb.net 2010 form with 22 data bound controls from two tables held in a dataset which is navigated by a bindingnavigator. This successfully adds deletes and updates. However what I need is when adding a new record I need some of the fields to be pre filled out. More specifically I have points balance fields etc which could be any value but will normally be 0 on a new customer so I want to initialise them to 0 when adding new records.
I located an AddingNew event on my datasource but this is called before the new item is added and thus all my initialisation is lost.
any help on this would be appreciated.
kind regards
Feldoh
Since you are using DataTables, you can manually set the DefaultValue property of the DataColumn:
Dim dt As New DataTable
Dim dc As New DataColumn("test", GetType(String))
dc.DefaultValue = "hello"
dt.Columns.Add(dc)
dt.Rows.Add()
Debug.WriteLine(dt.Rows(0)("test").ToString)
Result: hello
Answer including multiple linked tables solution:
Like LarsTech said using
dataset.table.Columns.Item("someField").DefaultValue = someValue
works nicely if you have a standard default but it also works for generated defaults, if you reset this default on saving to the next value you want if a new addition is made. However if you are using a dataset as your data source where a child table record cannot feasibly be generated (like in my case where an account id will be generated only on saving using a database trigger to link all different kinds of accounts) you can still set defaults for the other fields, the ones from the sibling (or non-existent parent) table but
dataset.siblingTable.Columns.Item("someField").DefaultValue = someValue
WILL NOT WORK as the binding navigator only generates the first sibling and the parent is not generated until the trigger. However on the BindingSource.PositionChanged event of the binding source that IS generated by clicking add you can freely put defaults into the actual controls on the screen and they will not be overwritten by nulls, clearly you need to restrict this so it only happens if the user pressed add by adding a variable to the Clicked event of the add button to tell you when add has been clicked and resetting this variable on save or roll-back. It is also possible to modify the bindings themselves which have an if null or empty default value.
Hope this helps someone else :)
Use the MouseUp event on the 'Add Row' button in the BindingNavigator instead of the "Click" event. This is becouse the new ROW does not exist in the datagridview until AFTER the click event is completed.
Private Sub BindingNavigatorAddNewItem_MouseUp(sender As Object, e As MouseEventArgs) Handles BindingNavigatorAddNewItem.MouseUp
'works with add row from the binding navigator
myDataGridView.Item(3, myDataGridView.CurrentRow.Index).Value = txtDefaultDescrip.Text.Trim
End Sub
to do this same thing when adding data directly in you DataGridView do this.
Private Sub myDataGridView_DefaultValuesNeeded(sender As Object, e As DataGridViewRowEventArgs) Handles myDataGridView.DefaultValuesNeeded
'works with add row inside a datagridview
e.Row.Cells(3).Value = txtDefaultDescrip.Text.Trim
End Sub
In this example I have a editable default value shown on my from. If you have a non-changing default value (e.g., is always 1 for column 3) then you should do that when setting up your datasource.
I'm using an Infragistics UltraWinGrid with a column of drop-down boxes. I don't want the user to be able to select the same value for multiple rows in that column. Is there a simple (or heck, I'd settle for advanced) way to do this?
I'm using VB.NET
-EDIT-
I tried setting a filter on the data source for the drop-down box. But when I did that, the values in the other boxes in that column started disappearing (not the values themselves, but the descriptions that they were supposed to represent, so instead of reading "Information", it just said "1"). All of the cells in a column refer to the same combo box, so if you filter out a value from the data source for one of them, you filter it out for all of them.
I'm currently trying to catch a CellChange event and check against all other currently-used values. If it was already used, I would put up a message saying as much and revert back to the old value. However, the value comes back as the previously-saved one, so... not helpful. About to see if I can use the "text" property.
Since you're using Infragistics, you could use an UltraDropDown which is bound to a DataTable (or something similiar) which you can add a "Selected" column in addition to a column holding the values you want to show.
As each value is selected (via AfterCellUpdate or AfterCellListCloseUp for instance), you could update the "Selected" column in that data source and use a column filter to only show items which haven't been marked as selected. That way as items are selected or removed, the contents of the drop-down would be automatically updated.
To clear the selected flag from the old value, you can use the BeforeCellUpdate event to access the cell's current value then perform a lookup on the data source bound to the UltraDropDown using that value to clear the flag.
Solved it:
The trick was to use BeforeCellUpdate whose BeforeCellUpdateEventArgs has a "NewValue" and a "Cancel" member. I just look through all of the items in the column to see if any of them match the new value. If one does, I notify the user and cancel the operation.
And that's it. Here's the code:
Private Sub myUltraWinGrid_BeforeCellUpdate(ByVal sender As Object, ByVal e As Infragistics.Win.UltraWinGrid.BeforeCellUpdateEventArgs) Handles myUltraWinGrid.BeforeCellUpdate
If e.Cell.Column.Key = "myColumn" Then
Dim newValue As Integer = CInt(e.NewValue)
For Each row As Infragistics.Win.UltraWinGrid.UltraGridRow In myUltraWinGrid.Rows
If row.Cells("myColumn") IsNot e.Cell _ 'So I'm not checking against the current cell
AndAlso CInt(row.Cells("myColumn").Value) = newValue Then
MsgBox("That value has already been used in this column")
e.Cancel = True
End If
Next
End If
End Sub
I have some controls bound to a BindingSource control.
I want to do a calculation when the value changes in one control and set the result on another control.
Do I update the textbox the property is bound to or do I update the underlying entity which would update the control anyway (I hope)?
When I change combobox A (OnPropertyChange) textbox B is updated with the new calculated result. This works fine, but I have noticed that when I leave combobox A it reverts back to its original value. What is going on here!
Private Sub ComboBoxEditCostCode_EditValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBoxEditCostCode.EditValueChanged
Select Case ComboBoxEditCostCode.EditValue
Case "7"
CType(TransactionEntityBindingSource.Current, TblTransactionsEntity).Qbdescription = "7-is here"
Case "2"
CType(TransactionEntityBindingSource.Current, TblTransactionsEntity).Qbdescription = "2-is here"
Case Else
CType(TransactionEntityBindingSource.Current, TblTransactionsEntity).Qbdescription = "7-is here"
End Select
End Sub
if we bind a control to a source, then if the source changes, we can make the its value automatically reflected in the control. About the problem you are facing, it would be better if you show the code snippet.
Tell more about your changing, how second text box is bound?
You have to change your initial data instead of changing textbox b value.
Also when textbox A loses it focus raises EndEdit event and I think binding mechanism refreshes value in textbox B.
You can control on which action editing is done when you setting your binding to textboxes.
as a rule of thumb, if you are using a binding source you always CRUD the data through it. Don't forget to call BindingSource.EndEdit when you are done, hope this helps
I'm currently creating a WinForm in VB.NET bound to an access database.
Basically what i have are two forms: one is a search form used to search the database, and the other is a details form. You run a search on the searchForm and it returns a list of Primary Keys and a few other identifying values. You then double click on the entry you want to view, and it loads the details form.
The Details form has a collection of databound controls to display the data: mostly text boxes and checkboxs. The way i've set it up is i used the UI to build the form and then set the DataBindings Property of each control to "TblPropertiesBindingSource - " where value name is one of the values in the table (such as PropertyID or HasWoodFloor).
Then, when you double click an entry in the searchform, I handle the event by parsing the Primary Key (PropertyID) out of the selected row and then storing this to the details form:
Note: Detail is the details form that is opened to display the info
Private Sub propView_CellDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles propView.CellDoubleClick
Dim detail As frmPropertiesDetail = New frmPropertiesDetail
detail.id = propView.Rows(e.RowIndex).Cells(0).Value
detail.Show()
End Sub
Then, upon loading the details form, it set's the filter on the BindSource as such:
TblPropertiesBindingSource.Filter() = "PropertyID=" & id
This works great so far. All the controls on the details form will display the correct info. The problem is updating changes.
Scenario:
If i have the user load the details for say, property 10001, it will show a description in a textBox named descriptionBox which is identical to the value of the description value of for that entry in the database. I want the user to then be able to change the text of the text box (which they can currently do) and click the save button (saveBut) and have the form update all the values in the controls to the database.
Theorectically, it should do this as the controls are DataBound, thus i can avoid writing code that tells each entry in the database row to take the value of the aligned control.
I've tried calleding PropertiesTableAdapter.Update(PropertiesBindingSource.DataSource), but that doesnt seem to do it.
Ok, I was able to figure this out picking apart some code I pillaged from a friend.
Everything was ok, the problem was the updating
When I was saving the data, i was calling just:
Me.TblProptertiesTableAdapter.Update(Me.TblPropertiesBindingSource.DataSource)
The correct code, without changing anything else is:
Me.Validate()
Me.TblPropertiesBindingSource.EndEdit()
Me.TblPropertiesTableAdapter.Update(Me.RentalPropertiesDataSet.tblProperties)
Me.RentalPropertiesDataSet.AcceptChanges()
Where RentalPropertiesDataSet is the database where TblProperties comes from. Inorder for this to work, make sure TblPropertiesBindingSource.DataSource is RentalPropertiesDataSet.Properties This was autosetup for me by VS08 when it created the BindingSource.
Basically, I needed to tell teh BindingSource to stop allowing the fields to be edited. Then we save the changes to the database, and lastly we tell the DataBase to accept the changes.