I want to ask how to control objects with a combobox in VB.
So I have a combobox with two choices On and Off.
How can I enable and disable a textbox with an combobox?
you can try something like this
private Sub OrainsComboBox3_SelectedIndexChanged(sender As Object, e As EventArgs) Handles OrainsComboBox3.SelectedIndexChanged
If OrainsComboBox3.SelectedText = "On" Then
OrainsTextBox7.Enabled = True
OrainsTextBox8.Enabled = True
End If
If OrainsComboBox3.SelectedText = "Off" Then
OrainsTextBox7.Enabled = False
OrainsTextBox8.Enabled = False
End If
End Sub
Related
I need a checkbox which will ask the user:"Do you need to add an address?" and if user clicks on it then address label and textbox appears on the form ( I mean By default they were invisible and then I have changed this state), I have implemented this functionality by CheckboxSate event but what if the user doesn't click on the checkbox at all, in this case after submission external details I am not able to move forward ( i mean after clicking on the next button my form don't call another subform, but when I check/uncheck checkbox it works correctly), is there any way to edit/update form validation or any default checkbox property in order to get rid of this bag?, here is my CheckState Event's code:
Private Sub AddAddress_CheckedStatrChange_1(sender As Object, e As EventArgs) Handles AddAddress.CheckStateChanged
If AddAddress.CheckState = CheckState.Checked Then
AddAddressLabel.Visible = True
AddAddressTextBox.Visible = True
AddAddressTextBox.Enabled = True
ElseIf AddAddress.CheckState = CheckState.Unchecked Then
AddAddressLabel.Visible = False
AddAddressTextBox.Visible = False
AddAddressTextBox.Enabled = False
End If
END Sub
That's how you would do:
Sub AddFTP_CheckedChanged() Handles AddFTP.CheckedChanged
AddAddressLabel.Visible = Not AddAddressLabel.Visible
AddAddressTextBox.Visible = Not AddAddressTextBox.Visible
AddAddressTextBox.Enabled = Not AddAddressTextBox.Enabled 'It's useless since it's not visible
End Sub
I'm using ToolStrip and it's buttons to change GUI structure with an example code how i change GUIs with tool strip buttons. Are there any methods to use them more easy way like when clicked event of ToolStripButton handled it can call a single procedure etc.? In current case it seems i'm coding in a bad way.
For example if user click the Home button it highlights the button as selected and hides other panel elements and make visible Home's panel.
Private Sub tsbHome_Click(sender As Object, e As EventArgs) Handles tsbHome.Click
tsbHome.Checked = True
tsbTools.Checked = False
tsbReport.Checked = False
tsbAnalyze.Checked = False
'... Tool Strip Button lists continues...
pnlHome.Visible = True
pnlTools.Visible = False
pnlReport.Visible = False
pnlAnalyze.Visible = False
' ... Panel lists continues...
End Sub
if user click the Tools button it highlights the button as selected and hides other panel elements and make visible Tool's panel.
Private Sub tsbTools_Click(sender As Object, e As EventArgs) Handles tsbTools.Click
tsbHome.Checked = False
tsbTools.Checked = True
tsbReport.Checked = False
tsbAnalyze.Checked = False
'... Tool Strip Button lists continues...
pnlHome.Visible = False
pnlTools.Visible = True
pnlReport.Visible = False
pnlAnalyze.Visible = False
' ... Panel lists continues...
End Sub
There are two tricks to making this code much simpler. The first is knowing you can have more than one item in the Handles clause of an event method declaration. (You can also omit that clause, and use AddHandler to set up event handlers for a lot of controls to one method.) The other trick is knowing how to use the sender argument to determine which of the several controls connected to this method was used.
Put those together, and you get one method that will work to change to any of your views.
Private Sub NavigationMenuItem_Click(sender As Object, e As EventArgs) Handles tsbHome.Click, tsbTools.Click, tsbReport.Click, tsbAnalyzer.Click
'First Suspend Layout, to avoid extra screen re-draws
Me.SuspendLayout()
'Set your checkboxes
tsbHome.Checked = sender Is tsbHome
tsbTools.Checked = sender Is tsbTools
tsbReport.Checked = sender Is tsbReport
tsbAnalyze.Checked = sender Is tsbAnalyze
'Then De-select EVERYTHING
pnlHome.Visible = sender Is tsbHome
pnlTools.Visible = sender Is tsbTools
pnlReport.Visible = sender Is tsbReport
pnlAnalyze.Visible = sender Is tsbAnalyze
' ... lists continues...
'Finally, resume layout so all changes draw to the screen at once
Me.ResumeLayout()
End Sub
We can make this simpler if you add code to the Form Load or InitializeComponent() method to put the panels and toolstrip buttons into lists:
Private ViewButtons As List(Of ToolStripButton)
Private ViewPanels As List(Of Panel)
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
ViewButtons = New List(Of ToolStripButton) From {tsbHome, tsbTools, tsbReport, tsbAnalyze}
ViewPanels = New List(Of Panel) From {pnlHome, pnlTools, pnlReport, pnlAnalyze}
For Each b In ViewButtons
AddHandler b.Click, AddressOf NavigationMenuItem_Click
Next
End Sub
Private Sub NavigationMenuItem_Click(sender As Object, e As EventArgs)
Me.SuspendLayout()
For i As Integer = 0 To ViewButtons.Length - 1
Dim selected As Boolean = ViewButtons(i) Is sender
ViewButtons(i).Checked = selected
ViewPanels(i).Visible = selected
Next
Me.ResumeLayout()
End Sub
Iam trying to get DataGridView rowIndex and set it to textbox and all is well with this code
Private Sub dgv_CellContentClick(sender As Object, e As DataGridViewCellEventArgs) Handles dgv.CellContentClick
isitxt(e.RowIndex)
btnInsert.Enabled = False
btnUpdate.Enabled = True
btnDelete.Enabled = True
End Sub
and
Sub isitxt(ByVal x As Integer)
txtIDBarang.Text = dgv.Rows(x).Cells(0).Value
txtNamaBarang.Text = dgv.Rows(x).Cells(1).Value
cbJenisBarang.Text = dgv.Rows(x).Cells(2).Value
numHargaBeli.Value = dgv.Rows(x).Cells(3).Value
numHargaJual.Value = dgv.Rows(x).Cells(4).Value
End Sub
But i got IndexOutOfRangeException when i clicked on Column Header. how can i handle it ?
Note, that if you use CellContentClick, the code will be executed only if the user actually aims at text content of a cell. Usually a CellClick is makes more sense.
As for your code, you can debug and see, what's in "x", when you get an error - I guess "-1"... You can handle it then. However, the reason for this should not be in your code above.
You can also set SelectionMode = FullRowSelect and do it following way:
Private Sub dgv_CellClick(sender As Object, e As DataGridViewCellEventArgs) Handles dgv.CellClick
isitxt(Me.dgv.selectedRows(0).index)
btnInsert.Enabled = False
btnUpdate.Enabled = True
btnDelete.Enabled = True
End Sub
Unless you want to handle the cells separately, users usually prefer the FullRowSelect mode.
I have two checkboxes for two groupboxes to enable visibility or invisibility of each one at a time but somehow one is working(chboNew) the other one(chboIssue) doesn't!
here is the code I have written for it, any help would be appreciated:
Private Sub chboIssue_CheckStateChanged(sender As Object, e As EventArgs) Handles chboIssue.CheckStateChanged
If chboIssue.Checked = True Then
gbIssueSearch.Visible = True
gbNewSearch.Visible = False
chboNew.Checked = False
ElseIf chboIssue.Checked = False Then
gbIssueSearch.Visible = False
End If
End Sub
Private Sub chboNew_CheckStateChanged(sender As Object, e As EventArgs) Handles chboNew.CheckStateChanged
If chboNew.Checked = True Then
gbNewSearch.Visible = True
gbIssueSearch.Visible = False
chboIssue.Checked = False
ElseIf chboIssue.Checked = False Then
gbNewSearch.Visible = False
End If
End Sub
If user has to choose between new issue and issue search,one at a time.
Then you should use radio buttons, instead of checkbox.
Checkbox gives idea that user can choose both checkboxes at same time.
Which in your case is not true.
Changing the name of the checkboxes is not going to solve your issue. I noticed that for your chboNew.CheckStateChanged event handler in your elseif clause you are checking if chboIssue is checked, whereas in your other handler for chboIssue both your if/else clauses look at chboIssue. I'm thinking that may be part of your issue. Also, if only one of these boxes is supposed to be checked at a time, you may want to add logic to automatically uncheck the other whenever one is checked. For instance, in your chboNew handler, "If chboNew.Checked = True Then chboIssue = False", and the inverse in your chboIssue handler. Hope this helps.
I know this seems like an easy fix, but I am having trouble. I have a CheckBox, when checked, I remove the data source of a DataGridView on my Windows Form and remove the ReadOnly properties of a few Textbox.
I know the CheckedChanged event will send my code into an infinite loop, but I cannot figure out which event would handle this change without changing the CheckedState each time. I have tried using Click, MouseClick, and CheckStateChanged events with no luck.
This is my current code:
Private Sub chkManual_MouseClick(sender As Object, e As EventArgs) Handles chkManual.MouseClick
If Not Me.chkManual.Checked Then
Me.chkManual.Checked = False
Me.cbRegion.SelectedIndex = -1
Me.txtIssueDate.ReadOnly = True
Me.txtCasenum.ReadOnly = True
Me.txtCommnum.ReadOnly = True
Exit Sub
Else
Me.dgDataEntry.DataSource = Nothing
Me.cbRegion.SelectedIndex = -1
Me.txtIssueDate.ReadOnly = False
Me.txtCasenum.ReadOnly = False
Me.txtCommnum.ReadOnly = False
ClearForm()
frmPDF.Hide()
Exit Sub
End If
End Sub
Properties of CheckBox: AutoCheck = True, Checked = False, and CheckState = Unchecked
I have looked into these already:
CheckBox_Checked event
Is there a simpler way to process check boxes?
CheckBox reverts to checked after being unchecked
How to check if a checkboxes state has changed
How can I prevent an assignment statement to CheckBox.Checked from raising the CheckChanged event?
http://www.vbforums.com/showthread.php?758455-CheckBox-code-got-stuck-in-an-infinite-loop-can-not-unchecked-it
EDIT
It helps if your ClearForm() sub doesn't change the CheckedState of your CheckBox back to False every time. Thank you #Visual Vincent for pointing out the obvious. Nothing is wrong with the code, changed the EventHandler to CheckedChanged
Final code (so simple):
Private Sub chkManual_CheckedChanged(sender As Object, e As EventArgs) Handles chkManual.CheckedChanged
If Me.chkManual.Checked Then
Me.dgDataEntry.DataSource = Nothing
Me.cbRegion.SelectedIndex = -1
Me.txtIssueDate.ReadOnly = False
Me.txtCasenum.ReadOnly = False
Me.txtCommnum.ReadOnly = False
ClearForm()
frmPDF.Hide()
Else
Me.cbRegion.SelectedIndex = -1
Me.txtIssueDate.ReadOnly = True
Me.txtCasenum.ReadOnly = True
Me.txtCommnum.ReadOnly = True
End If
End Sub
I'm not sure if you want the CheckBox, when Checked, to Uncheck again automatically or not!?...seems like a weird interface.
At any rate, if you want something to occur when the Check state changes:
Private Sub chkManual_CheckedChanged(sender As Object, e As EventArgs) Handles chkManual.CheckedChanged
If chkManual.Checked Then
Debug.Print("Checked")
Me.dgDataEntry.DataSource = Nothing
Me.cbRegion.SelectedIndex = -1
Me.txtIssueDate.ReadOnly = False
Me.txtCasenum.ReadOnly = False
Me.txtCommnum.ReadOnly = False
ClearForm()
frmPDF.Hide()
Else
Debug.Print("UnChecked")
Me.cbRegion.SelectedIndex = -1
Me.txtIssueDate.ReadOnly = True
Me.txtCasenum.ReadOnly = True
Me.txtCommnum.ReadOnly = True
End If
End Sub
You can uncheck the checkbox without an infinite loop like this:
Private Sub chkManual_CheckedChanged(sender As Object, e As EventArgs) Handles chkManual.CheckedChanged
Static counter As Integer
If chkManual.Checked Then
counter = counter + 1 ' just to show we're not in an infinite loop...
Debug.Print("Checked " & counter) ' just to show we're not in an infinite loop...
chkManual.Checked = False
Else
Debug.Print("UnChecked")
End If
End Sub
Not sure why you'd want to do that...seems like that would basically be a "reset" button as it couldn't stay in a checked state...
Can you remove the code that changes the checkbox state? Ex:
Me.chkManual.Checked = False
The box will check or uncheck without your code having to do it, and the event will only throw once.
I think the easiest way is to remove event listener before handling checkbox checked state. Use try-finally block to ensure that checkbox event listener is always set back.
Try
RemoveHandler chkManual AddressOf chkManual_MouseClick
Me.chkManual.Checked = False
...
Finally
AddHandler chkManual AddressOf chkManual_MouseClick
End Try