I work on Visual Studio 2019, on a WindowsForms Project.
my problem is that i just can drag and drop items upwards but if i move items downwards the program crashes.
Private Sub ListBox1_DragDrop(sender As Object, e As DragEventArgs) Handles ListBox1.DragDrop
ListBox1.Items.Insert(ListBox1.IndexFromPoint(ListBox1.PointToClient(New Point(e.X, e.Y))), e.Data.GetData(DataFormats.Text))
ListBox1.Items.RemoveAt(ListBox1.SelectedIndex)
End Sub
Private Sub ListBox1_DragOver(sender As Object, e As DragEventArgs) Handles ListBox1.DragOver
e.Effect = DragDropEffects.Move
End Sub
Private Sub ListBox1_MouseDown(sender As Object, e As MouseEventArgs) Handles ListBox1.MouseDown
ListBox1.DoDragDrop(ListBox1.Text, DragDropEffects.All)
End Sub
Edit: this is the error I get:
System.ArgumentOutOfRangeException: "InvalidArgument=Value with the value -1 is invalid for the index.
Just check to make sure your index isn't at -1:
Private Sub ListBox1_DragDrop(sender As Object, e As DragEventArgs) Handles ListBox1.DragDrop
Dim index As Integer = ListBox1.IndexFromPoint(ListBox1.PointToClient(New Point(e.X, e.Y)))
If index > -1 Then
ListBox1.Items.Insert(index, e.Data.GetData(DataFormats.Text))
ListBox1.Items.RemoveAt(ListBox1.SelectedIndex)
End If
End Sub
Related
I have a windows form application which added string into list of collection. This can be done by input the string into the textbox then click 'add' button, and the list will display in a listbox.
Now, I want to delete the last item in the list collection & the listbox.
Below are the code snippett that I have done
Public strList As List(Of String) = New List(Of String)
'add string to list
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
If TxtBox.Text <> "" Then
strList.Add(TxtBox.Text)
TxtBox.Clear()
End If
lstItem.Items.Clear()
strList.ForEach(AddressOf ListItem)
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
lstItem.Items.Clear()
strList.ForEach(AddressOf ListItem)
End Sub
'Add item into list
Public Sub ListItem(s As String)
lstItem.Items.Add(s)
'lstItem.Sorted = True
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
strList.ToList.ForEach(AddressOf DeleteItem)
End Sub
'Delete item
Public Sub DeleteItem(s As String)
For i = 0 To strList.Count
lstItem.Items.RemoveAt(strList.Count - 1)
i = i + 1
Next
End Sub
as you can see, in the sub DeleteItem, i try to delete the last item of the list collection by clicking 'delete button'. but the error says Additional information: InvalidArgument=Value of '1' is not valid for 'index'.
can anyone help me on this? thank you.
What you really ought to do is use a BindingList(Of String) and bind it to the ListBox. That way, you only have to deal with one list. Adding and removing against the underlying BindingList will automatically affect the ListBox:
Private items As New BindingList(Of String)
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
ListBox1.DataSource = items
End Sub
Private Sub addButton_Click(sender As Object, e As EventArgs) Handles addButton.Click
items.Add(TextBox1.Text)
End Sub
Private Sub deleteSelectedButton_Click(sender As Object, e As EventArgs) Handles deleteSelectedButton.Click
items.RemoveAt(ListBox1.SelectedIndex)
End Sub
Private Sub deleteLastButton_Click(sender As Object, e As EventArgs) Handles deleteLastButton.Click
items.RemoveAt(items.Count - 1)
End Sub
I'm writing a VB program that has multiple positions where when the user hovers over an item, the same image appears.
Currently I have:
Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove
PictureBox1.Image = Image.FromFile(picturePath)
End Sub
Private Sub PictureBox2_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox2.MouseMove
PictureBox2.Image = Image.FromFile(picturePath)
End Sub
Private Sub PictureBox3_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox3.MouseMove
PictureBox3.Image = Image.FromFile(picturePath)
End Sub
Private Sub PictureBox4_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox4.MouseMove
PictureBox4.Image = Image.FromFile(picturePath)
End Sub
Private Sub PictureBox5_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox5.MouseMove
PictureBox5.Image = Image.FromFile(picturePath)
End Sub
Private Sub PictureBox6_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox6.MouseMove
PictureBox6.Image = Image.FromFile(picturePath)
End Sub
Private Sub PictureBox7_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox7.MouseMove
PictureBox7.Image = Image.FromFile(picturePath)
End Sub
This works fine, however, I am looking to condense my code. Surely there is a way of making this into just 1 or 2 private subs.
Note that this is just a snippet of my code.
The names of the objects are easily named PictureBox1, PictureBox2 etc.
Regards
Hugo.
Private Sub PictureBox_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove, PictureBox2.MouseMove, PictureBox3.MouseMove, PictureBox4.MouseMove, PictureBox5.MouseMove, PictureBox6.MouseMove, PictureBox7.MouseMove
DirectCast(sender, PictureBox).Image = Image.FromFile(picturePath)
End Sub
i am getting really annoyed by this piece of code for visual basic
please can you help. i have looked on YouTube and everywhere else even the vb website!!! i would really appreciate it if someone could help me out
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
MessageBox.Show("Hi!!")
Timer1.Start()
End Sub
Private Sub ProgressBar1_Click(sender As Object, e As EventArgs) Handles ProgressBar1.Click
End Sub
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
ProgressBar1.Increment(1)
If ProgressBar1.Value = 100 Then
Timer1.Stop()
MsgBox("Jeff")
End If
End Sub
Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs)
End Sub
Private Function GetNumericUpDown1(v As Integer) As Boolean
End Function
Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
If ( : ( ) Then
MessageBox.Show("Well Done!")
End If
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
MessageBox.Show("!!Stopped!!")
Timer2.Stop()
End Sub
Private Sub Timer2_Tick(sender As Object, e As EventArgs) Handles Timer2.Tick
ProgressBar2.Increment(0.6)
If ProgressBar2.Value = 100 Then
Timer2.Stop()
MsgBox("Jeff")
End If
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
MessageBox.Show("!!Started!!")
Timer2.Start()
End Sub
Private Sub SplitContainer1_Panel1_Paint(sender As Object, e As PaintEventArgs) Handles SplitContainer1.Panel1.Paint
End Sub
Private Sub NotifyIcon1_MouseDoubleClick(sender As Object, e As MouseEventArgs)
End Sub
Private Sub TreeView1_AfterSelect(sender As Object, e As TreeViewEventArgs)
End Sub
Private Sub Timer3_Tick(sender As Object, e As EventArgs) Handles Timer3.Tick
ProgressBar3.Increment(1)
If ProgressBar3.Value = 100 Then
Timer3.Stop()
End If
End Sub
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
Timer3.Start()
End Sub
Private Sub ProgressBar3_Click(sender As Object, e As EventArgs) Handles ProgressBar3.Click
End Sub
End Class
BTW:this is my first post so it is probably rubbish!!
I don't have enough points to comment.
First off, as others have said we can't recreate this since we have no idea what your Form looks like or what you are expecting it to do.
Secondly, you should turn on Option Strict in the Compile section of Project properties to avoid technical errors like ProgressBar2.Increment(0.6) since 0.6 isn't a valid integer.
I threw together a TabControl (which you never mentioned in the OP) with 3 tabs and the various buttons and progress bars you list in what seemed like a logical fashion to me and it ran just fine for what code you have. Clicked the button on each tab and each progress bar eventually got to 100%. I have no idea what else you were expecting.
If you remove all the empty subs and action listeners, it would be easier to detect the problem
I'm very frustrated trying to get my code to work.
I'm trying to have a selected item in a listbox removed also in the textbox.
Getting ready to remove text;
Removed the text;
But it's still in the textbox.
Here is my code
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
ListBox1.Items.Add(TextBox1.Text)
TextBox2.Text += TextBox1.Text & vbNewLine
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
ListBox1.Items.Remove(ListBox1.SelectedItem)
'
'//HOW TO REMOVE THE SELECTED TEXT IN THE LISTBOX ALSO REMOVED IN THE TEXTBOX2??
'
'
End Sub
Private Sub Form1_FormClosing(sender As Object, e As FormClosingEventArgs) Handles Me.FormClosing
Dim filenames As String = "C:\log\log.txt"
My.Computer.FileSystem.WriteAllText(filenames, TextBox2.Text, False)
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim filenames As String = "C:\log\log.txt"
If My.Computer.FileSystem.FileExists(filenames) Then
TextBox2.Text = My.Computer.FileSystem.ReadAllText(filenames)
Dim items()
items = TextBox2.Lines()
For Each item In items
ListBox1.Items.Add(item)
Next
End If
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Clipboard.SetText(ListBox1.SelectedItem)
End Sub
End Class
The worst part is that every time I try to look it up online, there are no errors until I click the button that says 'Value Cannot Be Null'
It happened every single time.
Please, before you mash the -1 button, at least tell me why. I'm new to this.
This should work for you
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
TextBox1.Text = TextBox1.Text.Replace(ListBox1.Items(ListBox1.SelectedIndex), Nothing)
ListBox1.Items.RemoveAt(ListBox1.SelectedIndex)
End Sub
End Class
Looking to save combobox items to my.settings collection. I developed a webbrowser and a combobox will be my address bar. I am attempting to save a history of visited sites.
I tried the below code and it doesnt work. It errors out with "Object reference not set to an instance of an object":
Went into settings added MyItems for the name, and then select System.Collections.Specialized.StringCollection as the data type. Then onload is the below:
For Each i As String In My.Settings.MyItems
ComboBox1.Items.Add(i)
Next
FormClosing and ive tried FormClosed: For now i put it in a button event to save it for testing
My.Settings.MyItems.Clear()
For Each i As String In ComboBox1.Items
My.Settings.MyItems.Add(i)
Next
I love this site very much! So I came back to post the correct code that will correctly save and load combobox entries to my.setting! This has been tested as working!!!
Private Sub Form1_FormClosing(
sender As Object,
e As FormClosingEventArgs) Handles Me.FormClosing
My.Settings.Categories.Clear()
For Each item In ComboBox1.Items
My.Settings.Categories.Add(item.ToString)
Next
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
For Each item In My.Settings.Categories
ComboBox1.Items.Add(item)
Next
ComboBox1.SelectedIndex = 0
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
ComboBox1.Items.Add(TextBox1.Text)
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
If ComboBox1.Items.Count > 0 Then
Dim Index As Int32 = ComboBox1.SelectedIndex
ComboBox1.Items.RemoveAt(Index)
If Index - 1 <> -1 Then
ComboBox1.SelectedIndex = Index - 1
End If
End If
End Sub