List box on multi-line textbox

[decrypt]

I am trying to create something similiar to that which is featured in Visual Studio.net. I am sure you are very familiar with the list box that appears when you type in something like "textbox1." and then it displays a list of possible endings to the line. Basically what I want to create is something that does this exact same thing, except I tell it what to say. So far, I have a program similiar to that of notepad. What I want it to do, is as I put a period in, it reads the word prior to the period, and if anything is available for the word, it displays a list box just like that in the vs.net development environment. I can go up and down the list with the arrow keys, and as I type in the word after the period, it narrows down on possible things it could be.

 

So basically, it has to act exactly like how it works in the visual studio development environment, except it runs on my program, and I define everything.

 

For example:

If I were to type in hello in the notepad I created, and then put a period on the end of it, it would display all the results that I programmed it to give:

 

hello.text

hello.blah

hello.blah2

hello.blah3

hello.listgoeson

 

I hope I have explained this well enough, and I was wondering if someone could point me in the direction of what I could use.

 

Thanks in advanced,

decrypt

[Machaira]

Here's something I whipped up to get you started. Hopefully it's useful.

WindowsApplication1.zip

Edited June 14, 2005 by PlausiblyDamp

[decrypt]

            lst.Location = New Point(TextBox1.Left + TextBox1.Width / 2, TextBox1.Top + TextBox1.Height / 2)
           lst.Visible = True

           AddHandler lst.SelectedIndexChanged, AddressOf GetSelection

           Me.Controls.Add(lst)

           lst.BringToFront()

 

at this point in the code, I'm sure it's supposed to display the listbox when I type in "Hello.", but nothing happens...

[snarfblam]

I tried the attatched code and it worked, but it was buggy.

[Machaira]

Never claimed it wasn't. ;) That's what happens when you whip something up. :D

[Machaira]

            lst.Location = New Point(TextBox1.Left + TextBox1.Width / 2, TextBox1.Top + TextBox1.Height / 2)
           lst.Visible = True

           AddHandler lst.SelectedIndexChanged, AddressOf GetSelection

           Me.Controls.Add(lst)

           lst.BringToFront()

 

at this point in the code, I'm sure it's supposed to display the listbox when I type in "Hello.", but nothing happens...

Is "Hello." the only thing you've typed? I believe the code looks for a space before it so if it's the only thing it won't pop up anything

[decrypt]

oh, ok, I see how it works now...

 

Thanks a lot for the code :)

 

edit:

 

the only thing I can't figure out is how to get the listbox to follow the text...

Edited June 16, 2005 by decrypt

[decrypt]

Private Sub txtMain_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtMain.KeyPress
       If e.KeyChar = "." Then
           Dim lst As New ListBox
           Dim index As Integer
           Dim key As String

           If txtMain.SelectionStart - 1 = -1 Then
               Exit Sub
           End If

           index = txtMain.SelectionStart - 1

           Do While txtMain.Text.Substring(index, 1) <> " "
               index -= 1
               If index = -1 Then Return
           Loop

           key = txtMain.Text.Substring(index + 1, txtMain.SelectionStart - index - 1)

           lst.Location = New Point(txtMain.SelectionStart, 200)

           'here
           If key.ToLower = "hello" Then
               lst.Items.Add("hello")
               lst.Items.Add("second")
               lst.Items.Add("what")
               lst.Visible = True
               lst.SelectedIndex = 0
           ElseIf key.ToLower = "what" Then
               lst.Items.Add("what")
               lst.Items.Add("google")
               lst.Visible = True
               lst.SelectedIndex = 0
           Else
               Exit Sub
           End If

           'here

           AddHandler lst.KeyDown, AddressOf lstKeyDown
           AddHandler lst.MouseDown, AddressOf lstMouseDown
           AddHandler txtMain.KeyDown, AddressOf txtMainKeyDown

           Me.Controls.Add(lst)
           lst.BringToFront()
           lst.ScrollAlwaysVisible = True
           lst.Select()
       End If
   End Sub
   Private Sub lstKeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs)
       If e.KeyCode = Keys.Enter Then
           If CType(sender, ListBox).SelectedIndex > -1 Then

               Dim index As Integer = txtMain.SelectionStart

               txtMain.Text = txtMain.Text.Insert(txtMain.SelectionStart, CType(sender, ListBox).SelectedItem)

               txtMain.SelectionStart = index + CType(CType(sender, ListBox).SelectedItem, String).Length

               Me.Controls.Remove(sender)

           End If
       End If
   End Sub
   Private Sub lstMouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs)
       If CType(sender, ListBox).SelectedIndex > -1 Then

           Dim index As Integer = txtMain.SelectionStart

           txtMain.Text = txtMain.Text.Insert(txtMain.SelectionStart, CType(sender, ListBox).SelectedItem)

           txtMain.SelectionStart = index + CType(CType(sender, ListBox).SelectedItem, String).Length

           Me.Controls.Remove(sender)

       End If
   End Sub
   Private Sub txtMainKeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs)
       If e.KeyCode = Keys.Space Then
       End If
   End Sub

 

Ok, I moved around your code a lot to make it more understandable for myself. Now, there is one major thing that I can't seem to work out. How could I be able to type on the main form, and at the same time, be able to move up and down on the list box with the up and down arrow keys. Also, while I'm typing, it would go down in the listbox to the letter that it starts with. So when I type in something like 'Pizza.he', it would highlight the topmost thing in the listbox that starts with 'he'.

 

I have also changed it to a richtextbox instead of a textbox

Edited June 25, 2005 by decrypt

[Machaira]

If I'm understanding you correctly you won't be able to do the first thing. Only one control can have focus at one time so you can't type in a textbox and use the arrow keys to move around in the list unless you handle the arrow keys in one of the textbox's Key events.

 

As for the second part you can do something like:

 

ListBox1.SelectedIndex = ListBox1.FindString(TextBox1.Text)

[decrypt]

thanks, a lot I got it working. I even got it to input what I type on the textbox while navigating through. Thanks a lot everybody.

 

The only thing I cannot figure out, is how to position the listbox with the current selectedindex on the richtextbox.

Edited June 27, 2005 by decrypt