Listboxs with multicolored items

Listboxs with multicolored items

• Alexandrea

  A single column Listview in Detail view would be the simpliest

  
  

• Tammt

  here is a sample to draw custom colors on each item in a standard listbox...you of course will have to keep track of you priority items to draw those indexes a specific color...

  Dim MyBrush() As System.Drawing.Brush = New System.Drawing.Brush() {Brushes.Blue, Brushes.Black, Brushes.DarkGreen, Brushes.Coral, Brushes.DarkGray, Brushes.DarkMagenta, _

  Brushes.Brown, Brushes.Aqua, Brushes.Gold, Brushes.Orange, Brushes.RoyalBlue}

  Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

  For x As Integer = 1 To 10

  Me.ListBox1.Items.Add("Item" & x)

  Next

  End Sub

  Private Sub ListBox1_DrawItem(ByVal sender As Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles ListBox1.DrawItem

  e.Graphics.DrawString(Me.ListBox1.Items(e.Index).ToString, Me.Font, MyBrush(e.Index), e.Bounds.X, e.Bounds.Y)

  End Sub

  
  
  

• Dave Waterworth

  Set the draw mode of the listbox to ownerdraw
  
  

• MtEvans

  If I copy this sample to my project It doesn't work. Items haven't any colors. What I have to do else

  Thank You.

  
  

• cedubose

  Waltari wrote:

  I guess I'm still missing something here. How is the data added to the listbox with this method

  With the Add method, as usual. I'll flesh out the example I posted above and that might make it clearer.

  First, we have a simple class, PriorityListBoxItem that hold the description and priority. This class also has an Enum for the Priority values. Note that the New constructor allows you to pass in the values for the properties. In a more 'real world' application, you might populate here from a query, datarow from a query, an XmlElement, or any other source of data.

  Public Class PriorityListBoxItem

  Public Enum PriorityValue
  LowPriority
  HighPriority
  End Enum

  Private _description As String
  Private _priority As PriorityValue

  Public Sub New(ByVal itemDescription As String, ByVal itemPriority As PriorityValue)
  Description = itemDescription
  Priority = itemPriority
  End Sub

  Public Property Description() As String
  Get
  Return _description
  End Get
  Set(ByVal value As String)
  _description = value
  End Set
  End Property

  Public Property Priority() As PriorityValue
  Get
  Return _priority
  End Get
  Set(ByVal value As PriorityValue)
  _priority = value
  End Set
  End Property

  End Class
  

  Next, in the form's Load event, we populate the listbox. In this simple example I do a loop that sets the priority High for even values and Low for odd values. In the real world, this would be done from your data source rather than a hard code. A new instance of the PriorityListBoxItem class is added to the listbox on each iteration of the loop. Remember that in .NET you're not limited to only strings in a listbox, you can store objects of any type. The only thing that you have to be aware of is your memory and performance may be impacted in some cases.

  Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
  For x As Integer = 1 To 10
  If x Mod 2 = 0 Then
  ListBox1.Items.Add(New PriorityListBoxItem("Item" & x, _
  PriorityListBoxItem.PriorityValue.HighPriority))
  Else
  ListBox1.Items.Add(New PriorityListBoxItem("Item" & x, _
  PriorityListBoxItem.PriorityValue.LowPriority))
  End If
  Next
  End Sub

  Finally, you would have the routine I posted earlier that used the DrawItem event to set the display string and it's color.

  If you wanted to do this object in a ListBox trick without the owner draw, then you would need to override the ToString function of the class since otherwise you would get the default object moniker that .NET object base class provides for this method. So, in my example, you would add the following routine to the class to return the Description property instead of the default string.

  Public Overrides Function ToString() As String
  Return Description
  End Function

  
  
  

• rod_r

  OK.Thank you very much, DMan1.
  

• Michael Schreyer

  Thanks everyone. The code appears to be working perfectly.
  

• Hamann Heinz

  I guess I'm still missing something here. How is the data added to the listbox with this method
  

• JohnSLG

  It seems you are one step ahead of me, Frank......I was just about to say that. I'm working on exactly that sort of thing at the moment.

  So I will add, you can also draw lines, circles and images as appropriate for the entry (e.g. a nice red flag...). Here's a quick screenshot of what I'm working on at present...

  http://www.playinthesoup.com/soup/misc/ownerdrawtreelist.png

  
  
  

• dgaynes

  DMan1 wrote:

  here is a sample to draw custom colors on each item in a standard listbox...you of course will have to keep track of you priority items to draw those indexes a specific color... Dim MyBrush() As System.Drawing.Brush = New System.Drawing.Brush() {Brushes.Blue, Brushes.Black, Brushes.DarkGreen, Brushes.Coral, Brushes.DarkGray, Brushes.DarkMagenta, _ Brushes.Brown, Brushes.Aqua, Brushes.Gold, Brushes.Orange, Brushes.RoyalBlue} Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load For x As Integer = 1 To 10 Me.ListBox1.Items.Add("Item" & x) Next End Sub Private Sub ListBox1_DrawItem(ByVal sender As Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles ListBox1.DrawItem e.Graphics.DrawString(Me.ListBox1.Items(e.Index).ToString, Me.Font, MyBrush(e.Index), e.Bounds.X, e.Bounds.Y) End Sub

  If I copy this sample to my project It doesn't work. Items haven't any colors. What I have to do else

  Thank You

  
  

• Kamen

  You'll have to owner draw a standard listbox. Here's a link that describes how to do it in C# but if you Google around for it you might find a version in VB.

  Other alternatives would be to use a 3rd party list box that has this feature or use Treeview or Listview controls if either of them will work for the look and feel you want.

  
  
  

• Mark Benningfield

  I've tried the owner draw option, but when I change the color in the draw event the entire list gets rewritten as the new color.
  

• Matt A

  DMan1 wrote:

  here is a sample to draw custom colors on each item in a standard listbox...you of course will have to keep track of you priority items to draw those indexes a specific color...

  I'm still being amazed at how much easier some things are to do under VB.NET than they were in VB6. That's what's great about these forums, you can learn something new just about every day.

  To add to your example, the Listbox items are objects, not strings, so you could put the object as an item in the listbox and use this object to determine the correct brush and text in the DrawItem routine, something like this:

  Private Sub ListBox1_DrawItem(ByVal sender As Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles ListBox1.DrawItem
      Dim TextBrush As System.Drawing.Brush
      Dim ListItem As PriorityListBoxItem = TryCast(ListBox1.Items(e.Index), PriorityListBoxItem)
      Select Case ListItem.Priority
          Case PriorityListBoxItem.PriorityValue.HighPriority
              TextBrush = Brushes.Red
          Case PriorityListBoxItem.PriorityValue.LowPriority
              TextBrush = Brushes.DarkGoldenrod
          Case Else
              TextBrush = Brushes.Black
      End Select
      e.Graphics.DrawString(ListItem.Description, Me.Font, TextBrush, e.Bounds.X, e.Bounds.Y)
  End Sub

  
  
  
• Listboxs with multicolored items