Suggestion for a time grid? - vb.net

Question

In VB.NET I'm looking to build a "Time" grid very similar to the Time Restriction grid of the Parental Section of Windows: http://www.thinkbroadband.com/images/guides/time-restrictions.png
It needs to toggle between 2 colors on cell-click
I've played around with One-Cell = One-Label and it kinda works but, like the Windows Time Restriction grid, I'd like to have the labels change colors if I move over the label whilst having the left button pressed (and not only on label click).
Here is what I currently have:
Private Sub ColorToggle(sender As Object, e As MouseEventArgs) Handles Label1.Click, Label2.Click, Label3.Click 'etc..
If e.Button = Windows.Forms.MouseButtons.Left Then
sender.backcolor = If(sender.backcolor = SystemColors.Control, Color.LightGreen, SystemColors.Control)
End If
End Sub
Since the sender stays the same when I hover the labels (sender = label I've originally clicked on), this code doesn't work for my purpose.
I'm looking for suggestions!
Thanks :)

Answer 1

When you click on a control and you hold the mouse button down, this control captures the following mouse events, so that you won't get events from the other lables when moving the mouse over them.
The trick is to set label.Capture = False.
Lets define colors:
Private ReadOnly selectedColor As Color = Color.Blue
Private ReadOnly unselectedColor As Color = Color.White
And Booleans storing the current state of our operations
Private isSelecting As Boolean = False
Private isUnselecting As Boolean = False
(All four as fields of the form class)
Now lets write these three event handlers:
Private Sub Label_MouseDown(sender As Object, e As EventArgs)
'This event starts selecting/unselecting
Dim label = DirectCast(sender, Label)
label.Capture = False '<=== THIS IS IMPORTANT!
If label.BackColor = selectedColor Then
isUnselecting = True
Else
isSelecting = True
End If
SelectLabel(label)
End Sub
Private Sub Label_MouseUp(sender As Object, e As EventArgs)
'This event stops selecting/unselecting
isSelecting = False
isUnselecting = False
End Sub
Private Sub Label_MouseEnter(sender As Object, e As EventArgs)
SelectLabel(DirectCast(sender, Label))
End Sub
And we need this procedure that selects or unselects the labels:
Private Sub SelectLabel(label As Label)
If isSelecting Then
label.BackColor = selectedColor
ElseIf isUnselecting Then
label.BackColor = unselectedColor
End If
End Sub
That's it!
Footnote: I have created the lables like this:
Private Sub Form_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Const w As Integer = 50, h As Integer = 50
For x = 1 To 10
For y = 1 To 10
Dim lbl As New Label() With {
.Location = New Point(x * w, y * h),
.Size = New Size(w, h),
.BorderStyle = BorderStyle.FixedSingle,
.BackColor = unselectedColor
}
AddHandler lbl.MouseDown, AddressOf Label_MouseDown
AddHandler lbl.MouseUp, AddressOf Label_MouseUp
AddHandler lbl.MouseEnter, AddressOf Label_MouseEnter
Controls.Add(lbl)
Next
Next
End Sub

Answer 2

I hope this isn't homework...
Private Sub Button8_Click(sender As Object, e As EventArgs) Handles Button8.Click
Dim i As Integer
With dgv
.ColumnCount = 0
.DataSource = Nothing
.Columns.Add("Day", "Day")
For i = 0 To 23
.Columns.Add(i, i)
.Columns(.Columns.Count - 1).Width = 30
Next
For i = 1 To 7
.Rows.Add({i})
Next
End With
End Sub
Private Sub dgv_CellClick(sender As Object, e As DataGridViewCellEventArgs) Handles dgv.CellClick
dgv.CurrentCell.Style.BackColor = Color.Blue
End Sub
Here is a drag version:
Private Sub dgv_MouseUp(sender As Object, e As MouseEventArgs) Handles dgv.MouseUp
For Each cell As DataGridViewCell In dgv.SelectedCells
If cell.Style.BackColor = Color.Blue Then
cell.Style.BackColor = Color.White
Else
cell.Style.BackColor = Color.Blue
End If
Next
dgv.ClearSelection()
End Sub