Simulate a traffic light with three small square text boxes placed vertically on
ID: 3544950 • Letter: S
Question
Simulate a traffic light with three small square text boxes placed vertically on a form. Initially, the bottom text box is solid green and the other text boxes are dark gray. When the Tab key is pressed, the middle text box turns yellow and the bottom text box turns dark gray. The next time Tab is pressed, the top text box turns red and the middle text box turns dark gray. Subsequent pressing of the Tab key cycles through the three colors. Hint: First place the bottom text box on the form, then the middle text box, and finally the top text box.
Explanation / Answer
Private Sub TextBox1_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox1.GotFocus
TextBox1.BackColor = Color.Green
TextBox3.BackColor = Color.DarkGray
End Sub
Private Sub TextBox2_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox2.GotFocus
TextBox2.BackColor = Color.Yellow
TextBox1.BackColor = Color.DarkGray
End Sub
Private Sub TextBox3_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox3.GotFocus
TextBox3.BackColor = Color.Red
TextBox2.BackColor = Color.DarkGray
End Sub