ColorDialog Box in VB.NET

A ColorDialog control is used to select a color from available colors and also define custom colors. This article demonstrates how to use a ColorDialog in Windows Forms and VB.NET.
  • 2721
Download Files:
 

Color Dialog

A ColorDialog control is used to select a color from available colors and also define custom colors. A typical Color Dialog looks like Figure 1 where you can see there is a list of basic solid colors and there is an option to create custom colors.

 

ColorDialogImg1.jpg
Figure 1

Creating a ColorDialog

We can create a ColorDialog control using a Forms designer at design-time or using the ColorDialog class in code at run-time (also known as dynamically). Unlike other Windows Forms controls, a ColorDialog does not have and not need visual properties like others. The only purpose of ColorDialog to display available colors, create custom colors and select a color from these colors. Once a color is selected, we need that color in our code so we can apply it on other controls.

Again, you can create a ColorDialog at design-time but It is easier to create a ColorDialog at run-time.

Design-time

To create a ColorDialog control at design-time, you simply drag and drop a ColorDialog control from Toolbox to a Form in Visual Studio. After you drag and drop a ColorDialog on a Form, the ColorDialog looks like Figure 2.

 

ColorDialogImg2.jpg
Figure 2

Adding a ColorDialog to a Form adds following two lines of code.

 

Friend WithEvents ColorDialog1 As System.Windows.Forms.ColorDialog

Me.ColorDialog1 = New System.Windows.Forms.ColorDialog()

Run-time

Creating a ColorDialog control at run-time is merely a work of creating an instance of ColorDialog class, set its properties and add ColorDialog class to the Form controls.

First step to create a dynamic ColorDialog is to create an instance of ColorDialog class. The following code snippet creates a ColorDialog control object.

Dim colorDlg As New ColorDialog()

 

ShowDialog method of ColorDialog displays the ColorDialog. The following code snippet sets background color, foreground color, Text, Name, and Font properties of a ColorDialog.

colorDlg.ShowDialog()

 

Once the ShowDialog method is called, you can pick colors on the dialog.

 

Setting ColorDialog Properties

After you place a ColorDialog control on a Form, the next step is to set properties.

The easiest way to set properties is from the Properties Window. You can open Properties window by pressing F4 or right click on a control and select Properties menu item. The Properties window looks like Figure 3.

 

ColorDialogImg3.jpg
Figure 3

AllowFullOpen

If you look at Figure 1, you will see a button called Define Custom Colors on the ColorDialog. Clicking on this button opens the custom color editor area where you can define colors by setting RGB color values (between 0 to 255) and can also select a color from the color area as you can see in Figure 4.

 

ColorDialogImg4.jpg
Figure 4

AllowFullOpen property makes sure that Define Custom Color option is enabled on a ColorDialog. If you wish to disable this option, you can set AllowFullOpen property to false and your ColorDialog will look like Figure 5.

 

ColorDialogImg5.jpg
Figure 5

 

 

The following code snippet sets the AllowFullOpen property to false.

colorDlg.AllowFullOpen = False

Color, AnyColor, and SolidColorOnly

Color property is used to get and set the color selected by the user in a ColorDialog.

AnyColor is used to get and set whether a ColorDialog displays all available colors in the set of basic colors.

SolidColorOnly is used to get and set whether a ColorDialog restricts users to selecting solid colors only.

The following code snippet sets these properties.

colorDlg.Color = Color.Red

colorDlg.SolidColorOnly = False

Using ColorDialog in Applications

Now let's create an application that will use a ColorDialog to set colors of bunch of controls. The Windows Forms application looks like Figure 6.

 

ColorDialogImg6.jpg
Figure 6

In Figure 6, we have a few Windows Forms controls and clicking on Foreground Color and Background Color buttons will let user select a color and set that color as foreground and background colors of the controls. After selecting foreground and background colors, the Form looks like Figure 7.

 

ColorDialogImg7.jpg
Figure 7

The following code snippet is the code for Foreground Color and Background Color buttons click event handlers.

Public Class Form1

 

    Private Sub ForegroundButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ForegroundButton.Click

        Dim colorDlg As New ColorDialog()

        colorDlg.AllowFullOpen = False

        colorDlg.ShowHelp = True

        colorDlg.Color = Color.Red

        colorDlg.SolidColorOnly = False

 

        If (colorDlg.ShowDialog() = Windows.Forms.DialogResult.OK) Then

            TextBox1.ForeColor = colorDlg.Color

            ListBox1.ForeColor = colorDlg.Color

            Button3.ForeColor = colorDlg.Color

        End If

 

    End Sub

 

    Private Sub BackgroundButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BackgroundButton.Click

        Dim colorDlg As New ColorDialog()

        If (colorDlg.ShowDialog() = Windows.Forms.DialogResult.OK) Then

            TextBox1.BackColor = colorDlg.Color

            ListBox1.BackColor = colorDlg.Color

            Button3.BackColor = colorDlg.Color

        End If

 

    End Sub

 

    Private Sub AddButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AddButton.Click

        ListBox1.Items.Add(TextBox1.Text)

    End Sub

End Class


Summary 

A ColorDialog control allows users to launch Windows Color Dialog and let them select a solid color or create a custom color from available colors. In this article, we discussed how to use a Windows Color Dialog and set its properties in a Windows Forms application.

Categories

More Articles

© 2013 dotNetheaven. All rights reserved.