Vb.net add panel to top of user control năm 2024

Answered Closed

Hi,

In dropped two Panels in Window1, one is docked top and the other is docked at the bottom, I added a new User Control and put a Toolbar docked on top. When I dropped the User Control in Window1 using the Designer and set Dock=Fill, it works OK. However, when I removed the User Control from the Designer and created an instance of the User Control at runtime, the Toolbar is covered by Panel. The code is:

UserControl1 uc = new UserControl1(); uc.Dock = DockStyle.Fill; this.Controls.Add(uc);

Thanks,

Cris

• Cris asked May 26, 2016 - 5:22 am
• last edited Aug 31, 2019 - 8:30 pm

Best Answer

Hi Cris,

Docking is applied using the z-order of the controls so Fill will fill whatever space is left available by other docked controls. When you use Controls.Add() the new control is rendered first since the z-order is from further away coming toward the viewer. For the Fill to use the remaining space use uc.BringToFront() after adding it to the parent.

You can test the order of docking and how the different sides overlap in the designer using right-click -> SendToBack/BringToFront.

Best,

Luca

• Luca (ITG) answered May 26, 2016 - 4:24 pm

Hi Luca,

I have to add uc.BringToFront() to make it worked. Another option is to put another panel, dock it to Fill and make it as a container of the UserControl.

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Extend an existing control

• Article
• 08/04/2023

In this article

If you want to add more features to an existing control, you can create a control that inherits from an existing control. The new control contains all of the capabilities and visual aspect of the base control, but gives you opportunity to extend it. For example, if you created a control that inherits Button, your new control would look and act exactly like a button. You could create new methods and properties to customize the behavior of the control. Some controls allow you to override the OnPaint method to change the way the control looks.

Important

The Desktop Guide documentation for .NET 7 and .NET 6 is under construction.

Add a custom control to a project

After creating a new project, use the Visual Studio templates to create a user control. The following steps demonstrate how to add a user control to your project:

1. In Visual Studio, find the Project Explorer pane. Right-click on the project and choose Add > Class.
2. In the Name box, type a name for your user control. Visual Studio provides a default and unique name that you may use. Next, press Add.

After the user control is created, Visual Studio opens the code-editor for the control. The next step is to turn this custom control into a button and extend it.

Change the custom control to a button

In this section, you learn how to change a custom control into a button that counts and displays the number of times it's clicked.

After named

Public Class CustomControl2Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class

0, the control designer should be opened. If it's not, double-click on the control in the Solution Explorer. Follow these steps to convert the custom control into a control that inherits from

Public Class CustomControl2Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class

1 and extends it:

1. With the control designer opened, press F7 or right-click on the designer window and select View Code.
2. In the code-editor, you should see a class definition: namespace CustomControlProject

   { public partial class CustomControl2 : Control { public CustomControl2() { InitializeComponent(); } protected override void OnPaint(PaintEventArgs pe) { base.OnPaint(pe); } } }

   Public Class CustomControl2 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class
3. First, add a class-scoped variable named Public Class CustomControl2 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class
4. private int _counter = 0; Private _counter As Integer = 0
5. Override the Public Class CustomControl2 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class

   3 method. This method draws the control. The control should draw a string on top of the button, so you must call the base class'

   Public Class CustomControl2 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class

   3 method first, then draw a string.

   protected override void OnPaint(PaintEventArgs pe)

   { // Draw the control base.OnPaint(pe); // Paint our string on top of it pe.Graphics.DrawString($"Clicked {_counter} times", Font, Brushes.Purple, new PointF(3, 3)); }

   Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) ' Draw the control MyBase.OnPaint(e) ' Paint our string on top of it e.Graphics.DrawString($"Clicked {_counter} times", Font, Brushes.Purple, New PointF(3, 3)) End Sub
6. Lastly, override the Public Class CustomControl2 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class

   5 method. This method is called every time the control is pressed. The code is going to increase the counter, and then call the

   Public Class CustomControl2 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) MyBase.OnPaint(e) 'Add your custom paint code here End Sub End Class

   6 method, which forces the control to redraw itself.

   protected override void OnClick(EventArgs e)

   { // Increase the counter and redraw the control _counter++; Invalidate(); // Call the base method to invoke the Click event base.OnClick(e); }

   Protected Overrides Sub OnClick(e As EventArgs) ' Increase the counter and redraw the control _counter += 1 Invalidate() ' Call the base method to invoke the Click event MyBase.OnClick(e) End Sub

   The final code should look like the following snippet:

   public partial class CustomControl1 : Button

   { private int _counter = 0; public CustomControl1() { InitializeComponent(); } protected override void OnPaint(PaintEventArgs pe) { // Draw the control base.OnPaint(pe); // Paint our string on top of it pe.Graphics.DrawString($"Clicked {_counter} times", Font, Brushes.Purple, new PointF(3, 3)); } protected override void OnClick(EventArgs e) { // Increase the counter and redraw the control _counter++; Invalidate(); // Call the base method to invoke the Click event base.OnClick(e); } }

   Public Class CustomControl1 Private _counter As Integer = 0 Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) ' Draw the control MyBase.OnPaint(e) ' Paint our string on top of it e.Graphics.DrawString($"Clicked {_counter} times", Font, Brushes.Purple, New PointF(3, 3)) End Sub Protected Overrides Sub OnClick(e As EventArgs) ' Increase the counter and redraw the control _counter += 1 Invalidate() ' Call the base method to invoke the Click event MyBase.OnClick(e) End Sub End Class

Now that the control is created, compile the project to populate the Toolbox window with the new control. Open a form designer and drag the control to the form. When you run the project and click the button, you'll see that it counts the clicks and paints the text on top of the button.

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How do I add user control to panel in VB net?

Add a user control to a project In Visual Studio, find the Project Explorer pane. Right-click on the project and choose Add > User Control (Windows Forms). In the Name box, type a name for your user control.

What is the difference between user control and panel?

According to MSDN the Panel class is "Used to group collections of controls", while the User Control "Provides an empty control that can be used to create other controls".

What is the difference between panel and GroupBox?

Panel Versus GroupBoxThe Panel control is similar to the GroupBox control; however, only the Panel control can have scroll bars, and only the GroupBox control displays a caption.

How do you add control to the panel in Windows Forms?

To create a group of controlsDrag a Panel control from the Windows Forms tab of the Toolbox onto a form. Add other controls to the panel, drawing each inside the panel.