Making a custom listbox - c#

If I want to make a custom listbox by inheriting from the ListBox class and overriding some functions, should I be making a User Control or a Custom Control? I've read that I should be using a user control but when I add a user control, it comes with a panel control in the designer that I can't remove whereas custom control is blank and I can drag anything to it.
And when I try to change public partial class UserControl1 : UserControl to public partial class UserControl1 : ListBox for a User Control, VS doesn't add properties like AutoScaleMode and AutoScaleDimensions.

A UserControl is a container control. It doesn't "come with" a Panel - it is a sort of "panel" (but not a Panel - that's just an empty ContainerControl). So you can position them. A custom control is just derived from Control and you create and position things purely in code, though usually you wouldn't have subcontrols in a simple Control.
As for inheriting from ListBox, you have to add those properties yourself, unless I'm misunderstanding completely.
By the way, if you just need to draw custom elements in the ListBox, but not change functionality, consider owner-drawing the ListBox instead. There are many examples on the Internet.

Related

Drawing control from Control.Controls in C# Windows Forms

Good day. How to add user control to another user control without using the Control.Controls property? For example, draw a Button on the MyControl : Control object, that the events of button be available? I want to create MyControl that contains another controls, but the Control.Controls collection must be empty, as in all standard WinForms controls.
When you add control to MyControl, it will be something like
this.Controls.Add(control);
otherwise control is not displayed. So you can not avoid this.
What is the problem to have controls in Controls ? Standard controls are not composed from other controls (there are exceptions though: DataGridView in edit mode and PropertyGrid, maybe more).
However you can use dirty tricks, like:
add control to a parent, wiring up necessary events to MyControl;
mimic control (to example, Label, by outputting text in OnPaint event).
Wouldn't it be much easier to fight with that what has problem with Controls (if there is actually any problem) ?

Hiding properties and methods of usercontrol class in C#

I have a UserControl . Problem is when i dropped it into another form. It exposes all the properties and methods of user control which is a issue in my case.
I want to expose only that properties and methods which is in my CustomControl class not in UserControl class.
That's how it works.
When I do the same in Visual Studio, the properies of CustomControl in the suggestions drop down is bold and properties of UserControl is normal text so it is easy to differentiate.

Editing Custom Controls or Panels in the Designer environment

I have created a custom control that inherits System.Windows.Forms.Panel, and adds a few extra properties. I then intend to create child classes that inherit this custom-panel class, and add content to them.
The custom-panel class will be passed to a "Wizard" framework (with back/next buttons) as the content for the various steps. I intend to make extensive use of this, creating 40-50 different pages for Wizards to handle various things in my project.
Question: Is there a way to view just the panel in the Designer, and modify its layout and design from there? I could code everything the hard way, but I really don't want to.
I did some searching and found this article, but that discusses creating a custom control and adding it to a library. I don't need to do this, I just want to view/edit the control in Designer directly, without adding it to a Form.
Obvious Answer to the rescue again.
Create a custom control, add the layout/split panel as desired, and change it's property to DockStyle.Fill.
This makes your custom control "behave" like the layout control, as long as you add all other controls to the layout control.
add first this name space
using System.ComponentModel.Design;
Apply the System.ComponentModel.DesignerAttribute attribute to the control as follows:
[Designer("System.Windows.Forms.Design.ParentControlDesigner, System.Design", typeof(IDesigner))]
public class UserControl1 : System.Windows.Forms.UserControl
{
...
}
now you can edit your custom user control in designer environment

C# visually subclass datagridview control VS2005

Maybe its something stupid, but I'm having a problem with a subclass of a DataGridView Control in VS2005 C#. I know I can subclass from almost anything by doing
public class MyDataGridView : DataGridView
{}
no problem, and I put in some things / elements I want applicable globally. Now, I take this gridview and put into a custom user control that will contain other controls too. So I have something like created by the visual designer. I grab some buttons, label, and my derived "MyDataGridView" on it.
public partial class MyCompoundDGVPlus : UserControl
So, now, I can visually draw, move, change all sorts of settings as needed, no problem.
Now, I want this "MyCompoundDGVPlus" class as the basis for other classes, of which I will manipulate settings specific, but want all to have the same look / feel, and otherwise similar flow, hence the derivations.
I've even set the "modifiers" setting to public, so I SHOULD be able to modify any of the properties of the controls at any derived level. So, now, I create a new subclass of "MyFirstDetailedDGVPlus" derived from "MyCompoundDGVPlus". Ok visually, all the label, button, datagridview appear. However, now I want to specifically define the columns of the datagridview here in this class visually, but its locked. However, the LABEL on the form, I CAN get all the property settings....
What am I missing.
Maybe you should take a look at this post as it seems to do what you are looking for :
DataGridView locked on a inherited UserControl

Using C# WinForms Designer on Panel instead of Form Again?

I have the same question, but the answer to use a UserControl will not do. I also need to create a control container that I can add other controls to at design time so I can add it to yet another container (Splitter Panel) which is not avaialable to me at design time (plugin architecture). When I make a User Control, it is missing the design time support and all I get are icons when I drop controls onto this surface.
Do I need to add all the design time support myself, or is there something I am missing that has this for me?
You will have to use either a Form or UserControl to accomplish any forms design within the designer.
I have often created controls that I need to manipulate en masse. Start with a UserControl, then add a panel that fills the UserControl. This is your base panel that you will fill with all of your controls. I then save as a duplicate control and simply remove the UserControl and leave the panel as the public UI control which is then instanced. If I am making changes, I can go back to the original UserControl, make changes, add code, etc - rinse and repeat.

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