How to enable design support in a custom control? - c#

I'll try to explain what I'm after. I don't know the technical term for it, so here goes:
Example 1:
If I place a ListView on a Form and add some columns I am able, in Design-Time, to click-and-drag the columns to resize them.
Example 2:
Now, I place a ListView in a UserControl and name it "MyCustomListView" (and perhaps add some method to enhance it somehow).
If I now place the "MyCustomListView" on a Form I am unable to click-and-drag the column headers to resize them in Design-Time.
Is there any way to easily make that happen? Some form of "pass the click-and-drag event to the underlying control and let that control do its magic". Im not really looking to recode, just pass on the mouseclick (or whatever it is) and let the, in this case, ListView react as it did in the first example above.

The Windows Forms designer has dedicated designer classes for most controls. The designer for a ListView is System.Windows.Forms.Design.ListViewDesigner, an internal class in the System.Design.dll assembly. This class gives you the ability to drag the column headers.
A UserControl uses the System.Windows.Forms.Design.ControlDesigner designer class. It doesn't do anything special, just puts a rectangle around the control with drag handles. You can see where this is heading: after you put your user control on a form, it is ControlDesigner that is used to design the class, ListViewDesigner is not in the picture. You thus lose the ability to drag the column headers. Also note that ControlDesigner doesn't give access to the controls inside the UC.
That's fixable however by creating your own designer. Start with Projects + Add Reference, select System.Design. You'll need to add a public property to the UC to expose the list view and apply the [DesignerSerializationVisibility] attribute to allow changed properties to be saved. And apply the [Designer] attribute to the UC class to replace the default designer. It all should resemble this (using the default names and a ListView that displays "employees"):
using System;
using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.Design; // Note: add reference required: System.Design.dll
namespace WindowsFormsApplication1 {
[Designer(typeof(MyDesigner))] // Note: custom designer
public partial class UserControl1 : UserControl {
public UserControl1() {
InitializeComponent();
}
// Note: property added
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public ListView Employees { get { return listView1; } }
}
// Note: custom designer class added
class MyDesigner : ControlDesigner {
public override void Initialize(IComponent comp) {
base.Initialize(comp);
var uc = (UserControl1)comp;
EnableDesignMode(uc.Employees, "Employees");
}
}
}
The list view in the user control can now be clicked and designed as normal.

Related

How to design a TabPage without TabControl?

I am trying to design some "standalone" tab-pages and later on, I want to add them dynamically to a tab-control in my main form. Visual Studio won't let me open the class extended with TabPage in the designer. Some idea?
using System;
using System.Windows.Forms;
namespace Test.View.Panels {
public class MainStatusTabPage : TabPage {
public MainStatusTabPage() {
}
}
}
When I right-click the class in the Solution Explorer and selecting "View Designer", I get the following message (the Designer doesn't show up):
To add components to your class, drag them from the Toolbox and use
the Properties window to set their properties. To create methods and
events for your class, switch to code view.
When I right-click the class in the Solution Explorer and selecting "View Designer", I get the following message (the Designer doesn't show up):
To add components to your class, drag them from the Toolbox and use the Properties window to set their properties. To create methods and events for your class, switch to code view.
This is normal behavior as a TabPage is just a container that holds other controls, nothing more. As #PanagiotisKanavos mentioned above:
A Tab Page is a container, not the actual content of the tab. In all examples that use complex content you'll see that the content is a custom component, eg a User control, that's added into the tab
With this in mind, you can just create a UserControl with all the other controls you would need and then add this new instance (UserControl) to the TabPage itself.

Visual Studio Form Designer Showing List of Controls

I know that getting the Form Designer to work is a ticklish business. Generics, x64, subtle problems with the project's XML... But perhaps someone can offer advice about my current problem, which is that a component I created that inherits from TabPage, when I try to view it in the designer shows up as a list of its controls, like this:
Thanks in advance.
You cannot make a TabPage as root of the designer, while you can do the same for a Panel or other container controls. The limitation is because, TabPage can only be hosted in TabControl, not even in the overlay control of the designer:
TabPage cannot be added to a
'System.Windows.Forms.Design.DesignerFrame+OverlayControl'. TabPages
can only be added to TabControls.
A control can be shown as root of the designer when the base class of the control has designer of type of DocumentDesigner. Form and UserControl are such controls which means when you create a new Form1:Form or new UserControl1:UserControl, since the base class derived from a designable control, then the class can be edited in the designer as root.
I believe you can handle your requirement by using UserControl, but for learning purpose (or as a workaround) if you want to make a control deriving from Panel designable, you can copy the following code in a code file:
public class MyControl: MyDesignableControl
{
}
[Designer(typeof(DocumentDesigner), typeof(IRootDesigner))]
public class MyDesignableControl : Panel
{
}
Then save it and then double click on it and you can see you can design it like a root control.
Then after you done with the design, change the Panel to TabPage.
Remarks on
DocumentDesigner
This designer is a root designer, meaning that it provides the
root-level design mode view for the associated document when it is
viewed in design mode.
You can associate a designer with a type using a
DesignerAttribute.
For an overview of customizing design time behavior, see Extending
Design-Time
Support.

Design a child control of a derived Control [duplicate]

I'll try to explain what I'm after. I don't know the technical term for it, so here goes:
Example 1:
If I place a ListView on a Form and add some columns I am able, in Design-Time, to click-and-drag the columns to resize them.
Example 2:
Now, I place a ListView in a UserControl and name it "MyCustomListView" (and perhaps add some method to enhance it somehow).
If I now place the "MyCustomListView" on a Form I am unable to click-and-drag the column headers to resize them in Design-Time.
Is there any way to easily make that happen? Some form of "pass the click-and-drag event to the underlying control and let that control do its magic". Im not really looking to recode, just pass on the mouseclick (or whatever it is) and let the, in this case, ListView react as it did in the first example above.
The Windows Forms designer has dedicated designer classes for most controls. The designer for a ListView is System.Windows.Forms.Design.ListViewDesigner, an internal class in the System.Design.dll assembly. This class gives you the ability to drag the column headers.
A UserControl uses the System.Windows.Forms.Design.ControlDesigner designer class. It doesn't do anything special, just puts a rectangle around the control with drag handles. You can see where this is heading: after you put your user control on a form, it is ControlDesigner that is used to design the class, ListViewDesigner is not in the picture. You thus lose the ability to drag the column headers. Also note that ControlDesigner doesn't give access to the controls inside the UC.
That's fixable however by creating your own designer. Start with Projects + Add Reference, select System.Design. You'll need to add a public property to the UC to expose the list view and apply the [DesignerSerializationVisibility] attribute to allow changed properties to be saved. And apply the [Designer] attribute to the UC class to replace the default designer. It all should resemble this (using the default names and a ListView that displays "employees"):
using System;
using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.Design; // Note: add reference required: System.Design.dll
namespace WindowsFormsApplication1 {
[Designer(typeof(MyDesigner))] // Note: custom designer
public partial class UserControl1 : UserControl {
public UserControl1() {
InitializeComponent();
}
// Note: property added
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public ListView Employees { get { return listView1; } }
}
// Note: custom designer class added
class MyDesigner : ControlDesigner {
public override void Initialize(IComponent comp) {
base.Initialize(comp);
var uc = (UserControl1)comp;
EnableDesignMode(uc.Employees, "Employees");
}
}
}
The list view in the user control can now be clicked and designed as normal.

Showing public fields of a UserControl in designer

I am trying to add some fields to a custom UserControl that I am making. I have some fields that I like them to be visible in the Properties window of Visual Studio. I tried to use the flags below but I dont see the field in the designer, even after a compile.
How should I do this correctly?
public partial class TosChartControl: UserControl
{
#region PUBLIC FIELDS
[Browsable(true)] //Added this but still does not show up
[Category("Data")]
[DefaultValue(0)]
[Description("ID of the Sensor Node")]
public int NodeId { get; set; }
#endregion
public TosChartControl()
{
InitializeComponent();
}
}
I did clean and rebuild the soloution and projects but I cant still see this field in Properties window. Even restarting the Visualstudio didnt help.
UPDATE: Your public properties are visible in the designer only when it's in another control in the designer. It turns out that you don't need to add this attribute, properties are visible by default in the designer. As far as I understand, when it's in another component's design view, an instance of the user control is created and properties can be shown. Sorry for misleading you in the beginning, I thought it was necessary to add it.
Try this attribute:
[Browsable(true)]
http://msdn.microsoft.com/en-us/library/system.componentmodel.browsableattribute.aspx
To elaborate on henginy's updated answer:
Be sure that you are looking at an instance of the control you want to modify properties for, and not the definition of the control itself.
To clarify, when you add a property to your TosChartControl class, you won't see the property in the TosChartControl.cs [Design] tab, you will see it where you implement a TosChartControl, such as your Form1.cs [Design] tab, e.g. the containing control to which you have added your custom control.
...Assuming that your Properties window is visible, and that you have the control selected.
What to take away from this lesson:
Understanding what the properties window is actually showing you — It's contextual.
The difference between the model and the implementation of the model — e.g. Designing the custom control and designing the form that uses the custom control.

How to access inherited controls in the winforms designer

I'm making some controls which all have to share the same look and some common behavior, although they are meant for different kind of inputs. So I made a BaseClass which inherit from UserControl, and all my controls inherit from BaseClass.
However, if i add controls for BaseClass in the designer, such as a TableLayoutPanel, i can't access them when I'm designing the inherited classes. I see the TableLayoutPanel, but even though he is "protected", i can't modify it or put controls in it through the designer. I've no trouble accesing it by code, but i don't want to lose the ability to use the designer.
Right now, i simply removed all controls from BaseClass, added the layout and all the common controls in each of the inherited class, then use references to manipulate them inside BaseClass. But that doesn't satisfy me at all. Is there a way to make the designer work with inherited protected member controls ?
Environment : C#, .NET 3.5, Visual Studio 2008
EDIT to answer SLaks's suggestion. I tried setting a property, and although I'm not used to use them it doesn't seem to work. Here is the code i tried :
public partial class UserControl1 : UserControl
{
public UserControl1()
{
InitializeComponent();
}
public TableLayoutPanel TableLayoutPanel1
{
get { return tableLayoutPanel1;}
set { tableLayoutPanel1 = value;}
}
}
public partial class UserControl2 : UserControl1
{
public UserControl2()
{
InitializeComponent();
}
}
When you try to access from the inherited control with the designer to the TableLayoutPanel declared in the base control, you're using a feature in WinForms called "Visual Inheritance".
Unfortunately TableLayoutPanel doesn't support visual inheritance:
http://msdn.microsoft.com/en-us/library/ms171689%28VS.80%29.aspx
That's why the TableLayoutPanel appears blocked in the inherited controls.
Try adding this attribute to the definition of the panel (this may or may not help):
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
You have to design the base controls on their own. Changes are reflected in the designer after you successfully rebuild the controls project. If you make the members public you can edit them but the changes won't persist.
Try making a ParentControlDesigner for your control, overriding InternalControlDesigner, and returning (designerHost.GetDesigner(tableLayoutPanel) as ControlDesigner). designerHost is (IDesignerHost) component.Site.GetService(typeof(IDesignerHost)).
I vaguely remember solving a similar problem by putting the base class it its own DLL and building it first. I've had a rummage but I can't find the project. Sorry.

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