views:

1861

answers:

3

I have a UserControl with some predefined controls (groupbox,button,datagridview) on it, these controls are marked as protected and the components variable is also marked as protected.

I then want to inherit from this base UserControl to another UserControl, however the DataGridView is always locked in the designer.

I suspect it may have something to do with the DataGridView implementing ISupportInitilize.

public class BaseGridDetail : UserControl

Has a DataGridView control (et al) defined.


public class InheritedDetail : BaseGridDetail

The DataGridView control is locked


Does anyone have any ideas how to make this control available in the designer after inheritenace?

A: 

I left an answer but re-read your question and decided to delete it.

What is it about the DataGridView that you're trying to modify in the inherited control? It's columns? I've been able to do this by setting up a protected method in my base UserControl and passing the grid's column collection into it, like this:

// in base UserControl
public BaseGridDetail()
{
    InitializeComponent();

    InitGridColumns(dataGridView1.Columns);
}

protected virtual void InitGridColumns(DataGridViewColumnCollection columns)
{
    columns.Clear();
}

Now your derived control can simply override that method, like so:

// in InheritedDetail
protected override void InitGridColumns(DataGridViewColumnCollection columns)
{
    base.InitGridColumns(columns);
    // add my own custom columns
}
Matt Hamilton
In the designer all the controls can have any of their properties changed, except the DataGridView. It is locked down from the designer perspective completly.
benPearce
Yeah - having read Rob's answer to your question, I remembered why I had to go down the "InitGridColumns" path in my own application. Visual inheritence simply doesn't work with DataGridView.
Matt Hamilton
+4  A: 

By the looks of it, DataListView (and some other controls) do not support visual inheritance. There's a connect issue logged here which doesn't look hopeful.

There have been similar issues logged with other form controls, e.g. flowlayoutpanel.

I'm unable to find a way to force visual inheritance.

Here's the official answer on connect: "For this particular release, the DataGridView was not designed to be used in visual intheritance. We will keep your suggestion in mind when we plan our future release" That is of 26/05/2006.

Update: found this blog post which may have the answer

Edit: I was unable to verify the blog post's claims. Looks like might be the latest on this issue

It looks like you can still manipulate the DataListView at runtime though, so you might be able to set visual properties (and other settings). It's not a great compromise.

RobS
+1  A: 

[1] create Your Custom UserControl

[2] make your custom userControl use the below Inherited DataGridView:

[Designer(typeof System.Windows.Forms.Design.ControlDesigner))]
public class InheritedDataGridView : DataGridView { }

[3] Inherit from your Custom UserControl , And viola !!

[4] Ohh dont forget to add "System.Design" dll

Enjoy.

_Avishay_
I've been looking for a good workaround. This worked nicely!
Pedro