Custom Cell Control in Grid Designer

[Desis Machino]

If I have correctly created a custom control, is it possible for me to relect that control as one of the Cell Types shown in the drop down list in the Grid Designer GUI?

[Administrator]

No, it's not possible. We have planned to add support for that in a future version.

What you could do right now instead is derive from GridControl and in your derived controls constructor you call CellModels.Add

Then users could manually type in the CellType. (But it will not appear in the dropdown list).

Stefan

[Desis Machino]

I have tried to do as you indicated above and created a custom control which inherits from a GridControl, however, when I try to add this custom control to my form, I get this error "Object reference not set to an instance of an object", and the object does not get added at all.

Any ideas on what I may be doing wrong?

[Administrator]

A custom cell control should be derived from a cell renderer class and cell model class. Such a control is not derived from GridControl.

Are you deriving your custom control from these two classes as discussed in the \Syncfusion\Essential Suite\Grid\Samples\In Depth\DerivedCellControlTutorial? There are lots of samples of derived cell types, do a search on CellModels.Add in the Grid\Samples folder to bring up all the different custom cells shown in the samples.

[Desis Machino]

I have correctly derived a custom CellRenderer and CellModel class, but I want a way for my developers to use this cell type without having to add this cell type model to the GridControl everytime they want to use it.

The solution which was given to be before (second response above) was to derive GridControl and add that custom CellModel in the derived control constructor.

This way my developers can simply add the derived control from the toolbox in the same way a normal GridControl is used.

[Administrator]

Sorry for the misread.

Instead of adding the new cell control in the constructor of your derived grid, override OnCellModelsChanged and add the control there.

public class MyGridControl : GridControl
{
	public MyGridControl(): base()
	{
	}

	protected override void OnCellModelsChanged(CollectionChangeEventArgs e)
	{
		base.OnCellModelsChanged(e);
		this.CellModels.Add("NewControl", new GridPushButtonCellModel(this.Model)); //just some new cell...
	}
}

[Administrator]

To avoid adding the control more than once, you can protect the Add statement with code like:

if(!this.CellModels.ContainsKey("NewControl"))
{
        this.CellModels.Add("NewControl",....
}