Visual Studio Designer looses / ignores data
- by Kempeth
I'm writing my own control - a datagridviewcolumn that displays integer values as texts like the comboboxcolumn can but without showing the combobox unless the cell is edited.
I'm mostly there but I have problems with the databinding. I managed to get the necessary properties to appear in the designer but every time I set the datasource and close the editor the changes are dropped.
When I assign the same datasource later in code it works like a charm, I just would prefer not having to do that...
public class DataGridViewLookupColumn : DataGridViewColumn
{
private DataGridViewLookupCell template;
private Object datasource = null;
private String displaymember = String.Empty;
private String valuemember = String.Empty;
private BindingSource bindingsource = new BindingSource();
public DataGridViewLookupColumn()
: base()
{
this.template = new DataGridViewLookupCell();
}
public override DataGridViewCell CellTemplate
{
get
{
return this.template;
}
set
{
}
}
[Category("Data")]
[
DefaultValue(null),
RefreshProperties(RefreshProperties.Repaint),
AttributeProvider(typeof(IListSource)),
DesignerSerializationVisibility(DesignerSerializationVisibility.Visible),
]
public object DataSource
{
get
{
return this.bindingsource.DataSource;
//return this.datasource;
}
set
{
this.bindingsource.DataSource = value;
this.bindingsource.EndEdit();
}
}
[Category("Data")]
[
DefaultValue(""),
TypeConverterAttribute("System.Windows.Forms.Design.DataMemberFieldConverter, System.Design"),
Editor("System.Windows.Forms.Design.DataMemberFieldEditor, System.Design", typeof(System.Drawing.Design.UITypeEditor)),
DesignerSerializationVisibility(DesignerSerializationVisibility.Visible),
]
public String DisplayMember
{
get
{
return this.displaymember;
}
set
{
this.displaymember = value;
}
}
[Category("Data")]
[
DefaultValue(""),
TypeConverterAttribute("System.Windows.Forms.Design.DataMemberFieldConverter, System.Design"),
Editor("System.Windows.Forms.Design.DataMemberFieldEditor, System.Design", typeof(System.Drawing.Design.UITypeEditor)),
DesignerSerializationVisibility(DesignerSerializationVisibility.Visible),
]
public String ValueMember
{
get
{
return this.valuemember;
}
set
{
this.valuemember = value;
}
}
}
EDIT:
I experimenting I just found out that that original DataGridViewComboBoxColumn can be made to behave exactly like I wanted to. By setting the DisplayStyle to Nothing the combobox control is only shown in edit mode.
