Serious Serialization problem

[Johnny J.]

I've made an inherited ListView control with a customized ColumnHeader Type.
I've overwritten the Columns property with a collection of my custom
ColumnHeader items. Now I would like to implement serialization so that
columns are persisted from designtime to runtime. But I cannot get it to
work.

I think it's because I don't know how to implement the type converter
correctly. Here's my suggestion for the type converter. Sample code for the
ListView, ColumnHeaderCol lection and ColumnHeaderIte m is supplied below. Can
anybody tell me what's wrong?

Cheers, Johnny J.

public class MyListViewColum nConverter : TypeConverter
{
public override bool CanConvertTo
(ITypeDescripto rContext context, Type destinationType )
{
if (destinationTyp e == typeof(Instance Descriptor))
{
return true;
}
return base.CanConvert To(context, destinationType );
}
public override object ConvertTo(IType DescriptorConte xt context, CultureInfo
culture, object value, Type destinationType )
{
if (destinationTyp e == typeof(Instance Descriptor) && value is
MyListViewColum n)
{
MyListViewColum nitem = (MyListViewColu mn)value;
ConstructorInfo ci = typeof(MyListVi ewColumn).GetCo nstructor(new Type[]
{ });
if (ci != null)
{
return new InstanceDescrip tor(ci, null, false);
}
}
return base.ConvertTo( context, culture, value, destinationType );
}
}

*************** *************** *************** *************
Listview, ColumnheaderCol lection, ColumnHeaderIte m code:
namespace MyListView
{
public class MyListView : ListView
{
private MyColumnHeaderC ollection myListViewColum nHeaders = null;
public MyListView()
{
myListViewColum nHeaders = new MyColumnHeaderC ollection(this) ;
//Other Code
}
public MyListView(ICon tainer container)
{
myListViewColum nHeaders = new MyColumnHeaderC ollection(this) ;
container.Add(t his);
//Other Code
}
[Localizable(tru e)]
[DesignerSeriali zationVisibilit y(DesignerSeria lizationVisibil ity.Content)]
[Editor("System. Windows.Forms.D esign.ColumnHea derCollectionEd itor,
System.Design, Version=2.0.0.0 , Culture=neutral ,
PublicKeyToken= b03f5f7f11d50a3 a", typeof(UITypeEd itor))]
[MergablePropert y(false)]
public new MyColumnHeaderC ollection Columns
{
get { return myListViewColum nHeaders; }
}
//Other Code
}
[DesignTimeVisib le(false)]
public class MyColumnHeaderC ollection : ListView.Column HeaderCollectio n
{
private SortedList columnList = new SortedList();
public new MyListViewColum n this[int index]
{
get
{ return (MyListViewColu mn)columnList.G etByIndex(index ); }
}
public override ColumnHeader Add(string str, int width, HorizontalAlign ment
textAlign)
{
MyListViewColum n column = new MyListViewColum n(str, width, textAlign);
this.Add(column );
return column;
}
public override int Add(ColumnHeade r column)
{
return this.Add(new MyListViewColum n(column));
}
public override void AddRange(Column Header[] values)
{
for (int index = 0; index < values.Length; index++)
{
this.Add(new MyListViewColum n(values[index]));
}
}
public int Add(MyListViewC olumn column)
{
int retValue = base.Add(column );
columnList.Add( column.ColumnID , column);
return retValue;
}
public new void Remove(ColumnHe ader column)
{
base.Remove(col umn);
columnList.Remo ve(((MyListView Column)column). ColumnID);
}
public new void RemoveAt(int index)
{
ColumnHeader column = this[index];
this.Remove(col umn);
}
public new void Clear()
{
base.Clear();
columnList.Clea r();
}
}
[DesignTimeVisib le(false)]
[TypeConverter(t ypeof(MyListVie wColumnConverte r))]
public class MyListViewColum n : ColumnHeader
{
private int m_ColumnID = 0;
private static int autoColumnID = 0;
public MyListViewColum n()
{
Initialize("", 60, HorizontalAlign ment.Left);
}
public MyListViewColum n(string str, int width, HorizontalAlign ment
textAlign)
{
Initialize(str, width, textAlign);
}
public MyListViewColum n(ColumnHeader column)
{
Initialize(colu mn.Text, column.Width, column.TextAlig n);
}
private void Initialize(stri ng str, int width, HorizontalAlign ment
textAlign)
{
base.Text = str;
base.Width = width;
base.TextAlign = textAlign;
m_ColumnID = autoColumnID++;
}
[Browsable(false )]
[DesignerSeriali zationVisibilit y(DesignerSeria lizationVisibil ity.Visible)]
public int ColumnID
{
get { return m_ColumnID; }
}
}
}

[Johnny J.]

I discovered I had missed a [Serializable] attribute on the MyListViewColum n
class. But that doesn't help - I get the error message:
MyListViewColum nConverter is unable to convert 'MyListView.MyL istViewColumn'
to 'System.Compone ntModel.Design. Serialization.I nstanceDescript or'.

/Johnny J.

"Johnny J." <jo**@altcom.se wrote in message
news:uS******** ******@TK2MSFTN GP03.phx.gbl...

I've made an inherited ListView control with a customized ColumnHeader
Type. I've overwritten the Columns property with a collection of my custom
ColumnHeader items. Now I would like to implement serialization so that
columns are persisted from designtime to runtime. But I cannot get it to
work.

I think it's because I don't know how to implement the type converter
correctly. Here's my suggestion for the type converter. Sample code for
the ListView, ColumnHeaderCol lection and ColumnHeaderIte m is supplied
below. Can anybody tell me what's wrong?

Cheers, Johnny J.

public class MyListViewColum nConverter : TypeConverter
{
public override bool CanConvertTo
(ITypeDescripto rContext context, Type destinationType )
{
if (destinationTyp e == typeof(Instance Descriptor))
{
return true;
}
return base.CanConvert To(context, destinationType );
}
public override object ConvertTo(IType DescriptorConte xt context,
CultureInfo culture, object value, Type destinationType )
{
if (destinationTyp e == typeof(Instance Descriptor) && value is
MyListViewColum n)
{
MyListViewColum nitem = (MyListViewColu mn)value;
ConstructorInfo ci = typeof(MyListVi ewColumn).GetCo nstructor(new Type[]
{ });
if (ci != null)
{
return new InstanceDescrip tor(ci, null, false);
}
}
return base.ConvertTo( context, culture, value, destinationType );
}
}

*************** *************** *************** *************
Listview, ColumnheaderCol lection, ColumnHeaderIte m code:
namespace MyListView
{
public class MyListView : ListView
{
private MyColumnHeaderC ollection myListViewColum nHeaders = null;
public MyListView()
{
myListViewColum nHeaders = new MyColumnHeaderC ollection(this) ;
//Other Code
}
public MyListView(ICon tainer container)
{
myListViewColum nHeaders = new MyColumnHeaderC ollection(this) ;
container.Add(t his);
//Other Code
}
[Localizable(tru e)]
[DesignerSeriali zationVisibilit y(DesignerSeria lizationVisibil ity.Content)]
[Editor("System. Windows.Forms.D esign.ColumnHea derCollectionEd itor,
System.Design, Version=2.0.0.0 , Culture=neutral ,
PublicKeyToken= b03f5f7f11d50a3 a", typeof(UITypeEd itor))]
[MergablePropert y(false)]
public new MyColumnHeaderC ollection Columns
{
get { return myListViewColum nHeaders; }
}
//Other Code
}
[DesignTimeVisib le(false)]
public class MyColumnHeaderC ollection : ListView.Column HeaderCollectio n
{
private SortedList columnList = new SortedList();
public new MyListViewColum n this[int index]
{
get
{ return (MyListViewColu mn)columnList.G etByIndex(index ); }
}
public override ColumnHeader Add(string str, int width,
HorizontalAlign ment textAlign)
{
MyListViewColum n column = new MyListViewColum n(str, width, textAlign);
this.Add(column );
return column;
}
public override int Add(ColumnHeade r column)
{
return this.Add(new MyListViewColum n(column));
}
public override void AddRange(Column Header[] values)
{
for (int index = 0; index < values.Length; index++)
{
this.Add(new MyListViewColum n(values[index]));
}
}
public int Add(MyListViewC olumn column)
{
int retValue = base.Add(column );
columnList.Add( column.ColumnID , column);
return retValue;
}
public new void Remove(ColumnHe ader column)
{
base.Remove(col umn);
columnList.Remo ve(((MyListView Column)column). ColumnID);
}
public new void RemoveAt(int index)
{
ColumnHeader column = this[index];
this.Remove(col umn);
}
public new void Clear()
{
base.Clear();
columnList.Clea r();
}
}
[DesignTimeVisib le(false)]
[TypeConverter(t ypeof(MyListVie wColumnConverte r))]
public class MyListViewColum n : ColumnHeader
{
private int m_ColumnID = 0;
private static int autoColumnID = 0;
public MyListViewColum n()
{
Initialize("", 60, HorizontalAlign ment.Left);
}
public MyListViewColum n(string str, int width, HorizontalAlign ment
textAlign)
{
Initialize(str, width, textAlign);
}
public MyListViewColum n(ColumnHeader column)
{
Initialize(colu mn.Text, column.Width, column.TextAlig n);
}
private void Initialize(stri ng str, int width, HorizontalAlign ment
textAlign)
{
base.Text = str;
base.Width = width;
base.TextAlign = textAlign;
m_ColumnID = autoColumnID++;
}
[Browsable(false )]
[DesignerSeriali zationVisibilit y(DesignerSeria lizationVisibil ity.Visible)]
public int ColumnID
{
get { return m_ColumnID; }
}
}
}