Programming Grouping

[Lan Mo]

I want to group a column by code and make it not
visible in the coulmns when a column is added to group, re-visible when user drag it back.

To add it to group, I use code:
GGC1.TableDescriptor.GroupedColumns.Clear();
GGC1.TableDescriptor.GroupedColumns.Add("year");

To hide it,
GGC1.TableDescriptor.VisibleColumns.Remov("year");
To re-visible it,
GGC1.TableDescriptor.VisibleColumns.Add("year");

But I don''t know in which enents I should put hide/re-show codes in. and How can I dynamiclly know the column name instead of hard-coded "year" when user drag/drop a column in the "grouping drop area"
Thanks,

Lan

[Administrator]

To hide the grouped column, you can subcribe to the grid.TableDescriptor.GroupedColumns.Changing event to show and hide the column in your event handler.

private void GroupedColumns_Changing(object sender, Syncfusion.Collections.ListPropertyChangedEventArgs e)
{
	SortColumnDescriptor scd = e.Item as SortColumnDescriptor;
	if(e.Action == Syncfusion.Collections.ListPropertyChangedType.Remove)
			this.gridGroupingControl1.TableDescriptor.VisibleColumns.Add(scd.Name);
	else if(e.Action == Syncfusion.Collections.ListPropertyChangedType.Add)
	this.gridGroupingControl1.TableDescriptor.VisibleColumns.Remove(scd.Name);
}

[Lan Mo]

I can''t find the event grid.TableDescriptor.GroupedColumns.Changing in Grid property window (event tab)

lan

>To hide the grouped column, you can subcribe to the grid.TableDescriptor.GroupedColumns.Changing event to show and hide the column in your event handler.
>
>

>private void GroupedColumns_Changing(object sender, Syncfusion.Collections.ListPropertyChangedEventArgs e)
>{
>	SortColumnDescriptor scd = e.Item as SortColumnDescriptor;
>	if(e.Action == Syncfusion.Collections.ListPropertyChangedType.Remove)
>			this.gridGroupingControl1.TableDescriptor.VisibleColumns.Add(scd.Name);
>	else if(e.Action == Syncfusion.Collections.ListPropertyChangedType.Add)
>	this.gridGroupingControl1.TableDescriptor.VisibleColumns.Remove(scd.Name);
>}
>

>

[Lan Mo]

I added the event, but it never fired when add/remove groups
this.gridGroupingControl1.TableDescriptor.GroupedColumns.Changing+=new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);
Why?

Lan

>To hide the grouped column, you can subcribe to the grid.TableDescriptor.GroupedColumns.Changing event to show and hide the column in your event handler.
>
>

>private void GroupedColumns_Changing(object sender, Syncfusion.Collections.ListPropertyChangedEventArgs e)
>{
>	SortColumnDescriptor scd = e.Item as SortColumnDescriptor;
>	if(e.Action == Syncfusion.Collections.ListPropertyChangedType.Remove)
>			this.gridGroupingControl1.TableDescriptor.VisibleColumns.Add(scd.Name);
>	else if(e.Action == Syncfusion.Collections.ListPropertyChangedType.Add)
>	this.gridGroupingControl1.TableDescriptor.VisibleColumns.Remove(scd.Name);
>}
>

>

[Administrator]

Here is a little sample that worked for me using 3.2.1.0.

http://www.syncfusion.com/Support/user/uploads/GGC_HideGroups_4beaa152.zip

[Lan Mo]

I got your sample. It works well.
I also create a new form, add code like your sample, it works well also.

But I add the same code to my real form, the
event is never fired. I can''t figure out what settings could prevent the event.

My GGC form is a generic form to edit any kind table data.

Lan

>Here is a little sample that worked for me using 3.2.1.0.
>
>http://www.syncfusion.com/Support/user/uploads/GGC_HideGroups_4beaa152.zip
>
>

[Administrator]

Check and make sure the code where you subscribe to this event in your project is hit.

Are you using nested tables in your application? The sample only used a flat table and grouped it. If you are trying to do this for nested tables, then you would have to subscribe to the event for each one of nested tables.

If you can upload a sample showing the problem, we can try to track it down.

[Lan Mo]

I upload my form''s file. I''am afraid you can''t run it because it has to use our definition database tables. lan >Check and make sure the code where you subscribe to this event in your project is hit. > >Are you using nested tables in your application? The sample only used a flat table and grouped it. If you are trying to do this for nested tables, then you would have to subscribe to the event for each one of nested tables. > >If you can upload a sample showing the problem, we can try to track it down. frmGrid_9606.zip frmGrid_7291.zip

[Administrator]

Try subscribing to the event after you set the datasource:

gdBase.DataSource = mGridDataSet.Tables[table];
this.gdBase.TableDescriptor.GroupedColumns.Changing += new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);

You will also have to find a good spot to unsubscribe to it as you do not want multiple handlers hooked.

[Lan Mo]

You are great!!! I did as you said, It works.
whenever I re-load data, I unbound datasource and unsubscribe the event by
//unbound grid
gdBase.DataSource=null;
//unsubscribe the event this.gdBase.TableDescriptor.GroupedColumns.Changing -= new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);

After loaded table data, I bound datasource and subscribe the event
// bound to grid
gdBase.DataSource = mGridDataSet.Tables[table];
//subscribe the event this.gdBase.TableDescriptor.GroupedColumns.Changing += new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);

Thanks for great support!

Lan

Here is copy of new LoadData() code:
private void LoadData(string table,string field,string Where,int SubsetID)
{

try
{
//unbound grid
gdBase.DataSource=null;
//unsubscribe the event
this.gdBase.TableDescriptor.GroupedColumns.Changing -= new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);

gdBase.TableDescriptor.Columns.Clear();
gdBase.ResetTableDescriptor();
// this avoid "No current record error" when lasr record is not existing in the new gris
gdBase.Table.ResetCurrentRecord();
gdBase.Table.ResetCurrencyManager();

// retrieve data
// if (table.ToUpper()=="SECT_ATTRIBUTE") // for attribute grid tree
// mSingleTableObj=new BL.singleTable(table,null,Where,SubsetID);
// else
// mSingleTableObj=new BL.singleTable(table,field,Where,SubsetID);

mSingleTableObj=new BL.singleTable(table,field,Where,SubsetID);

mGridDataSet = mSingleTableObj.LoadDataSet();
// bound to grid
//DataTable tb=mGridDataSet.Tables[table];
gdBase.DataSource = mGridDataSet.Tables[table];
//subscribe the event
this.gdBase.TableDescriptor.GroupedColumns.Changing += new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);

gdBase.TableDescriptor.Columns.LoadDefault();

// load table field definitions
dsFields=BL.Access.LoadDataSet("dict_field",null,"table_name=''" +table +"''");

// set to the first record so it will be highlighted
//gdBase.Table.CurrentRecord = gdBase.Table.Records[0];
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
}

>Try subscribing to the event after you set the datasource:
>

>gdBase.DataSource = mGridDataSet.Tables[table];
>this.gdBase.TableDescriptor.GroupedColumns.Changing += new Syncfusion.Collections.ListPropertyChangedEventHandler(GroupedColumns_Changing);
>

>
>You will also have to find a good spot to unsubscribe to it as you do not want multiple handlers hooked.