Customizing Columns in Datagrid – Adding Image and Radio Button to windows Datagrid

• CustomizedDataGrid - 37.8 Kb

Introduction

Customizing Columns in Datagrid – Adding Image and Radio Button to windows Datagrid

Many of us have always used datagrid in our web and windows applications. In web we can easily display checkbox, radio buttons, image button etc by using template columns. Adding radio button or image button in windows data grid is not that easy as it’s in web. We can’t directly drag and drop a radio button inside a windows datagrid; instead we require our custom radio button or better said a CustomDatagridColumn style for radio button. This is what I will try to show in this article. I will try to explain most part of code so as to make you understand how this stuff works. Also we will use typed dataset in this example.

I would recommend you to download zipped code file and have a short look at code.

 Lets 1st start looking at file RadioButtonColumnStyle.cs, here we have overridden two functions – Paint and SetDataGridInColumn

protected override void Paint(Graphics g,Rectangle Bounds,CurrencyManager Source,int RowNum, Brush BackBrush ,Brush ForeBrush ,bool AlignToRight) 
  {
   try
   {
    base.Paint(g,Bounds,Source,RowNum,BackBrush,ForeBrush,AlignToRight);
    object o = GetColumnValueAtRow(Source, RowNum);
    string textval ;
    if(o==null || o==DBNull.Value)
     textval = this.NullText;
    else
     textval = o.ToString();
    if (textval == "Y")
     System.Windows.Forms.ControlPaint.DrawRadioButton(g,Bounds.X,Bounds.Y,20,16,System.Windows.Forms.ButtonState.Checked);
    else
     System.Windows.Forms.ControlPaint.DrawRadioButton(g,Bounds.X,Bounds.Y,20,16,System.Windows.Forms.ButtonState.Normal);
   }
   catch(Exception ex)
   {
    //MessageBox.Show(ex.Message);
   }
  }

Here we see that we are calling a function called GetColumnValueAtRow. This function gets the value of the cell/column in particular row as specified. Now in our case if the value we got is “Y”, we draw a radiobutton using DrawRadioButton in checked state else we draw it in Normal state.

In other override function SetDataGridInColumn, We declare mouse event handler for those datagrids which uses radiobuttonColumnstyle.

private void DataGrid_MouseDown(object sender, MouseEventArgs e)
  {
   DataGrid.HitTestInfo hti = this.DataGridTableStyle.DataGrid.HitTest( e.X, e.Y );
   if(hti.Column != this.ColumnNumber)
    return;
   if ( e.Button == MouseButtons.Left &&
    hti.Type == DataGrid.HitTestType.Cell )
   {
    Click( new RadioButtonColumnEventArgs( hti.Row, hti.Column));

   }
  }

The Above code shows the event handler for MouseDown, in this we 1st gets the area hit by mouse using HitTest function. After that we call click function passing the required arguments. This event is implemented in form1.cs file.

Now let’s see FillDataGrid function in form1.cs file code.

private void FillDataGrid()
  {
   DataSet DataSetMain = new DataSet();
   DataSetMain = GetDataSet();
   datasetCategories1.Merge(DataSetMain);
   RadioButtonColumnStyle RadioColumnStyleObject = null;
   FlatLabelColumnStyle FlatColumnStyleObject = null;
   ButtonColumnStyle ButtonColumnStyleObject=null;
   try
   {
    DataGridTableStyle GridTableStyle = new DataGridTableStyle();    
    GridTableStyle.MappingName="Table";
    GridTableStyle.BackColor = Color.FromArgb(220,229,234);
    GridTableStyle.HeaderForeColor = Color.Navy;
    GridTableStyle.AllowSorting=false;
    GridTableStyle.HeaderFont = new Font("Microsoft Sans Serif", 8.25F, ((System.Drawing.FontStyle)((System.Drawing.FontStyle.Bold))), System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
    GridTableStyle.HeaderBackColor=Color.FromArgb(220, 229, 234);
    GridTableStyle.HeaderForeColor=Color.Black;
    GridTableStyle.GridLineStyle = DataGridLineStyle.None;
    if(datasetCategories1.Tables.Count>0)
    {     
     GridTableStyle.GridColumnStyles.Clear();
     GridTableStyle.RowHeadersVisible=false;
     for(int i=0;i <datasetCategories1.Tables["Table"].Columns.Count; ++i)
     {
      if(datasetCategories1.Tables["Table"].Columns[i].ColumnName=="DeleteButton")
      {
       Bitmap BitmapObjectDelete = new Bitmap(path + "file://Images//deleteIcon.GIF");
       Bitmap BitmapObjectPressed = new Bitmap(path + "file://Images//deleteIcon.GIF");
       ButtonColumnStyleObject = new ButtonColumnStyle(i,BitmapObjectDelete,BitmapObjectPressed);
       ButtonColumnStyleObject.HeaderText =  "";
       ButtonColumnStyleObject.MappingName =  "DeleteButton";
       ButtonColumnStyleObject.CellButtonClicked -= new ButtonColumnEventHandler(ButtonColumnStyleObject_Click);
       ButtonColumnStyleObject.CellButtonClicked += new ButtonColumnEventHandler(ButtonColumnStyleObject_Click);
       dataGrid1.MouseDown += new MouseEventHandler(ButtonColumnStyleObject.HandleMouseDown);
       dataGrid1.MouseUp += new MouseEventHandler(ButtonColumnStyleObject.HandleMouseUp);
       dataGrid1.MouseMove += new MouseEventHandler(ButtonColumnStyleObject.HandleMouseMove);
       GridTableStyle.GridColumnStyles.Add(ButtonColumnStyleObject);
      }
      else if(datasetCategories1.Tables["Table"].Columns[i].ColumnName=="RadioButton")
      {
       /*for Radio Button */
       RadioColumnStyleObject = new RadioButtonColumnStyle();
       RadioColumnStyleObject.HeaderText = "";
       RadioColumnStyleObject.MappingName =  "RadioButton";
       RadioColumnStyleObject.Alignment = HorizontalAlignment.Center;           
       RadioColumnStyleObject.ReadOnly = false;
       RadioColumnStyleObject.Width = 30;
       RadioColumnStyleObject.ColumnNumber= 1 ;
       RadioColumnStyleObject.Click += new RadioButtonColumnStyle.RadioButtonColumnClickHandler(RadioColumnStyle_Click);
       GridTableStyle.GridColumnStyles.Add(RadioColumnStyleObject); 
      }
      else
      {         
      
       if(datasetCategories1.Tables["Table"].Columns[i].ColumnName=="CategoryName" || datasetCategories1.Tables["Table"].Columns[i].ColumnName=="Description" )
       {
        FlatColumnStyleObject = new FlatLabelColumnStyle();
        switch (datasetCategories1.Tables["Table"].Columns[i].ColumnName)
        {  
         case "CategoryName":
          FlatColumnStyleObject.HeaderText ="CategoryName";
          FlatColumnStyleObject.Width = 100;
          break;
         case "Description":
          FlatColumnStyleObject.HeaderText ="Description";
          FlatColumnStyleObject.Width = 220;
          break;
        }
        FlatColumnStyleObject.MappingName = datasetCategories1.Tables["Table"].Columns[i].ColumnName;
        FlatColumnStyleObject.linecolor=Color.Brown;
        FlatColumnStyleObject.showline = true;
        GridTableStyle.GridColumnStyles.Add(FlatColumnStyleObject);
       }
      }
     }
    }
    dataViewCategories = datasetCategories1.Tables["Table"].DefaultView;
    dataGrid1.DataSource= dataViewCategories;
    dataGrid1.TableStyles.Clear();
    GridTableStyle.PreferredRowHeight = 25;
    dataGrid1.TableStyles.Add(GridTableStyle); 
   }
   catch(Exception ex)
   {
    MessageBox.Show(ex.ToString());
   }

  }

In this function we create our custom GridTableStyle and add it to our datagrid. Also we have binding of datagrid1 to dataviewCategories which has binding to datasetCategories. We created an event handler for Click event of RadioButtonColumnClickHandler delegate. Below is the code for it.

private void RadioColumnStyle_Click(RadioButtonColumnEventArgs e)
  {
   dataViewCategories.AllowEdit = true;
   try
   {
    dataViewCategories.RowFilter = "RadioButton='Y'";
    if(dataViewCategories.Count == 1)
    {
     this.BindingContext[dataViewCategories].Position = 0;
     DataRowView drv1 = (DataRowView)this.BindingContext[dataViewCategories].Current;
     drv1["RadioButton"] = "N";
     this.BindingContext[dataViewCategories].EndCurrentEdit();
    }
    dataViewCategories.RowFilter = "";
    this.BindingContext[dataViewCategories].Position = e.RowIndex;
    DataRowView drv = (DataRowView)this.BindingContext[dataViewCategories].Current;
    drv["RadioButton"] = "Y";
    this.BindingContext[dataViewCategories].EndCurrentEdit();
    CatName.Text = drv["CategoryName"].ToString();
    Description.Text = drv["Description"].ToString();
   }
   catch(Exception ex)
   {
    MessageBox.Show(ex.Message);
   }
  }

In this we first check if there is any radio button already selected, if so we deselect it by editing that row and then we get the clicked row index by using e.RowIndex and assign it to the dataViewCategories current position. Then we select that row by editing it and also assign the corresponding textboxes with required values.

Similarly we have implemented FlatLabelColumnStyle and ButtonColumnStyle. Both are quite simple to understand and have been properly implemented in code. If any one of you have queries on any part of it please let me know.