Combobox with Image and Text

[Peter Bogoyavlensky]

Would it be possible to create combobox (within GridViewComboBoxColumn) with image and text (as it was done for RadDropDownList)?

[Dess | Tech Support Engineer, Principal]

Hello Peter,

Thank you for writing.

In order to display an image inside the RadDropDownListEditor, you can subscribe to the RadDropDownListEditorElement.VisualItemFormatting event and set the VisualItem.Image property to the desired image:

private void Form1_Load(object sender, EventArgs e)
{
    this.categoriesTableAdapter.Fill(this.nwindDataSet.Categories);

    GridViewComboBoxColumn comboColumn = new GridViewComboBoxColumn("Combo column");
    comboColumn.DataSource = this.categoriesBindingSource;
    comboColumn.ValueMember = "CategoryID";
    comboColumn.DisplayMember = "CategoryName";
    this.radGridView1.Columns.Add(comboColumn);

    this.radGridView1.CellEditorInitialized += radGridView1_CellEditorInitialized;
    this.radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
}

private void radGridView1_CellEditorInitialized(object sender, GridViewCellEventArgs e)
{
    RadDropDownListEditor ddl = e.ActiveEditor as RadDropDownListEditor;
    if (ddl != null)
    {
        RadDropDownListEditorElement editorElement = ddl.EditorElement as RadDropDownListEditorElement;
        editorElement.VisualItemFormatting -= editorElement_VisualItemFormatting;
        editorElement.VisualItemFormatting += editorElement_VisualItemFormatting;
    }
}

private void editorElement_VisualItemFormatting(object sender, VisualItemFormattingEventArgs args)
{
    DataRowView rowView = args.VisualItem.Data.DataBoundItem as DataRowView;
    if (rowView != null)
    {
        args.VisualItem.Image =ImageHelper.GetImageFromBytes(rowView.Row["Picture"] as byte[]);
        args.VisualItem.ImageLayout = ImageLayout.Zoom;
    }
}

I hope this information helps. Should you have further questions, I would be glad to help.
 
Regards,
Desislava
Telerik

 

 

[Emanuele]

Please, can you explain me where did you set the images for each element of the comboBox?

I tried to do this but when I leave the cell it shows me only the text and not the image:

 private void gridView_layers_CellEditorInitialized(object sender, GridViewCellEventArgs e)
 {
     RadDropDownListEditor editor = e.ActiveEditor as RadDropDownListEditor;
     if (editor != null)
     {
         RadDropDownListEditorElement editorElement = editor.EditorElement as RadDropDownListEditorElement;

         RadListDataItem test= new RadListDataItem();
         tratteggio.Image = Resources.addlayer;
         tratteggio.Text = "test";

         RadListDataItem test2= new RadListDataItem();
         continuo.Image = Resources.dellayer;
         continuo.Text = "test2";

         RadDropDownListEditorElement element = editor.EditorElement as RadDropDownListEditorElement;
         element.DropDownStyle = RadDropDownStyle.DropDownList;
         element.ShowImageInEditorArea = true;
         element.EditableElement.TextImageRelation = TextImageRelation.ImageBeforeText;
         element.EditableElement.ImageAlignment = ContentAlignment.MiddleRight;
         element.Items.Add(test);
         element.Items.Add(test2);
         
         editorElement.VisualItemFormatting -= editorElement_VisualItemFormatting;
         editorElement.VisualItemFormatting += editorElement_VisualItemFormatting;
     }

 }

[Nadya | Tech Support Engineer]

Hello, Emanuele,

If I have correctly understood your approach, you want to see the image in the cell when you leave the cell. In this case, what I can suggest is to try setting the Image property of the EditableElement. You can show an image in the editing area of the RadDropDownListEditorElement by setting the ShowImageInEditorArea property as you have already found out. Then you can change the Image property of the EditableElement based on the selected item by handling the SelectedIndexChanged event. 

Please refer to the attached project.

I hope this helps. Should you have any other questions do not hesitate to ask. 

Regards,
Nadya | Tech Support Engineer
Progress Telerik