This is a migrated thread and some comments may be shown as answers.

Validating data with CellTemplates

13 Answers 391 Views

GridView

This is a migrated thread and some comments may be shown as answers.

This question is locked. New answers and comments are not allowed.

Mike Gorney asked on 11 Feb 2010, 04:52 PM

I have a GridView that is bound to a generic list. One of the properties is a bool value. After reading this thread:
http://www.telerik.com/community/forums/silverlight/gridview/row-validation-amp-row-details.aspx

am I correct in understanding that no validation events are fired when celltemplates are used?

I just need a editable checkbox for the column that fires the validation event, but if i do not assign a CellTemplate, the checkbox appears readonly in the column, even if i set IsReadOnly= False. Is there a way to get around this readonly behavior?

Also, i noticed in the docs: http://www.telerik.com/help/silverlight/gridview-columns-column-types.html#GridViewSelectColumn
there is a "GridViewCheckBox column" referred to, but am unable to find any other reference to it anywhere.

13 Answers, 1 is accepted

answered on 15 Feb 2010, 03:16 PM

281119-customcheckboxcolumnexample.zip

Hi Mike Gorney,

Generally when you use CellEditTemplate property you have to handle validation explicitly, since this will by-pass RadGridView's validation logic. RadGridView should validate some simple controls (used as CellEditTempate), by simple I mean a control which "value" property is bound directly to the property of the underlying business object. So according to that RadGridView will validate editors like CheckBox and TextBox. For more complex editors you have to create custom validation logic.

However if you need only a little bit more advanced checkbox column, you can take a look at the attached example. CustomCheckBoxColumn also handles "Space" key and supports all validation and editing functionalities of RadGridView. Let me know if this does not help.

Sincerely yours,
Nedyalko Nikolov
the Telerik team

Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking system and vote to affect the priority of the items.

answered on 16 Feb 2010, 04:26 PM

I have modified your example to look like the grid in my project and I am experiencing some odd behavior. In my solution, if I click the checkbox cell, the row is not selected, but in your solution (the one you attached above which i modified to look like mine) it works as expected. After going over all my settings and properties for the grid, the only difference I can see is that your solution uses version 2009.3.1412.1030, while I am using 2009.3.1314.1030 (this is the versions for the Telerik.Windows.Controls.GridView.dll).

Is this a known issue with the version i am using?

edit: I just replaced the dll you used, with the version 2009.3.1314.1030 I am using and the odd behavior does appear. Is there a work around with 2009.3.1314.1030 until 2009.3.1412.1030 is relased?

answered on 20 May 2010, 04:17 PM

I have updated to the latest Telerik files (2010.1.422.1030), and it seems that e.NewValue in the radGridView_CellValidating method always in your example returns false for the checkbox column. As well, i had previously created a custom column with a TextBox within a ScrollViewer that worked great. After I updated, i can click on the cell and it highlights as if its ready to be edited, but a cursor never appears, and typing does not alter the text within the TextBox. Can you perhaps show me what changes needed to be made for the latest files to work?

                    public class TextBoxColumn : GridViewBoundColumnBase         
                {         
                    public TextBoxColumn()         
                    {         
                        EditTriggers = GridViewEditTriggers.Default | GridViewEditTriggers.CellClick;         
                    }         
                     
                    private GridViewDataControl _ownderGrid;         
                     
                    public GridViewDataControl OwnerGrid         
                    {         
                        get         
                        {         
                            return _ownderGrid;         
                        }         
                     
                        set         
                        {         
                            if(_ownderGrid == value || value.IsNull())         
                                return;         
                     
                            _ownderGrid = value;         
                        }         
                    }         
                     
                    public override FrameworkElement CreateCellEditElement(GridViewCell cell, object dataItem)         
                    {         
                        ScrollViewer viewer = new ScrollViewer();         
                        TextBox textBox = new TextBox(){TextWrapping=TextWrapping.Wrap};         
                        ConfigureTextBox(textBox, DataMemberBinding.Path.Path, false);         
                        viewer.Content = textBox;         
                     
                        return viewer;         
                    }         
                     
                    private static void ConfigureTextBox(TextBox textBox, string path, bool isEditable)         
                    {         
                        textBox.IsTabStop = false;         
                        textBox.SetBinding(TextBox.TextProperty, CreateValueBinding(path, isEditable));         
                    }         
                     
                    private static Binding CreateValueBinding(string path, bool isEditable)         
                    {         
                        Binding valueBinding = new Binding         
                        {         
                            Path = new PropertyPath(path),         
                            Mode = isEditable ? BindingMode.TwoWay : BindingMode.OneWay,         
                            NotifyOnValidationError = true,         
                            ValidatesOnExceptions = true,         
                            UpdateSourceTrigger = UpdateSourceTrigger.Explicit         
                        };         
                        return valueBinding;         
                    }         
                }         

answered on 31 May 2010, 12:03 PM

281119-customcheckboxcolumnexample-new.zip

Hi Mike Gorney,

Generally when you create a custom column you should override some methods in order to cover all built-in functionality. For more information you can take a look at this blog post. You can find information about BindingTarget property useful.

I'm attaching a modified version of the example that demonstrates custom columns. Keep in mind that CustomCheckBox column is designed to enable editing of the underlying data object without cell to enter into edit mode (so no CellValidating and CellEditEnded events will occur). For the sake of the example I modified that column to enter into edit mode and then to edit the underlying value. Also in order to mimic built-in editing behavior you should set BindingTarget property accordingly. BindingTarget property could be used only when editor is a simple control. For the case with TextBoxColumn you should override GetNewValueFromEditor() method.

I hope this will help.

Regards,
Nedyalko Nikolov
the Telerik team

answered on 12 Aug 2010, 04:11 AM

Hi,

I'm having some major trouble with the RadGridView regarding editing and binding. My problem is that I've bound my GridView to a BO but the GridView has 3 editable columns in it. I used the CellEditingTemplate for these but they all have their own DataTemplate. Whenever I click into the cells to go into editing mode, I always get a Validation outline around the column, no matter what I do. I've caught all the validation events you can possibly catch and change the validation outcome on and set the e.Handled bool to true and no dice. The validation flyout message is blank and doesn't give any information. I can use reflection to see the error count is 4 but I cannot read the errors inside of it anyway. I had thought that when you used the CellEditingTemplate you bypassed the Telerik validation engine. Is there a way to turn this off? Do I have to derive my own column controls for every editable colum type? I would expect that I could do the following and not encounter so much trouble:

<telerik:RadGridView Name="grdDistCode" Grid.ColumnSpan="4" Grid.Column="1" Grid.Row="4" HorizontalAlignment="Left" Width="Auto" 
	             MinWidth="940" CanUserInsertRows="False" CanUserDeleteRows="False" CanUserSortColumns="False"
		     ShowGroupPanel="False" AutoGenerateColumns="False" IsTabStop="False" TabNavigation="Local" SelectionMode="Single"
		     FontFamily="Verdana" FontSize="14.667" CanUserFreezeColumns="False" AlternationCount="2" AlternateRowBackground="#FFD3DEBC" Background="#E6EED9"
	             RowIndicatorVisibility="Collapsed" ScrollViewer.HorizontalScrollBarVisibility="Auto" ScrollViewer.VerticalScrollBarVisibility="Auto" 
	             Loaded="grdDistCode_Loaded" SelectionChanged="grdDistCode_SelectionChanged">
		     <telerik:RadGridView.SortDescriptors>
			<telerikData:SortDescriptor Member="Sequence" SortDirection="Ascending"></telerikData:SortDescriptor>
		     </telerik:RadGridView.SortDescriptors>
		     <telerik:RadGridView.Columns>
			<telerik:GridViewDataColumn Header="Distribution Code" IsFilterable="False" IsReorderable="False" MinWidth="561">
                                <telerik:GridViewColumn.CellTemplate>
                                    <DataTemplate>
                                        <TextBlock Text="{Binding Code, Mode=TwoWay, NotifyOnValidationError=False, ValidatesOnDataErrors=False, ValidatesOnExceptions=False, ValidatesOnNotifyDataErrors=False}"></TextBlock>
                                    </DataTemplate>
                                </telerik:GridViewColumn.CellTemplate>
			        <telerik:GridViewColumn.CellEditTemplate>
				    <DataTemplate>
                                        <telerik:RadComboBox Name="rcbDistCodes" SelectedValuePath="ID" DisplayMemberPath="DistCodeAndDescription" Loaded="rcbDistCodes_Loaded"
							     SelectionChanged="rcbDistCodes_SelectionChanged" CanAutocompleteSelectItems="True" EmptyText="Select Dist. Code..."
						             SelectedValue="{Binding ID, Mode=TwoWay}"
							     ToolTipService.ToolTip="Select Distribution Code" LostFocus="tbxField_LostFocus"></telerik:RadComboBox>
                                    </DataTemplate>
				</telerik:GridViewColumn.CellEditTemplate>
                         </telerik:GridViewDataColumn>
			 <telerik:GridViewDataColumn DataMemberBinding="{Binding Percent, Mode=TwoWay, Converter={StaticResource percentConverter}}" Header="Percent" IsFilterable="False" IsReorderable="False" EditTriggers="CellClick" MinWidth="145">
			    <telerik:GridViewColumn.CellEditTemplate>
				<DataTemplate>
			            <telerik:RadMaskedTextBox Name="txtPercent" Value="{Binding Percent, Mode=TwoWay, UpdateSourceTrigger=Explicit}"
                                                              IsTabStop="True" TabIndex="1" MaskType="Numeric" Mask="p" SelectionOnFocus="SelectAll" LostFocus="tbxField_LostFocus"/>
				</DataTemplate>
		         </telerik:GridViewColumn.CellEditTemplate>
		  </telerik:GridViewDataColumn>
	          <telerik:GridViewDataColumn DataMemberBinding="{Binding Amount, Mode=TwoWay, Converter={StaticResource currencyConverter}}" Header="Amount/Number" IsFilterable="False" IsReorderable="False" EditTriggers="CellClick" MinWidth="145">
		    <telerik:GridViewColumn.CellEditTemplate>
			<DataTemplate>
			    <telerik:RadMaskedTextBox Name="txtAmount" Value="{Binding Amount, Mode=TwoWay, UpdateSourceTrigger=Explicit}" 
			                              MaskType="Numeric" Mask="c2" IsTabStop="True" TabIndex="1" SelectionOnFocus="SelectAll" LostFocus="tbxField_LostFocus"/>
                        </DataTemplate>
		    </telerik:GridViewColumn.CellEditTemplate>
		  </telerik:GridViewDataColumn>
		  <telerik:GridViewDataColumn UniqueName="Delete" Header="Delete" IsGroupable="False" IsFilterable="False" IsReorderable="False" EditTriggers="CellClick" MinWidth="85">
		    <telerik:GridViewDataColumn.CellTemplate>
			<DataTemplate>
			    <Button x:Name="btnDeleteDistCode" VerticalAlignment="Center" HorizontalAlignment="Center" Margin="3"  
				    Click="btnDeleteDistCode_Click" Tag="{Binding ID}" 
				    BorderBrush="Transparent" BorderThickness="0" Background="Transparent" ToolTipService.ToolTip="Delete">
					<Button.Content>
					    <Image Width="28" Height="28" Source="Assets/TrashCan.png"></Image>
					</Button.Content>
			    </Button>
			</DataTemplate>
	            </telerik:GridViewDataColumn.CellTemplate>
		    <telerik:GridViewDataColumn.CellEditTemplate>
			<DataTemplate>
			    <Button x:Name="btnDeleteDistCode" VerticalAlignment="Center" HorizontalAlignment="Center" Margin="3"  
				    Click="btnDeleteDistCode_Click" Tag="{Binding ID}" 
				    BorderBrush="Transparent" BorderThickness="0" Background="Transparent" ToolTipService.ToolTip="Delete">
			       <Button.Content>
			            <Image Width="28" Height="28" Source="Assets/TrashCan.png"></Image>
			       </Button.Content>
		            </Button>
		        </DataTemplate>
		    </telerik:GridViewDataColumn.CellEditTemplate>
		  </telerik:GridViewDataColumn>
                </telerik:RadGridView.Columns>                        
            </telerik:RadGridView>







Thanks in advance for your assistance.

answered on 13 Aug 2010, 08:06 AM

Hi Douglas,

About the validation problems I'll need some more info. I've seen that you are handling LostFocus events on every editor. Could you please send me also code behind? A sample solution which I can debug on my side will be great. And indeed you are right when you use CellEditTemplate you by-pass RadGridView's editing and validation logic.

Unfortunately with the current version of RadGridView a whole row cannot enter into edit mode. This task is already in our TODO list, but I cannot commit with any date or release when this feature will be ready.

Best wishes,
Nedyalko Nikolov
the Telerik team

answered on 16 Oct 2012, 08:38 AM

Hey,
I'm trying to make validation on datepicker in radgridview control.
my code looks like this:

<telerik:GridViewDataColumn Header="Start Date" Background="#FFEA5555">

<telerik:GridViewDataColumn.CellTemplate>

<DataTemplate>

<DatePicker x:Name="dp_costing"

Style="{StaticResource ConstructionDatePickerStyle}">

<DatePicker.SelectedDate>

<Binding Path="SubContract.StartDate" Mode="TwoWay" UpdateSourceTrigger="PropertyChanged"

ValidatesOnDataErrors="True" NotifyOnValidationError="True" ValidatesOnExceptions="True">

</Binding>

</DatePicker.SelectedDate>

<i:Interaction.Behaviors>

<b:ValidationErrorBehavior Command="{Binding OnErrorOccuredCmd}"/>

</i:Interaction.Behaviors>

</DatePicker>

</DataTemplate>

</telerik:GridViewDataColumn.CellTemplate>

<telerik:GridViewColumn.CellEditTemplate>