New Post: Binding combobox content of a property in propertygrid

I need to have a customized editor definition of a property in the Property Grid.
The property definition contains a combo box and a button. Combo box items have to be populated as a list of image files present in a specified folder within the project. The button is used to open a file browser and browse for image files and copy the selected files in the same folder alongwith adding it to the combo box content.

I have written the property definition data template as below. But neither i am unable to bind the list to the combo box from xaml code nor i am getting the instance of the combo box in C# code end so that i can bind it there.

<xctk:EditorDefinition >

<xctk:EditorDefinition.PropertiesDefinitions>
                                    <xctk:PropertyDefinition Name="Image" />
                                </xctk:EditorDefinition.PropertiesDefinitions>
                            <xctk:EditorDefinition.EditorTemplate>
                                <DataTemplate>
                                    <Grid>
                                        <Grid.ColumnDefinitions>
                                            <ColumnDefinition Width="5*"/>
                                            <ColumnDefinition Width="*"/>
                                        </Grid.ColumnDefinitions>
                                        <ComboBox Grid.Column="0" x:Name="ImageCombo" SelectionChanged="Image_OnSelectionChanged" ItemsSource="{Binding CustomKeyImageList}" Initialized="ImageCombo_OnInitialized">
                                          </ComboBox>
                                        <Button Grid.Column="1" Content="..." Click="OnAddCustomKeyImagesButtonClick"></Button>
                                    </Grid>
                                </DataTemplate>
                            </xctk:EditorDefinition.EditorTemplate>
                        </xctk:EditorDefinition>

Please come up with a solution.

Thanks in advance