Sony Arouje

My current project requires several silverlight user controls. Most of the control has some common functionalities. I decided to create a base class inherits from UserControl. Then add the base class to my user controls.

The issue arise when I tried to build the solution, I started getting the bellow compile time error.

Error    1    Partial declarations of ‘ImageEditor.Controls.CallOut’ must not specify different base classes    F:\XXXX\obj\Debug\Controls\CallOut.g.i.cs    36    26    <ProjectName>

The solution to this issue is, in XAML change <UserControl …..</UserControl> to the name of your base class. See the eg. below

<UI:ControlBase x:Class="ImageEditor.Controls.CallOut"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:UI="clr-namespace:ImageEditor.Controls"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400">    
    <Grid x:Name="LayoutRoot" Background="White">
        <Border  x:Name="rectBorder" Grid.Row="0" BorderBrush="Black" BorderThickness="3" CornerRadius="5">
            <TextBox x:Name="txtAnnotate" AcceptsReturn="True"></TextBox>
        </Border>
    </Grid>
</UI:ControlBase >

In the above xaml I replace UserControl with my base class. In order to use my base class I should refer my namespace using xmlns:UI=”clr-…..”. You can see the changes by looking at the sections underlined.